Detailed Description
The present invention provides methods for reducing the environmental effectiveness of environmental pollutants. The term "reducing environmental effectiveness" as used throughout this document refers to stabilizing, immobilizing (immobilizing), immobilizing (fixing), packaging, separating, restraining (containing), destroying, detoxifying, decomposing, and decomposing at least one environmental contaminant, reducing the amount of at least one environmental contaminant, reducing the mobility of at least one environmental contaminant, and/or reducing the migration ability of at least one environmental contaminant. Stabilization and/or immobilization may be performed in a medium. Reducing the environmental effectiveness of environmental pollutants in turn reduces the biological effectiveness of the pollutants and thus their bioaccumulation.
The terms "an environmental contaminant (environmental pollutant) and environmental contaminants (environmental pollutants)" as used herein mean chemical elements or compounds or mixtures thereof known to be harmful to humans and/or to affect the environment (ecosystem). Environmental pollutants are often regulated by one or more government agencies. Examples of environmental pollutants include various forms of mercury, such as elemental mercury (metallic mercury), organic mercury compounds, and inorganic mercury compounds, other organic species (including, for example and without limitation, hydrophobic organic compounds, polycyclic aromatic hydrocarbons, polyfluoroalkyl species, perfluoroalkyl species, polychlorinated biphenyls, dioxins, furans, and/or chlorinated pesticides), hazardous elements, organic heavy element compounds, and inorganic heavy element compounds (including, for example and without limitation, compounds containing As, pb, zn, cu, cr, ni and/or Cd), and other environmental pollutants known to those of skill in the art.
As used throughout this document, terms such as "treated," "contacted," and "reconditioned" indicate that the halogen-containing sorbent interacts with a substance containing one or more environmental pollutants in a manner that reduces the environmental effectiveness of the one or more environmental pollutants.
The remediation agents in the practice of the present invention are halogen-containing sorbents and oxidants. Halogen-containing sorbents are sometimes referred to herein as "halogenated sorbents". The halogen-containing sorbent is typically formed from one or more halogen-containing compounds and one or more matrix materials. Many matrix materials, especially activated carbon, can be used or obtained in a wide variety of particle sizes from nanometers to centimeters.
The matrix material includes carbonaceous materials and inorganic materials. Suitable carbonaceous materials that may be used as adsorbents in the practice of the invention include, for example, but are not limited to, activated carbon, carbon black, charcoal, and coke. The preferred carbonaceous material is activated carbon, which can be used in a number of forms including, for example, but not limited to, powdered, granular, microspheroidal, pellet or extruded forms, and high specific surface area.
Suitable inorganic materials include inorganic oxides such as alumina (amorphous alumina and crystalline alumina), silica, magnesia, and titania; natural zeolites such as chabazite, clinoptilolite and faujasite; synthetic zeolites such as synthetic chabazite, zeolites with a high Si to Al ratio (such as ZSM-5, beta zeolite), zeolites with a medium Si to Al ratio (such as Y-type zeolite, mordenite), zeolites with a low Si to Al ratio (such as A-type zeolite, X-type zeolite), silicoaluminophosphate (SAPO) zeolites, ion exchanged zeolites, uncalcined zeolites with or without organic structure directing agents, aluminosilicates with ordered pore structures (such as MCM-41, MCM-48, SBA-15, HMS, MSU-X), clay minerals such as kaolin, kaolinite, bentonite and montmorillonite, synthetic clays such as laponite, magnesium bentonite, zinc montmorillonite, stevensite, kaolinite and hectorite, organoclays such as stearoyl trimethylammonium salt, dimethyl dialkyl (C14-C18) ammonium salt, methyldihydroxyethyl ammonium salt and hydrogenated tallow ammonium salt and aminopropyl triethoxysilane and quaternary ammonium salt, bentonite, hectorite and attapulgite treated with ammonium salt, and N, N, N, hexadecyl-triethoxysilane, montmorillonite, hectorite treated with an inorganic hydroxide catalyst such as hydrotalcite, a mixture of metal oxide, a metal oxide catalyst such as diatomaceous earth oxide, a mixture of layers comprising diatomaceous earth, and a metal oxide catalyst such as diatomaceous earth oxide Silica and/or titania, inorganic carbonates such as alkali metal carbonates (e.g., sodium carbonate and potassium carbonate) and alkaline earth metal carbonates (e.g., calcium carbonate), and mixtures of any two or more of the foregoing. Preferred inorganic materials include inorganic oxides (especially silica), natural zeolites (especially chabazite) and clay minerals (especially kaolinite and bentonite), caCO3 also being a preferred matrix material.
The halogen element in the halogen-containing sorbent may be chlorine, bromine, iodine, or a mixture of any two or more of these halogens. Bromine and iodine are preferred halogens, and bromine is a more preferred halogen. Suitable halogen-containing species for forming the halogen-containing sorbent include, for example, but are not limited to, elemental iodine and/or iodine compounds, elemental bromine and/or bromine compounds, elemental chlorine and/or chlorine compounds, and other suitable halogen compounds, as known to those skilled in the art. Halogen-containing species that may be used include elemental halogens, halogen acids, alkali metal halides, alkaline earth metal halides, and ammonium halides. Mixtures of any two or more halogen-containing materials may be used, and the mixtures may contain the same or different halogens.
Hydrohalic acids include hydrogen chloride, hydrogen bromide and hydrogen iodide. Bromide and iodide are preferred halides, with bromide being more preferred. Alkali metal halides include lithium halide, sodium halide, potassium halide, rubidium halide and cesium halide, with sodium halide and potassium halide being preferred. Preferred alkali metal halides include sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide and potassium iodide, with sodium bromide, potassium bromide and potassium iodide being more preferred. Alkaline earth metal halides include magnesium halides, calcium halides, strontium halides, and barium halides, with magnesium halides and calcium halides being preferred. Preferred alkaline earth metal halides include magnesium chloride, magnesium bromide, magnesium iodide, calcium chloride, calcium bromide and calcium iodide, with magnesium bromide and calcium bromide being more preferred. Ammonium halides include ammonium chloride, ammonium bromide and ammonium iodide, with the preferred ammonium halide being ammonium bromide. More preferred halogen-containing species include elemental bromine, hydrogen bromide, sodium bromide, potassium bromide, and calcium bromide, especially sodium bromide.
Halogen-containing sorbents can be made from matrix materials and one or more halogen-containing substances as described in U.S. Pat. nos. 6,953,494 and 9,101,907 and international patent publication No. WO 2012/071206, especially for bromine-containing sorbents. In some embodiments, the preferred halogen-containing sorbent is a bromine-containing sorbent. In some embodiments, the preferred halogen-containing sorbent is a halogen-containing activated carbon. In other embodiments, preferred halogen-containing activated carbons are chlorine-containing activated carbons, bromine-containing activated carbons, and iodine-containing activated carbons. In a preferred embodiment, the halogen-containing sorbent is an iodine-containing activated carbon and a bromine-containing activated carbon. In a more preferred embodiment, the halogen-containing sorbent is a bromine-containing activated carbon. Bromine-containing activated carbon is commercially available from Albemarle Corporation.
In other embodiments, preferred halogen-containing sorbents are chlorine-containing activated carbon and iodine-containing activated carbon. In still other embodiments, the preferred halogen-containing sorbents are halogen-containing chabazite, halogen-containing bentonite, halogen-containing kaolinite, and halogen-containing silica, and the more preferred halogen-containing sorbents are iodine-containing chabazite, bromine-containing chabazite, iodine-containing bentonite, bromine-containing bentonite, iodine-containing kaolinite, bromine-containing kaolinite, iodine-containing silica, and bromine-containing silica, and the still more preferred are bromine-containing silica, bromine-containing kaolinite, and bromine-containing bentonite.
In another embodiment, preferred halogen-containing sorbents include bromine-containing silica, bromine-containing kaolinite and bromine-containing bentonite.
The amount of halogen (or halogen content) on the matrix material generally corresponds to a total bromine content (or calculated as bromine) in the range of about 0.1 wt.% to about 50 wt.%, preferably in the range of about 0.25 wt.% to about 40 wt.%, more preferably in the range of about 0.5 wt.% to about 35 wt.%, even more preferably in the range of about 1 wt.% to about 20 wt.%, and still more preferably in the range of about 2 wt.% to about 12 wt.%, based on the total weight of the halogen-containing sorbent.
Unless otherwise indicated, the phrases "calculated as bromine", "reported as bromine", "calculated as bromine", and similar phrases for halogen as used throughout this document refer to the amount of halogen, wherein the values are calculated for bromine. For example, chlorine may be used, but the amount of halogen in the halogen-containing sorbent is expressed in terms of the value for bromine.
Halogen-containing activated carbons suitable for use in the methods of the present invention may have a wide range of particle sizes and distributions from nanometers to centimeters, and may be formed from activated carbon forms including, for example, but not limited to, powdered, granular, microspheroidal, pellet or extruded forms, high specific surface area, a variety of unique pore structures, and other features familiar to those skilled in the art.
Halogen-containing sorbents, particularly halogen-containing carbonaceous sorbents, particularly iodine-containing sorbents and bromine-containing sorbents, more particularly bromine-containing carbonaceous sorbents, can reduce the environmental effectiveness of contaminants in materials by means including, for example and without limitation, oxidation and/or adsorption. Adsorption can reduce the environmental effectiveness of environmental pollutants by reducing the mobility of such pollutants. Other ways in which halogen-containing sorbents can reduce the environmental effectiveness of contaminants are by enhancing the degradation of such contaminants via surface reactions, and/or by inhibiting the formation of contaminants (e.g., methylmercury), and/or by other mechanisms. In the process of the present invention, whether applied to a solid or a liquid or a combination thereof, the environmental contaminants adsorbed by the halogen-containing adsorbent are stabilized such that the amount of desorption into the environment is substantially minimized.
Oxidizing agents suitable for use in the practice of the present invention are compounds capable of oxidizing elemental mercury. These oxidizing agents are generally capable of oxidizing other heavy elements including chromium, arsenic, and selenium. In the practice of the present invention, these oxidizing agents are inorganic oxidizing agents and organic oxidizing agents. The inorganic oxidizing agent is typically a salt. The organic oxidizing agent is preferably an organic peroxide and a halogenated hydantoin.
Inorganic salts suitable as oxidizing agents in the practice of the present invention include persulfates, permanganates, hypochlorites, hypobromites, chlorites, chlorates, bromates and perchlorates, preferably permanganates, hypochlorites and chlorates. Preferably, these salts are their alkali metal, alkaline earth metal and/or ammonium salts, more preferably the salts are alkali metal salts.
Suitable inorganic salts for use as oxidizing agents in the practice of the present invention include ammonium persulfate, sodium persulfate, potassium persulfate, sodium permanganate, potassium permanganate, ammonium hypochlorite, sodium hypochlorite, potassium hypochlorite, magnesium hypochlorite, calcium hypochlorite, ammonium hypobromite, sodium hypobromite, potassium hypobromite, calcium hypobromite, ammonium chlorite, sodium chlorite, potassium chlorite, calcium chlorite, ammonium chlorate, sodium chlorate, potassium chlorate, ammonium bromate, sodium bromate, potassium bromate, ammonium perchlorate, sodium perchlorate, and potassium perchlorate.
Preferred inorganic oxidizing agents include alkali metal permanganates, alkali metal hypochlorites and alkaline earth metal chlorates. More preferred inorganic oxidizing agents are sodium permanganate, potassium permanganate, sodium hypochlorite, potassium hypochlorite, magnesium chlorate and calcium chlorate. Even more preferred inorganic oxidizing agents are potassium permanganate, sodium hypochlorite and calcium chlorate.
The organic oxidizing agent as the organic peroxide has a hydrocarbon group containing four to about twelve carbon atoms, preferably four to about ten carbon atoms, in each group, and the hydrocarbon group may be the same or different and may be an alkyl group (linear, branched, or cyclic), an aryl group, or an aralkyl group. Preferred hydrocarbon groups are branched alkyl groups and aralkyl groups. Suitable hydrocarbyl groups include tert-butyl, 1-dimethylpropyl, 1-dimethylbenzyl and 1, 1-dimethyl-4-methylphenyl, with tert-butyl and 1, 1-dimethylpropyl being preferred. Suitable organic peroxides include di-t-butyl peroxide, bis (1, 1-dimethylpropyl) peroxide, t-butyl 1, 1-dimethylbenzyl peroxide, t-butyl 1, 1-dimethyl-4-methylphenyl peroxide, and bis (1, 1-dimethylbenzyl) peroxide. Preferred organic peroxides include di-t-butyl peroxide.
The organic oxidizing agents used as halogenated hydantoins are halogenated 5-hydrocarbyl hydantoins and halogenated 5, 5-dihydrocarbyl hydantoins, which are 1, 3-dibromo-derivatives, 1, 3-dichloro-derivatives and/or N, N' -bromochloro-derivatives (or 1, 3-bromochloro derivatives) of 5-hydrocarbyl hydantoin and 5, 5-dihydrocarbyl hydantoin. Halogenated 5, 5-dihydrocarbyl hydantoins are preferred. More preferred halogenated hydantoins are halogenated 5-alkyl hydantoins and halogenated 5, 5-dialkyl hydantoins, especially those in which each alkyl group contains up to about 6 carbon atoms. Still more preferred are halogenated 5, 5-dialkylhydantoins in which each alkyl group independently contains up to 3 carbon atoms. Particularly preferred is a halogenated 5, 5-dimethylhydantoin.
Suitable hydantoins include 5-methylhydantoin, 5-ethylhydantoin, 5- (1-propyl) hydantoin, 5- (2-methylpropyl) hydantoin, 5- (2-butyl) hydantoin, 5-phenylhydantoin, 5-ethyl-5-methylhydantoin, 5-methyl-5- (2-methylpropyl) hydantoin, 5-ethyl-5- (2-methylpropyl) hydantoin, 5-methyl-5-phenylhydantoin, 5-ethyl-5-phenylhydantoin, 5-benzyl-5-methylhydantoin, 5-dimethylhydantoin and 5, 5-diethylhydantoin, preferably 5, 5-dimethylhydantoin and 5, 5-diethylhydantoin, especially 5, 5-dimethylhydantoin.
Preferred halogenated hydantoins are 1, 3-chloro-5, 5-dimethylhydantoin, 1, 3-bromo-5, 5-dimethylhydantoin and 1, 3-dibromo-5, 5-dimethylhydantoin, more preferably 1, 3-bromo-5, 5-dimethylhydantoin and 1, 3-dibromo-5, 5-dimethylhydantoin, especially 1, 3-dibromo-5, 5-dimethylhydantoin.
Mixtures of any two or more oxidizing agents may be used, including mixtures containing two or more inorganic oxidizing agents, mixtures containing two or more organic oxidizing agents, and mixtures of one or more inorganic oxidizing agents and one or more organic oxidizing agents. Preferably, the oxidizing agent is one or an inorganic oxidizing agent.
The oxidizing agent and halogen-containing sorbent are typically used in amounts of about 1:1 to about 1:25, preferably about 1:2 to about 1:20, more preferably about 1:3 to about 1:15, even more preferably about 1:3 to about 1:10, by weight of the oxidizing agent to halogen-containing sorbent. The preferred amount of oxidizing agent may vary with the amount of elemental mercury present in the material being treated.
Mercury and other environmental contaminants are adsorbed onto or removed by halogen-containing sorbents, particularly halogen-containing activated carbon, more particularly iodine-containing sorbents and bromine-containing sorbents, more particularly bromine-containing carbonaceous sorbents, and still more particularly bromine-containing activated carbon. Different halogen (especially bromine) morphologies (species) may be formed on halogen-containing sorbents (especially bromine-containing sorbents, especially bromine-containing activated carbons). For example, bromine (one bromine form) can oxidize elemental mercury and form mercury bromide, which can be adsorbed into the pores of the activated carbon, another form, bromide ions, which can be chemically bonded to ionic mercury to adsorb onto the surface of the activated carbon, and another component can catalyze mercury oxidation and enhance stabilization or adsorption of the oxidized mercury product.
The oxidizing agent used according to the invention may oxidize elemental mercury, causing the oxidized mercury to bond with halogen atoms on the sorbent and/or be absorbed into pores of the matrix material of the halogen-containing sorbent.
Some halogen-containing sorbents, particularly halogen-containing activated carbon, particularly iodine-containing sorbents and bromine-containing sorbents, more particularly bromine-containing carbonaceous sorbents, particularly bromine-containing activated carbon, can physically and chemically adsorb mercury in different oxidation states, including elemental mercury, oxidized mercury, and organic mercury. Mercury adsorbed on halogen-containing activated carbon, particularly bromine-containing activated carbon, is stable over a wide range of pH values, where "stable" means that the mercury does not separate from the adsorbent in appreciable amounts after adsorption.
The halogen-containing sorbents and oxidants used in the methods of the invention can be combined with other optional components such as pH buffers (including, for example and without limitation, ammonium carbonate, metal carbonates, ammonium phosphate, and metal phosphates), carriers (including, for example and without limitation, sand and mud), binders (including, for example and without limitation, mud, clay, and polymers), and/or other additives (including, for example and without limitation, iron compounds and sulfur compounds).
In the practice of the present invention, the halogen-containing sorbent and oxidizer may be used in a variety of forms, including as a dry solid or in combination with a suitable fluid, such as in the form of a slurry. The term "suitable fluid" as used herein means fluids such as water and other fluids. Those skilled in the art will appreciate in view of the teachings of the present disclosure that the selection of an appropriate fluid will depend on variables such as the composition of the substance, the composition of environmental contaminants present in the substance, and the like.
A blend comprising a halogen-containing sorbent and an oxidizing agent capable of oxidizing elemental mercury is a composition of the invention and is formed by a process comprising combining a matrix material, a halogen-containing compound, and an oxidizing agent in any order. When mixing is performed sequentially, the matrix material is preferably combined with a halogen-containing compound to form a halogen-containing sorbent, which is then combined with an oxidizing agent. Dry blending of ingredients is a convenient method for combining ingredients. In some embodiments in which the halogen-containing compound is a salt (such as an alkali metal halide), the halogen-containing compound may be combined with the adsorbent by incipient wetness techniques, and the halogen-containing adsorbent may be dried prior to contact with the oxidizing agent. The matrix material, halogen-containing compound, oxidizing agent, their amounts and their preferences are as described above.
Some treatments of the substance may be performed in situ and ex situ. Here, "in situ" refers to a process performed without moving a substance from its place. Examples of in situ treatments include injection of the halogen-containing sorbent into the soil (typically a slurry) or mechanical mixing of the halogen-containing sorbent with the soil. Similarly, "ex situ" refers to a process performed during or after removal of a substance from its location, after which the substance may or may not return to its location.
Thermal desorption and retorting are two common ex situ heat treatment methods for mercury remediation. This technique heats the contaminated medium to volatilize mercury and then condenses the vapor into liquid elemental mercury. Halogen-containing sorbents and oxidants can be used to adsorb mercury as an alternative to liquid mercury condensers or to remove mercury from the tail gas exiting the condenser.
In some applications, the halogen-containing sorbent and the oxidizing agent will remain in or with the substance. In other applications, the adsorbent and any remaining oxidant may be collected after use. When the halogen-containing adsorbent is collected after use, the adsorbent may be disposed of, or regenerated and reused.
The substance containing one or more environmental pollutants is a solid, a liquid, or a combination of a solid and a liquid, or a combination of one or more solids and one or more liquids. When the substance is a solid, it may comprise more than one solid. When the substance is a liquid, it may contain more than one liquid.
In some methods of the invention, the use of the halogen-containing sorbent and the oxidizer, whether applied to a substance comprising one or more solids, one or more liquids, or a combination of at least one solid and at least one liquid, can be separate repair pathways or can supplement the use of other repair methods. In other methods according to the invention, a halogen-containing adsorbent and an oxidizing agent may be used in addition to one or more other repair agents in the same repair procedure.
The addition of a halogen-containing adsorbent and an oxidizing agent to the contaminated waste adsorbs one or more contaminants. In some embodiments, a halogen-containing sorbent and an oxidizing agent remain in the substance to stabilize and/or cure the substance. In other embodiments, the combined halogen-containing sorbent, oxidizer, and material are often placed in a landfill with binders and other compounds.
The term "solid(s)" and/or solids (solids) as used herein includes, but is not limited to, soil, debris, waste, and other such materials known to those skilled in the art. Soil is the preferred solid to be treated in the practice of the present invention.
The method of the present invention is provided for reducing the environmental effectiveness of at least a portion of one or more environmental contaminants in a solid comprising one or more environmental contaminants. The substance as a solid is sometimes referred to herein as a solid substance.
The addition and/or application of the halogen-containing sorbent and the oxidizer to the solid may include:
(a) Injecting a halogen-containing adsorbent and an oxidizing agent into the solid, optionally through holes and/or wells and/or channels (whether already present or created manually, e.g., by drilling holes into the material) present in the material, and/or
(B) Applying a halogen-containing adsorbent and an oxidizing agent to the surface of the solid, and/or
(C) Combining a halogen-containing adsorbent and an oxidizing agent with at least a portion of the surface of the solid, and/or
(D) Placing a halogen-containing adsorbent and an oxidant in a vacuum well for treating the solid, and/or
(E) Adding a halogen-containing adsorbent and an oxidizing agent to the contained solids, and/or
(F) Combining a halogen-containing adsorbent and an oxidant with a solid, and/or
(G) Adding a halogen-containing sorbent and an oxidant to the reaction barrier, and/or
(H) Forming a reaction barrier containing a halogen-containing sorbent and an oxidizing agent.
Combining the halogen-containing sorbent and the oxidizing agent with the surface of the solid as in (c) above may be performed by combining the halogen-containing sorbent and the oxidizing agent with a portion of the solid and then applying the combination of the sorbent, the oxidizing agent and the solid to the surface of the solid, or by combining the halogen-containing sorbent and the oxidizing agent with the surface of the solid.
Some preferred methods of adding and/or applying the halogen-containing sorbent and the oxidizing agent to the solid are:
(a) Injecting a halogen-containing sorbent and an oxidizing agent into the solid;
(b) Applying a halogen-containing adsorbent and an oxidizing agent to the surface of the solid, and/or
(C) The halogen-containing sorbent and the oxidizing agent are combined with at least a portion of the surface of the solid.
Embodiments of treating a solid to reduce the environmental effectiveness of one or more environmental pollutants involve (i) drilling, and/or channeling in the solid, (ii) covering the surface of the solid with a halogen-containing sorbent layer and an oxidizing agent, and (iii) heating portions of the solid to cause migration of the one or more environmental pollutants (e.g., mercury) to the surface having the halogen-containing sorbent and the oxidizing agent thereon.
Another embodiment of treating a solid to reduce the environmental effectiveness of one or more environmental pollutants involves (i) drilling, and/or channeling holes in the solid, (ii) filling some of the holes or channels with a halogen-containing adsorbent and an oxidizing agent, and (iii) purging heated air into the holes or channels to migrate one or more environmental pollutants (e.g., mercury) to the holes filled with the halogen-containing adsorbent and the oxidizing agent.
In some embodiments of the invention, the solid is heated in the vacuum well to vaporize environmental contaminants (e.g., mercury), and when a halogen-containing adsorbent and an oxidizing agent are present in the vacuum well as in (d) above, the halogen-containing adsorbent and the oxidizing agent may together absorb one or more of the vaporized environmental contaminants. In these procedures, a halogen-containing adsorbent and an oxidizer are placed in a vacuum well and brought into contact with steam generated in the vacuum well at one or more locations before the steam is vented to the atmosphere. One application of this procedure is for Soil Vapor Extraction (SVE) for mercury remediation, and a halogen-containing adsorbent, particularly a bromine-containing activated carbon, may be placed in a vacuum well with an oxidizing agent to adsorb mercury.
In certain types of solid material soil, the halogen-containing sorbent and oxidizer may be used to immobilize mercury prior to or during stabilization and solidification (S/S) of the soil in situ and/or ex situ treatments. An ex situ process adds a halogen-containing sorbent, an oxidizing agent, one or more binders and other components to the contaminated material and mixes them together in a reactor. The mixture is then stabilized and cemented or placed in a landfill. In some embodiments, powdered activated carbon containing bromine may be used with an oxidizing agent in an S/S treatment process. Mercury adsorbed by bromine-containing powdered activated carbon is stable during the manufacture and curing of concrete. This is advantageous because fly ash and cement are typical binders used in S/S technology.
In another embodiment of the present invention, a halogen-containing adsorbent, particularly a powdered activated carbon containing bromine, is applied on top of the contaminated soil along with an oxidizing agent as a remediation agent for mercury contaminated soil. In this method, the soil is undisturbed and a halogen-containing adsorbent (especially bromine-containing activated carbon) is present with the oxidizing agent at the top layer of the soil and inhibits migration of mercury from the soil.
The halogen-containing adsorbent, particularly bromine-containing activated carbon, may be mixed with an oxidizing agent along with another agent to produce a mixture that improves penetration of the halogen-containing adsorbent into solids, particularly soil. The halogen-containing adsorbent may be added in an amount less than 10% of the soil surface layer, the oxidizing agent may be in an amount up to 10% of the soil surface layer, and the soil surface layer may have a thickness up to 10cm. In some embodiments, a pH adjuster is also applied, either alone or in combination with the halogen-containing sorbent and the oxidizer, optionally together with an agent that improves penetration of the halogen-containing sorbent and the oxidizer into the solid.
The method of the present invention is provided for reducing the environmental effectiveness of at least a portion of one or more environmental contaminants in a liquid comprising the one or more environmental contaminants. The term "liquid (liquid) and/or liquids (liquids)" as used herein includes, but is not limited to, ground water, waste water, surface water, brine, fresh water (e.g., lakes, ponds) and other such substances known to those skilled in the art. Substances that are liquids are sometimes referred to herein as liquid substances.
The addition and/or application of the halogen-containing sorbent and the oxidizer to the liquid may include:
(a) Injecting a halogen-containing adsorbent and an oxidizing agent into the liquid, filtering the adsorbent used and any remaining oxidizing agent if necessary, and/or
(B) Applying a halogen-containing adsorbent and an oxidizing agent to the surface of the liquid, and/or
(C) Combining a halogen-containing adsorbent and an oxidizing agent with a liquid, and/or
(D) Passing the liquid through a fixed bed comprising a halogen-containing adsorbent and an oxidant, and/or
(E) Passing the liquid through a filter comprising a halogen-containing adsorbent and an oxidizing agent, and/or
(F) Pumping the liquid through a fixed bed or column containing a halogen-containing adsorbent and an oxidant, and/or
(G) A halogen-containing sorbent and an oxidizing agent are added to the contained volume of liquid.
Combining the halogen-containing sorbent and the oxidizer with the liquid as in (c) above may be performed by combining the halogen-containing sorbent and the oxidizer with a bulk liquid (bulkliquid), or by combining the halogen-containing sorbent and the oxidizer with a portion of the liquid to form a slurry, and then combining the slurry with the remaining liquid.
Some materials are a combination of at least one solid and at least one liquid, and include sludge, slurry, sediment, pore water (e.g., soil pore water or sediment pore water), and other combinations of solids and liquids. Sediment, soil pore water and sediment pore water are preferred combination materials to be treated in the practice of the present invention. These combinations are sometimes referred to as multiphase materials. The method of the present invention is provided for reducing the environmental effectiveness of at least a portion of one or more environmental pollutants in a combination comprising one or more environmental pollutants. The substances as a combination are sometimes referred to herein as a combination substance.
Adding and/or applying the halogen-containing sorbent and the oxidizing agent to the combination may include adding and/or applying the halogen-containing sorbent and the oxidizing agent to the combination. In such methods, adding and/or applying the halogen-containing sorbent and the oxidizing agent to the combination may include:
(a) Injecting a halogen-containing adsorbent and an oxidizing agent into the combination, optionally through holes and/or wells and/or channels (whether already present or created manually, e.g., created by drilling holes in the combination) present in the substance, and/or
(B) Applying a halogen-containing adsorbent and an oxidizing agent to the combined surface, and/or
(C) Combining a halogen-containing adsorbent and an oxidizing agent with at least a portion of the combined surface as described above for solid and/or liquid materials, and/or
(D) Combining a halogen-containing adsorbent and an oxidizing agent with the combination, and/or
(E) Placing a halogen-containing adsorbent and an oxidant in a vacuum well treating the combination in a manner similar to that described for the solid material, and/or
(F) Adding a halogen-containing adsorbent and an oxidizing agent to the contained combination, and/or
(G) Coating the surface of the material with a layer comprising a halogen-containing adsorbent and an oxidizing agent, and/or
(H) Placing a halogen-containing adsorbent and an oxidizing agent in the lid, and/or
(I) Adding a halogen-containing sorbent and an oxidant to the reaction barrier, and/or
(J) Forming a reaction barrier containing a halogen-containing sorbent and an oxidant, and/or
(K) A halogen-containing adsorbent and an oxidizing agent are placed in the geotextile mat.
Combining the halogen-containing sorbent and the oxidizing agent with the combination as in (d) above may be performed by combining the halogen-containing sorbent and the oxidizing agent with the combination, or by combining the halogen-containing sorbent and the oxidizing agent with a portion of the combination to form a mixture and then combining the mixture with the combined surface. In these embodiments, the halogen-containing sorbent may include, for example, but is not limited to, a halogen-containing activated carbon sorbent, preferably a bromine-containing activated carbon sorbent, more preferably a bromine-containing activated carbon sorbent.
Some preferred methods of adding and/or applying the halogen-containing sorbent and the oxidizing agent to the combination are:
(a) Injecting a halogen-containing sorbent and an oxidizing agent into the combination;
(b) Applying a halogen-containing sorbent and an oxidizing agent to the combined surface;
(c) Combining a halogen-containing adsorbent and an oxidizing agent with at least a portion of the combined surface, and/or
(D) A halogen-containing sorbent and an oxidizing agent are combined with the combination.
As will be apparent to those skilled in the art, many variables must be considered regarding the use of the present invention depending on the substance being treated. In all methods of the present invention, whether applied to solids, liquids, or combinations thereof, one of ordinary skill in the art, in view of the teachings herein, will know how to determine the amount of halogen-containing sorbent to be used, whether to use an optional component in combination with the sorbent, the particular optional component and amount thereof that will result in a benefit if so, the number of applications of the method of the present invention that will result in a benefit, and the time interval between such applications, whether to use the method of the present invention in combination with known remediation methods, if so, how to obtain a beneficial result, and so forth.
The following examples are presented for illustrative purposes and are not intended to impose limitations on the scope of the invention.
Example 1
The NaBr-containing adsorbent (NaBr-PAC) was formed by impregnating NaBr dissolved in water onto powdered activated carbon (PAC; 10.24g NaBr/100g PAC) using incipient wetness impregnation, and then drying the mixture in an oven at 105℃overnight to give a bromine loading of 8% by weight in the NaBr-PAC adsorbent. The blend of NaBr-PAC and oxidant is formed by dry blending NaBr-PAC adsorbent with a different oxidant in a weight ratio of NaBr-PAC to oxidant of 5:1.
Chloralkali soil containing elemental mercury, organomercury, and other contaminants is treated with various adsorbents by dry blending each adsorbent with a portion of the soil. Each portion was mixed with water to extract water as a soil extract, and each soil extract sample was analyzed. The amount of mercury present in the leachate of the treated soil was determined by cold vapor atomic absorption (CVAA; atomic absorption mercury spectrometer with Zeeman (Zeeman) background correction, ohio Lumex co., model RA 915+) in an atomic absorption spectrometer with a mercury vapor analyzer. The results are summarized in table 1.
TABLE 1
1 Comparative example.
2 Relative to the weight of the soil being treated.
3 Average of two runs.
4 Formed from elemental bromine and PAC.
5 Bd=below detection limit (1 μg/kg).
The results summarized in Table 1 demonstrate that the blend of NaBr-PAC and oxidant provides performance comparable to Br-PAC in terms of reducing leachable mercury after treatment.
Other embodiments of the invention include, but are not limited to:
a) A method for reducing the environmental effectiveness of at least a portion of one or more environmental pollutants in a substance comprising one or more environmental pollutants, the method comprising
Adding and/or applying a halogen-containing sorbent and an oxidizing agent capable of oxidizing elemental mercury to the substance, wherein the halogen-containing sorbent comprises one or more halogens selected from chlorine, bromine and/or iodine and one or more matrix materials,
Thereby reducing the environmental effectiveness of at least a portion of one or more environmental pollutants in the substance.
B) The method as in a), wherein the halogen-containing sorbent comprises a matrix material selected from one or more carbonaceous materials, and/or wherein the halogen-containing sorbent comprises a matrix material selected from one or more inorganic materials.
C) The method according to B), wherein the carbonaceous material is activated carbon, and/or wherein the inorganic material is selected from the group consisting of inorganic oxides, natural zeolites, inorganic carbonates and clay minerals.
D) The method according to B) or C), wherein the inorganic material is selected from chabazite, silica, kaolinite, and bentonite.
E) The method of any one of a) to D), wherein the halogen-containing adsorbent is a bromine-containing adsorbent.
F) The method of A), wherein the halogen-containing adsorbent is a halogen-containing activated carbon adsorbent.
G) The method of A), wherein the halogen-containing adsorbent is a bromine-containing activated carbon adsorbent.
H) The method of any one of a) to G), wherein the halogen-containing sorbent has a halogen content of about 0.1 wt% to about 50 wt%, calculated as bromine and based on the total weight of the halogen-containing sorbent.
I) The method of any one of a) to G), wherein the oxidizing agent is an inorganic oxidizing agent, and/or wherein the oxidizing agent is an organic oxidizing agent.
J) The method according to I), wherein
The inorganic oxidant is permanganate, hypochlorite and/or chlorate, and/or wherein the inorganic oxidant is an alkali metal salt, alkaline earth metal salt and/or ammonium salt, and/or
Wherein the organic oxidizer is an organic peroxide or a halogenated hydantoin.
K) The method according to I), wherein
The inorganic oxidant is alkali metal permanganate, alkali metal hypochlorite and/or alkaline earth metal chlorate, and/or
When the oxidizing agent is an organic peroxide, the organic peroxide has branched alkyl groups and/or aralkyl groups, and wherein when the oxidizing agent is a halogenated hydantoin, the halogenated hydantoin is a halogenated 5, 5-dihydrocarbyl hydantoin.
L) the process according to I), wherein
The inorganic oxidant is potassium permanganate, sodium hypochlorite and/or calcium chlorate, and/or
The organic oxidizer is selected from t-butyl peroxide, 1, 3-bromochloro-5, 5-dimethylhydantoin and 1, 3-dibromo-5, 5-dimethylhydantoin.
M) the method of any one of a) to L), wherein the one or more environmental contaminants are mercury, chromium, arsenic and/or selenium.
N)) according to any one of a) to M), wherein the substance comprising the environmental contaminant is a solid, and wherein adding and/or applying the halogen-containing adsorbent and oxidant to the solid comprises:
(a) Injecting a halogen-containing sorbent and an oxidizing agent into the solid;
(b) Applying a halogen-containing sorbent and an oxidizing agent to the surface of the solid;
(c) Combining a halogen-containing sorbent and an oxidizing agent with at least a portion of the surface of the solid;
(d) Placing a halogen-containing adsorbent and an oxidant in a vacuum well that processes the solids;
(e) Adding a halogen-containing sorbent and an oxidizing agent to the contained solids;
(f) Combining a halogen-containing sorbent and an oxidizing agent with the solid;
(g) Adding a halogen-containing adsorbent and an oxidant to the reaction barrier, and/or
(H) Forming a reaction barrier containing a halogen-containing sorbent and an oxidant;
optionally wherein the solid is soil.
O) the method according to any one of a) to M), wherein the substance comprising the environmental contaminant is a liquid, and wherein adding and/or applying the halogen-containing adsorbent and oxidant to the liquid comprises:
(a) Injecting a halogen-containing adsorbent and an oxidizing agent into the liquid;
(b) Applying a halogen-containing sorbent and an oxidizing agent to the surface of the liquid;
(c) Combining a halogen-containing adsorbent and an oxidizing agent with the liquid;
(d) Passing the liquid through a fixed bed comprising a halogen-containing adsorbent and an oxidant;
(e) Passing the liquid through a filter comprising a halogen-containing adsorbent and an oxidant;
(f) Pumping the liquid through a fixed bed or column containing a halogen-containing adsorbent and an oxidant, and/or
(G) A halogen-containing sorbent and an oxidizing agent are added to the contained volume of liquid.
P) the method according to any one of a) to M), wherein the substance comprising the environmental contaminant is a combination of at least one solid and at least one liquid, and wherein adding and/or applying the halogen-containing adsorbent and oxidant to the combination comprises:
(a) Injecting a halogen-containing sorbent and an oxidizing agent into the combination;
(b) Applying a halogen-containing sorbent and an oxidizing agent to the combined surface; (c) combining a halogen-containing sorbent and an oxidizing agent with at least a portion of the combined surfaces;
(d) Combining the halogen-containing sorbent and the oxidizing agent with the combination;
(e) Placing the halogen-containing sorbent and oxidizer in a vacuum well that treats the combination;
(f) Adding the halogen-containing sorbent and the oxidizing agent to the contained combination;
(g) Covering the surface of the substance with a layer comprising a halogen-containing adsorbent and an oxidizing agent;
(h) Placing a halogen-containing sorbent and an oxidizer in the lid;
(i) Adding a halogen-containing sorbent and an oxidant to the reaction barrier;
(j) Forming a reaction barrier containing a halogen-containing sorbent and an oxidant, and/or
(K) A halogen-containing adsorbent and an oxidizing agent are placed in the geotextile mat.
Q) the method according to P), wherein the adding and/or applying comprises:
(a) Injecting a halogen-containing sorbent and an oxidizing agent into the combination;
(b) Applying a halogen-containing sorbent and an oxidizing agent to the combined surface;
(c) Combining a halogen-containing adsorbent and an oxidizing agent with at least a portion of the combined surface, and/or
(D) Combining a halogen-containing sorbent and an oxidizing agent with the combination;
optionally wherein the combination is a deposit.
R) the process according to Q), wherein the halogen-containing adsorbent comprises a matrix material, which is activated carbon.
S) the method according to A), wherein the substance is soil or sediment, wherein the halogen-containing adsorbent is a bromine-containing activated carbon adsorbent, and wherein the oxidizing agent is sodium hypochlorite, potassium bromate, or calcium chlorate.
T) the method according to Q), wherein
The oxidizing agent is an inorganic oxidizing agent, and the inorganic oxidizing agent is an alkali metal permanganate, alkali metal hypochlorite and/or alkaline earth metal chlorate, and/or
The oxidizing agent is an organic oxidizing agent, and when the organic oxidizing agent is an organic peroxide, the organic peroxide has branched alkyl groups and/or aralkyl groups, and wherein when the oxidizing agent is a halogenated hydantoin, the halogenated hydantoin is a halogenated 5, 5-dihydrocarbyl hydantoin.
(U) the method according to T, wherein
The inorganic oxidant is potassium permanganate, sodium hypochlorite and/or calcium chlorate, and/or
Wherein the organic oxidizer is selected from the group consisting of t-butyl peroxide, 1, 3-bromochloro-5, 5-dimethylhydantoin and 1, 3-dibromo-5, 5-dimethylhydantoin.
V) a blend of a halogen-containing sorbent and an oxidizing agent capable of oxidizing elemental mercury, wherein the halogen-containing sorbent comprises one or more halogens selected from chlorine, bromine, and/or iodine.
W) the blend according to V, wherein the halogen of the halogen-containing adsorbent is bromine and/or iodine, wherein the halogen-containing adsorbent comprises a matrix material selected from one or more carbonaceous materials, wherein when the oxidant is an inorganic oxidant, the oxidant is a permanganate, hypochlorite and/or chlorate, and/or wherein the oxidant is an alkali metal salt, alkaline earth metal salt and/or ammonium salt, and wherein when the oxidant is an organic oxidant, the oxidant is an organic peroxide or a halogenated hydantoin.
X) a process for forming a blend of a halogen-containing sorbent and an oxidizing agent capable of oxidizing elemental mercury, the process comprising:
a) i) combining a halogen-containing compound and a matrix material to form a halogen-containing sorbent, and ii) combining the halogen-containing sorbent with an oxidizing agent, or
B) A halogen-containing sorbent and an oxidizer are combined.
Y) the process according to X), wherein when the halogen of the halogen-containing adsorbent is bromine, the matrix material is a carbonaceous material, wherein when the oxidizing agent is an inorganic oxidizing agent, the inorganic oxidizing agent is a permanganate, hypochlorite and/or chlorate, and/or wherein the inorganic oxidizing agent is an alkali metal salt, alkaline earth metal salt and/or ammonium salt, and wherein when the oxidizing agent is an organic oxidizing agent, the organic oxidizing agent is an organic peroxide or a halogenated hydantoin.
Z) the method according to Y), wherein
The inorganic oxidant is alkali metal permanganate, alkali metal hypochlorite and/or alkaline earth metal chlorate and/or
When the oxidizing agent is an organic oxidizing agent, the organic peroxide has branched alkyl groups and/or aralkyl groups when the organic oxidizing agent is an organic peroxide, and wherein when the organic oxidizing agent is a halogenated hydantoin, the halogenated hydantoin is a halogenated 5, 5-dihydrocarbyl hydantoin.
AA) the method according to Z), wherein
The inorganic oxidant is potassium permanganate, sodium hypochlorite and/or calcium chlorate, and/or
The organic oxidizer is selected from t-butyl peroxide, 1, 3-bromochloro-5, 5-dimethylhydantoin and 1, 3-dibromo-5, 5-dimethylhydantoin.
AB) the method according to any one of Y) to AA), wherein the matrix material is activated carbon.
Components referred to by chemical name or formula anywhere in the specification or claims hereof, whether referred to in the singular or plural, are identified as they exist prior to coming into contact with another substance referred to by chemical name or chemical type (e.g., another component, a solvent, etc.). It is not important what chemical changes, transformations and/or reactions, if any, take place in the resulting mixture or solution as such changes, transformations and/or reactions are the natural result of bringing the specified components together under the conditions called for pursuant to this disclosure. Thus, the components are identified as being brought together to perform the desired operation or as forming an ingredient of the desired composition. Furthermore, although the claims below may refer to substances, components and/or ingredients at the present time ("comprises", "is" etc.), the reference to substances, components or ingredients means that they are present at the same time just prior to first contacting, blending or mixing with one or more other substances, components and/or ingredients in accordance with the present disclosure. Thus, the fact that a substance, component or ingredient may lose its original properties through chemical reaction or transformation during the course of a contacting, blending or mixing operation is not of practical significance, given the present disclosure and given the ordinary skill of the chemist.
The present invention can include, consist of, or consist essentially of the materials and/or procedures described herein.
As used herein, the term "about" modifying the amount of an ingredient in a composition of the invention or an ingredient used in a method of the invention refers to, for example, a change in the amount of a numerical value that may occur during typical measurement and liquid handling procedures used in the real world to prepare concentrates or use solutions, errors due to negligence in such procedures, differences in the manufacture, source or purity of the ingredient used to prepare the composition or to perform the method, and the like. The term about also encompasses amounts that differ due to different equilibrium conditions of the composition resulting from a particular initial mixture. Whether or not modified by the term "about," the claims include equivalents to the quantities.
The article "a" or "an" (if used herein and as used herein) is not intended to limit the description or claims to the single element referred to by the article and should not be construed as limiting the description or claims to the single element referred to by the article unless specifically indicated otherwise. Conversely, the article "a/an" (if used herein and as used herein) is intended to cover one or more of such elements unless the context clearly indicates otherwise.
The invention is susceptible to considerable variation in its practice. Accordingly, the foregoing description is not intended to limit the invention to the particular exemplifications presented hereinabove and should not be construed as limiting the invention to the particular exemplifications presented hereinabove.