A+B
C+D.
One drives the reaction to the right by removing either or both of C and D as they are formed and providing excess A and/or B.
For the catalysts to operate with the higher degree of selectivity required to shift the products to the desired end products, supercritical conditions provide increased reactions kinetics and appear to be necessary. Therefore to make methanol (Tc=239° C., Pc=79.9 atm), ethanol (Tc=243° C., Pc=62.96 atm), n-propyl alcohol (Tc=263.6° C., Pc=51.0 atm), iso-propyl alcohol (Tc=235.16° C., Pc=47.0 atm) in high yield while limiting the water in the product stream, it is necessary to stay above the critical pressure or temperature.
A fluid can be kept in the supercritical state by exceeding either the supercritical temperature or supercritical pressure. Exceeding the supercritical pressure is useful because the average distance between molecules is reduced. Reactions in a vessel are easier to maintain with the desired conditions by controlling the pressure under isothermal temperature conditions.
In the complex systems of this instant invention the supercritical temperature and supercritical pressure are of the entire mixture since the entire fluid mixture is either supercritical or not. An explanation of the nature of the supercritical state is given in “Fundamentals of Classical Thermodynamics” by Gordon J. Van Wylen and Richard E. Sonntag, John Wiley and Sons. Inc., Second Edition, 1973, pp. 42-43. The means of determining the supercritical properties of mixtures is explained by Robert C. Reid, John M. Prausnitz and Bruce E. Poling in “The Properties of Gases & Liquids”, Fourth Edition, Mc-Graw-Hill, 1987Chapter 5, pp. 121-135.
A catalyst that operates by removing the products that are formed from the reaction interface through use of the energy or spacing of molecules in a supercritical state is affected by the state of the entire system. In the fixed volume reactor the supercritical state is maintained by controlling pressure and temperature and then allowing kinetics (the rate at which the reactions proceed) and the removal of the products by adsorption on the catalyst to define the composition of the mixture.
A thermodynamic analysis is useful as a first step because the analysis indicates the distribution of products from a mixture of chemicals at a specific temperature, pressure, and volume in the absence of removing the products as the products are formed. Table 1 is an example of the potential equilibrium distribution of the noted gases when the ratios of the input feed materials have a ratio of C:H:O of 1:2:1. This table is calculated using standard thermodynamic functions for the noted products at the condition of equilibrium using the standard Free Energy Minimization technique. An example of the use of this technique can be found in Perry's Chemical Engineers' Handbook published by McGraw Hill. In the 1999 CD ROM version it is on pages 4-33-4-34.
Table 1 is a summary of such a calculation at 1250° K. (977° C.) and 1 atm pressure. The calculations must be performed for an assumed distribution of products. From experimental data it is known that the materials listed in Table 1 are usually found in such gases.

TABLE 1

Calculated Equilibrium for C:H:O 1:2:1 at 1250° K and 1 atm

	mol fraction	mol fraction	mass fraction
Species	in the phase	in the mixture	in mixture	Mols

(fluid phase)
CH₃OH	1.082E−09	1.075E−09	2.295E−09	2.150E−09
CO	4.945E−01	4.915E−01	9.170E−01	9.830E−01
CO₂	2.391E−03	2.377E−03	6.967E−03	4.754E−03
H₂	4.993E−01	4.963E−01	6.664E−02	9.925E−01
H₂O	3.759E−03	3.736E−03	4.483E−03	7.472E−03
O₂	6.651E−20	6.610E−20	1.409E−19	1.322E−19
(condensed
Phase)
C (Solid)	1.000E+00	6.113E−03	4.890E−03	1.223E−02

From the column (Table 1) of mass fractions in the mixture it is evident that the mixture is predominantly CO and H₂with some water and CO₂. There is some solid carbon but the fraction is small compared to CO and H₂. If the mixture is compressed quickly after filtering the solid Carbon, a state at 530° K. (257° C.) and 140 atm is achieved as shown in Table 2.

TABLE 2

Predicted Equilibrium for Table 1 Gas Phase at 530° K and 140 atm.

	mol fraction	mol	mass fraction		mass fraction
species	in the phase	fraction in mixture	in mixture	Mols	with catalyst

CH₃OH	2.468E−09	2.468E−09	4.390E−09	2.468E−09	3.553E−01
CO	1.533E−04	1.533E−04	2.384E−04	1.533E−04	1.537E−04
CO₂	0.000E+00	0.000E+00	0.000E+00	0.000E+00	0.000E+00
H₂	1.533E−04	1.533E−04	1.716E−05	1.533E−04	1.106E−05
H₂O	9.997E−01	9.997E−01	9.997E−01	9.998E−01	6.445E−01
O₂	3.928E−38	3.928E−38	6.977E−38	3.929E−38	4.498E−38

Thermodynamics predicts that there would be very little methanol (CH₃OH) in the mixture with most of the mass being converted to water. Although the mixture may have started out in the supercritical state as the mixture is cooled down with an increase in pressure, the mixture passes out of that state. The mixture's supercritical conditions are controlled by the massive amount of water that has Tc=374.2° C., Pc=218.3 atm.
The far right hand column (mass fraction with catalyst) of Table 2 indicates what happens if methanol is continually removed from the system via the catalysts such as described by Stevens '060, Hucul '858 or others while maintaining the same equilibrium ratios of the other products. From the state with the equilibrium thermodynamics being used a single time, when the methanol is removed continually via the catalyst the equilibrium thermodynamics is used repeatedly. The reaction is driven kinetically to form more methanol. The final values in the right hand column are typical of those actually seen with various catalysts. The calculated thermodynamics and kinetics in Table 2 indicate that 35% of the mixture could be methanol. Under these conditions a large quantity of water is produced but the catalyst delays the onset of the mixture leaving the supercritical state as the catalyst delays the water reaction and allows the methanol reaction to proceed.
The final solution is approximately ⅔ water and ⅓ methanol. In this case the critical pressure of methanol and water mixtures are shown inFIG. 2. It can be seen that when the mole fraction of methanol in the mixture is above about 0.20, the critical pressure will be below 2000 psia (136 atm.). The ratio of water to methanol in Table 2 is such that the methanol mole fraction is about 0.23. The calculation is done in Table 2 for 140 atm. The mixture never passes out of the supercritical state. In cases where the mixture starts in the supercritical state and passes out of such a state it is possible to make alcohols but the operating conditions objective in this instant invention is to keep the supercritical fluid in the supercritical state for the longest time possible during the actual reaction.
These calculations are given to aid in the explanation of how the system works and may not exactly define the actual values as the number of products that can be produced is large. If the species around ethanol are included in the calculation and some of the other possible hydrocarbons are added, then the results are as given in Table 3.

TABLE 3

Calculated Equilibrium at 530° K and 100 atm.

	mol fraction in	mol fraction in	mass fraction		mass fraction
species	the phase	mixture	in mixture	Mols	with catalysts

CH₃OH	6.356E−09	6.356E−09	3.710E−09	9.541E−09	3.099E−01
CH₄	4.993E−01	4.993E−01	3.752E−01	7.494E−01	1.531E−01
CO	8.948E−06	8.948E−06	1.174E−05	1.343E−05	4.792E−06
CO₂	1.669E−01	1.669E−01	3.441E−01	2.505E−01	1.404E−01
C₂H₂	5.650E−22	5.650E−22	6.891E−22	8.480E−22	2.812E−22
C₂H₄	1.099E−11	1.099E−11	1.444E−11	1.649E−11	5.892E−12
C₂H₄O	8.359E−12	8.359E−12	1.725E−11	1.255E−11	7.040E−12
C₂H₆	1.865E−05	1.865E−05	2.626E−05	2.799E−05	1.072E−05
C₂H₆O	3.735E−12	3.735E−12	8.060E−12	5.606E−12	2.820E−01
H₂	1.426E−03	1.426E−03	1.347E−04	2.140E−03	5.495E−05
H₂O	3.324E−01	3.324E−01	2.805E−01	4.990E−01	1.145E−01
O₂	7.030E−41	7.030E−41	1.054E−40	1.055E−40	4.300E−41
Acetic	3.093E−09	3.093E−09	8.701E−09	4.642E−09	3.551E−09
Acid

The amount of methanol produced by the catalytic continuous removal in this case is 31% and the ethanol is 28.2%. The same assumption of catalytic behavior was made as in Table 2 with the additional assumption that the catalyst was 350 times more selective for ethanol than methanol. This is similar to relative ratios seen with catalysts in the Stevens '060 and Hucul '858 patents.
The greater the variety of alcohols produced the easier it is to keep the systems supercritical because the concentration of water is less of the total produced mass. The ability to perform these calculations does not imply that these methods are predictive because each catalyst exhibits different behavior. While the outcomes can not be predicted, the calculations-offer a way of understanding the phenomena involved and thus allow better optimization than has been achieved in other processes to date.
The liquid and gas compositions of the reaction mixture in thecatalytic reactor6 can be monitored. The measured composition of the components can be used to calculate the supercritical pressure of the mixture and the pressure adjusted to maintain a pressure above the supercritical pressure.
An unexpected and novel feature of this instant invention is that the overall process produces no waste materials from thecatalytic reaction step6. Other processes have unreacted gases and unusable liquids that increase cost and present an environmental disposal problem. The unreacted exhaust gases in other processes are sent back through the catalytic reactor lowering the efficiency of the operation. In the instant invention any unreacted gases are sent back to the boiler orturbine3 to produce electricity and any unusable liquids are still combustible and these liquids are recycled to thegasifier2.
Another new and novel feature of this instant invention is thepurification scheme7 for the mixed alcohols from synthesis gas with varying levels of contaminating substances. When the mixed alcohols emerge from the reactor, the alcohols are hot, usually in a gaseous state and need cooling to be liquefied. Any substances with higher boiling points will condense first upon leaving thecatalytic reactor6 and then the lower boiling alcohols can be collected. The substances that are found not to be suitable for alcohol fuels can be sent back into thegasifier2 and the emerging gases that did not convert to mixed alcohols are sent back to theturbine3. This reutilization of unreacted substances makes an otherwise difficult process of producing alcohols via gas reforming economically possible.
In another aspect if aseparate distillation column7 for the alcohol separation was used after the mixed alcohol production, the “non alcohol fuel” fractions are sent back to thegasifier2 for reprocessing.
The stream of synthesis gas that is utilized for the mixed alcohol production could be sent to a different process to be used for the production of other chemical entities such as hydrocarbons, ethers, or esters.
Unexpectedly the only waste products from this treatment process of MSW are the glass, sand, metals, and other similar solids out of thefirst stage1 and the normal boiler orturbine3 output gases that meet all present environmental standards. Any ash that comes from thegasification process step2 is combined with similar material from the first stage (front end processing1). Surprisingly virtually all of the oxidizable substances except for the non-oxidizable ash in the MSW is converted to useful products.
While the above description contains many particulars, these should not be considered limitations on the scope of the disclosure, but rather a demonstration of embodiments thereof. The process and methods disclosed herein include any combination of the different species or embodiments disclosed. Accordingly, it is not intended that the scope of the disclosure in any way be limited by the above description. The various elements of the claims and claims themselves may be combined in any combination, in accordance with the teachings of the present disclosure, which includes the claims.

Production of Alcohol

The process of mixed alcohol synthesis was carried out by passing a mixture of carbon monoxide and hydrogen over a catalyst. In the presence of the catalyst, the two gases reacted to produce alcohols, with either water or carbon dioxide as a by-product. To be efficient, the catalyst must yield a high weight ratio of product per unit weight of catalyst in a given period of time. An additional requirement is that the catalyst must be stable and active over a long period of time.
Among the various catalysts, Mo-based catalysts are considered to have the highest selectivity for formation of alcohols. MoS₂-based catalysts, first developed by Dow Chemicals, exhibit high resistance to sulfur poisoning. It has been reported that the addition of cobalt to the alkali-promoted MoS₂enhances the selectivity of ethanol. Potassium carbonate has shown to work as a best cation additive for alcohol selectivity. The optimum K₂CO₃loading on MoS₂catalyst has been reported as 17%.
The catalyst was prepared by mixing and grinding the three ingredients, CoS, MoS₂and K₂CO₃, then coating the mixture on alumina pellets. A tablet agent was used to aid the coating process.

EXAMPLE A

Pressure of 500 psi

250 grams of catalyst (64% MoS₂/18.4% CoS/17% K₂CO₃supported on alumina beads) were placed in a one liter stainless steel high pressure reactor. The weight of the active component (MoS₂/CoS/K₂CO₃) of the catalyst was 50 grams. Premixed carbon monoxide and hydrogen gas (CO: H_2;1:1) was passed through the catalyst bed at 500 psi and 260° C., at a flow rate of 5 liters/min. The reaction products were passed through a condenser where alcohols and liquid hydrocarbons could condense. Gaseous hydrocarbons were allowed to exit through a vent into a fume hood. These materials could be combusted in a modified burner. Gas samples were obtained from a sample port on the exit side of the condenser and analyzed via gas chromatography (GC).

EXAMPLE B

Pressure of 500 psi

540 grams of catalyst (64% MoS₂/18.4% CoS/17% K₂CO₃supported on crushed alumina beads) were placed in a one liter stainless steel high pressure reactor. The weight of the active component (MoS₂/CoS/K₂CO₃) of the catalyst was 100 grams. The premixed carbon monoxide and hydrogen gas (CO:H_2;2:1) was passed through the catalyst bed at 500 psi and 260° C. at a flow rate of 5 liters/min. The reaction products were passed through a condenser where alcohols and liquid hydrocarbons could condense. Gaseous hydrocarbons were allowed to exit a vent into a fume hood. Gas samples were obtained from a sample port on the exit side of the condenser and analyzed via gas chromatography.

EXAMPLE C

Pressure of 1150 psi

540 grams of catalyst (64% MoS₂/18.4% CoS/17% K₂CO₃supported on crushed alumina beads) were placed in a one liter stainless steel high pressure reactor as in Example B. The actual weight of the active component (MoS₂/CoS/K₂CO₃) of the catalyst was 100 grams. The premixed carbon monoxide and hydrogen gas (CO:H_2;2:1) was passed through the catalyst bed at 1150 psi and 260° C., at 5 liters/min. The reaction products were passed through a condenser where alcohols and liquid hydrocarbons could condense. Gaseous hydrocarbons were allowed to exit through a vent into a fume hood. Gas samples were obtained from a sample port on the exit side of the condenser and analyzed via gas chromatography.

EXAMPLE D

Pressure of 1500 psi

The catalyst in this experiment was the same as the catalyst in Example B and C. The premixed gas (CO:H₂1:2) was passed through the catalyst bed at 1500 psi and 260° C., at a flow rate of approximately 3 liters per minute. The reaction products were passed through a condenser where alcohols and liquid hydrocarbons could condense. Gaseous hydrocarbons were allowed to exit a vent into a fume hood. Gas samples were obtained from a sample port on the exit side of the condenser for analysis via gas chromatography.

EXAMPLE E

Pressure of 1500 psi

390 grams of catalyst (61% MoS₂/24.6% CoS/14% K₂CO₃supported on crushed alumina beads) were placed in a one liter stainless steel high pressure reactor. The actual weight of the active component (MoS₂/CoS/K₂CO₃) of the catalyst was 180 grams. The premixed carbon monoxide and hydrogen gas (CO:H_2;1:2) was passed through the catalyst bed at 1500 psi and 260° C., at a flow rate of 2.5 liters/min. The reaction products were passed through a condenser where alcohols and liquid hydrocarbons could condense. Gaseous hydrocarbons were allowed to exit a vent into a fume hood. Gas samples were collected from a gas sampling port prior to the gas entering the condenser and a sample from the sample port on the exit side of the condenser for analysis via gas chromatography.

EXAMPLE F

Pressure of 1500 psi

The catalyst was the same as the catalyst in Example E. The premixed gas (CO:H_2;1:2) was passed through the catalyst bed at 1500 psi and 260° C. at a flow rate of approximately 5 liters/min. The reaction products were passed through a condenser where alcohols and liquid hydrocarbons could condense. Gaseous hydrocarbons were allowed to exit trough a vent into a fume hood. Gas samples were collected from a gas sampling port prior to the gas entering the condenser and a sample from the sample port on the exit side of the condenser for analysis via gas chromatography.
TABLE 1
Summary of the Reaction Conditions
Flow
Ex- Catalyst Catalyst Temp. Pressure rate
periment type wt. (g) (° C.) (psi) CO:H2 (l/min)
A MoS₂/CoS/ 50 260 500 1:1 5
K₂CO₃
B MoS₂/CoS/ 100 260 500 2:1 5
K₂CO₃
C MoS₂/CoS/ 100 260 1000 2:1 5
K₂CO₃
D MoS₂/CoS/ 100 260 1500 1:2 3
K₂CO₃
E MoS₂/CoS/ 180 260 1500 1:2 2.5
K₂CO₃
F MoS₂/CoS/ 180 260 1500 1:2 5
K₂CO₃
For all of the experiments the reactants and products were analyzed by using a gas chromatograph equipped with a thermal conductivity detector (TCD) and a flame ionization detector (FID). Concentration of carbon monoxide and hydrogen were determined by the TCD detector and the alcohols and the hydrocarbons were analyzed via the FID detector.
Experiment A
50 grams of MoS₂/CoS/K₂CO₃catalyst at 260° C.,500 psi pressure and 1:1 CO:H₂molar feed ratio was used for the reaction carried out in Example A. A sample of the gas exiting from the condenser was obtained and analyzed via the GC. The analysis of the gas stream is presented in Tables 2, 3 and 4. About 1 gram of liquid was collected from the condenser. A sample of the liquid was analyzed by evaporation of the liquid in a gas bulb and then a gas sample out of the gas bulb was analyzed via the GC. The results are shown in table 2, 3 and 4. Mixed hydrocarbons and alcohols were found to be formed.
The GC data was used to calculate percent weights based on peak area ratios with the usual adjustments for the detector relative sensitivity to the different compounds. There was found about 1.63% weight ratio of the carbon monoxide and 0.03% of hydrogen were unreacted. This resulted in a high concentration of the hydrocarbons in the product. The initial starting composition 1:1 volume ratio is actually a 28:2 weight ratio (molecular weight ratio of equal moles of CO to H₂). The initial weight ratio was 14:1 and in later experiments the weight ratio was 54:1. The hydrogen has been used preferentially.
TABLE 2
Weight Ratios of Produced Alcohols Experiment A
Alcohols in the % wt. ratios in the % wt. ratios in the
Product liquid sample gas sample
Methanol 20 12
Ethanol 50 20
Propanol 30 23
Isopropanol N/D 45
Butanol N/D N/D
TABLE 3
Weight Ratios of Produced Hydrocarbons Experiment A
Hydrocarbons in the % wt. ratios in the % wt. ratios in
Product liquid sample the gas sample
Methane N/D 53
Ethane N/D 4
Ethylene N/D 27
Acetylene N/D 3
Propane N/D 10
Propylene N/D 3
TABLE 4
Weight Ratios of Unreacted Feed Stock Experiment A
% wt. ratios in the % wt. ratios in
Reactants liquid sample the gas sample
Hydrogen 0.00 1.8
Carbon Monoxide 0.00 98.2
The reaction was run at relatively low pressure, 500 psia. The catalyst showed reduced efficacy after several hours.
Experiment B
100 grams of MoS₂/CoS/K₂CO₃catalyst at 260° C., 500 psi pressure and 2:1 CO:H₂molar feed ratio were used for Experiment B. A sample of the gas exiting from the condenser was obtained and analyzed via the GC. The use of more catalyst (providing more reaction surface) and higher ratio of carbon monoxide to hydrogen yielded higher concentration of the higher alcohols in the product in comparison to the gas product from Experiment A. Results obtained are presented in Tables 5 through 7. The gas stream exiting the condenser was sampled for analysis of the produced alcohols. About equal molar ratio of carbon monoxide and hydrogen was left unreacted (Table 7). These conditions favored both the higher alcohols and the higher hydrocarbons.
TABLE 5
Weight Ratios of Produced Alcohols Experiment B
Alcohols in the % wt. ratios in the gas
product sample
Methanol 0.2
Ethanol 9.4
Propanol 30
Isopropanol 2.3
Butanol 54
tert-Butanol 4.7
TABLE 6
Weight Ratios of Produced Hydrocarbons Experiment B
Hydrocarbons in the % wt. ratios in the
product gas sample
Methane 20.6
Ethane 2
Ethylene 28.8
Acetylene 6.3
Propane 26
Propylene 16
TABLE 7
Weight Ratios of Unreacted Feedstock in the gas product Experiment B
% wt. ratios in the
Reactants gas sample
Hydrogen 43
Carbon Monoxide 57
This experiment was run also at 500 psia and exhibited the same retardation of efficacy as seen in Experiment .A
Experiment C
The same catalyst bed was used in this experiment as in Experiment B. The reaction was carried out at a higher pressure (1000 psi). The gas exiting from the condenser was sampled and analyzed via the GC. There were higher yields of hydrocarbons and a lower yield of alcohols when compared to Experiment B. The results from Experiment C are presented in Tables 8 through 10.
TABLE 8
Weight Ratios of Produced Alcohols Experiment C
Alcohols in the % wt. ratios in the gas
Product sample
Methanol
0
Ethanol 33.8
Propanol 26.9
Isopropanol 11.5
Butanol 27.8
tert-Butanol 0
TABLE 9
Weight Ratios of Produced Hydrocarbons Experiment C
Hydrocarbons in % wt. ratios in the gas
the product sample
Methane 31.2
Ethane 2.6
Ethylene 29
Acetylene 5.2
Propane 22.5
Propylene 9.3
TABLE 10
Weight Ratios of Unreacted Feedstock Experiment C
% wt. ratios in the
Reactants gas sample
Hydrogen 64
Carbon Monoxide 36
Experiment D
The catalyst bed from Experiments B and C was utilized. The reaction's pressure was 1500 psi with a 1:2 CO:H₂molar feed ratio. The gas exiting from the condenser was sampled and analyzed via the GC. Results for Experiment D are presented in Tables 11 through 13. Formation of alcohols (methanol and ethanol) only occurred with no hydrocarbon formation. In this experiment there was a higher yield of methanol than ethanol.
TABLE 11
Weight Ratios of Produced Alcohols Experiment D
Alcohols in the % wt. ratios in the
Product gas sample
Methanol 83
Ethanol 17
Propanol N/D
Isopropanol N/D
Butanol N/D
tert-Butanol N/D
TABLE 12
Weight Ratios of Produced Hydrocarbons Experiment D
Hydrocarbons in % wt. ratios in the
the product gas sample
Methane N/D
Ethane N/D
Ethylene N/D
Acetylene N/D
Propane N/D
Propylene N/D
TABLE 13
Weight Ratios of Unreacted Feedstock Experiment D
% wt. ratios in
Reactants the gas sample
Hydrogen 23
Carbon Monoxide 77
Experiment E
180 grams of MoS₂/CoS/K₂CO₃catalyst at 260° C., 1500 psi pressure and 1:2 CO:H₂molar feed ratio was used in Experiment E. Gas samples were collected after thecatalytic reactor6 and after thecondenser7. The samples were analyzed via the GC as previously. Results are presented in Tables 14 through 16.
TABLE 14
Weight Ratios of Produced Alcohols Experiment E
% wt. ratios in the % wt. ratios in the
Alcohols in the gas sample After gas sample After
Product the reactor the Condenser
Methanol 53.4 62
Ethanol 3.2 3
Propanol 14.3 14
Isopropanol 29.1 21
Butanol N/D N/D
TABLE 15
Weight ratios of Produced Hydrocarbons Experiment E
% wt. ratios in
% wt. ratios in the the gas sample
Hydrocarbons in the gas sample After After the
Product the Reactor Condenser
Methane 87.1 91.8
Ethane 0.01 0.3
Ethylene 0.6 1.3
Acetylene 0.7 3.4
Propane 0.35 1.3
Propylene 0.1 1.4
TABLE 16
Weight Ratios of Unreacted Feedstock Experiment E
% wt. ratios in the % wt. ratios in the
gas sample After gas sample After
Reactants Reactor the Condenser
Hydrogen 69.2 95
Carbon Monoxide 30.7 5
Experiment F
The reaction conditions for Experiment F were 180 grams of MoS₂/CoS/K₂CO₃catalyst at 260° C., 1500 psi pressure and 1:2 CO:H₂molar feed ratio. Gas samples were collected after thecatalytic reactor6 and after thecondenser7. Both samples were analyzed via the GC. Results are presented in Tables 17 through 19.
TABLE17
Weight Ratios of Produced Alcohols Experiment F
% wt. ratios in the % wt. ratios in the
Alcohols in the gas sample After gas sample After
Product the Reactor the Condenser
Methanol 100 72
Ethanol N/D 20
Propanol N/D 4
Isopropanol N/D 4
Butanol N/D N/D
TABLE 18
Weight Ratios of Produced Hydrocarbons Experiment F
% wt. ratios in
% wt. ratios in the the gas sample
Hydrocarbons in the gas sample After After the
Product the Reactor Condenser
Methane 96.0 93.5
Ethane 0.2 0.4
Ethylene 1.0 1.4
Acetylene 0.8 1.4
Propane 0.4 0.7
Propylene 1.6 2.5
TABLE 19
Weight Ratios of Unreacted Feedstock Experiment F
% wt. ratios in
% wt. ratios in the the gas sample
gas sample After After the
Reactants the Reactor Condenser
Hydrogen 43.4 27
Carbon Monoxide 56.6 73
For the formation of alcohols it was found that high pressure was important to obtain the required concentrations. Pressures below 1500 psi resulted in the formation of hydrocarbons. Unexpectedly it was found that the reaction catalyzed by MoS₂/K₂CO₃was more effective in the formation of longer chain alcohols as compared to the MoS₂/CoS/K₂CO₃catalyst that made more methanol.
It was discovered that the specific catalyst ratios used in these experiments are critical to produce the desired mixed alcohol stream that has the highest concentration of ethanol. The ratio was between 61-64% MoS₂, 18.4-24.6% CoS₂and 14-17% K₂CO₃. Surprisingly a reduction in CoS₂favored longer chain length alcohols.

Claims

1. An energy self sufficient process for the production of mixed alcohols from components of municipal solid waste, which comprises:

gasifying combustible portions of municipal solid waste producing a synthesis gas having CO and hydrogen at temperature at around or above 700° C.;

sending portion of said synthesis gas to a boiler or a turbine wherein excess electricity and heat produced operates process equipment;

sending remainder of said synthesis gas to a gas conditioning system reducing temperature and increasing the pressure of said synthesis gas;

sending the synthesis gas from said gas conditioning system to a catalytic conversion system producing said mixed alcohols;

sending unconverted (excess/unused/unneeded) synthesis gas back to said boiler or said turbine;

condensing product fluid from said catalytic conversion system; and

separating said mixed alcohols from hydrocarbons and other combustible liquids wherein waste liquids from condensing step are regasified.

2. The process ofclaim 1 further comprising maintaining supercritical pressure for the synthesis gas reaction mixture within the catalytic conversion system.

3. The process ofclaim 1 further comprising maintaining supercritical temperature for the synthesis gas reaction mixture within the catalytic conversion system.

4. The process ofclaim 2 further comprising:

monitoring the gas and liquid compositions from the catalytic reactor; and

adjusting the pressure to maintain a supercritical state.

5. The process ofclaim 3 comprising:

monitoring the gas and liquid compositions from the catalytic reactor; and

adjusting the temperature to maintain a supercritical state.

6. An energy self sufficient process for the production of mixed alcohols and pipeline quality natural gas from components of municipal solid waste, which comprises: gasifying combustible portions of municipal solid waste producing a synthesis gas having methane, lower hydrocarbons, CO and hydrogen at temperature at around or above 700° C.;

sending residual from alcohol producing unit to a gas conditioning system to produce pipeline quality gas; and

condensing product fluid from said catalytic conversion system.

7. The process ofclaim 6 further comprising maintaining supercritical pressure for the synthesis gas reaction mixture within the catalytic conversion system.

8. The process ofclaim 6 further comprising maintaining supercritical temperature for the synthesis gas reaction mixture within the catalytic conversion system.

9. The process ofclaim 7 further comprising:

monitoring the gas and liquid compositions from the catalytic reactor; and

adjusting the pressure to maintain a supercritical state.

10. The process ofclaim 8 comprising:

monitoring the gas and liquid compositions from the catalytic reactor; and

adjusting the temperature to maintain a supercritical state.