PARTICULATE COMPOSITION
Rodney M. wise James M. ~ander Meer Background 1. Field of the Invention The presQnt invention relates to compositions of matter which are useful for water softening or as detergent builders.
2. Description of the Art Aluminosilicates which have high calcium and magnesium exchang-rates and capacity have been added to water softening and detergentproducts to remove water hardness. Effective removal of calcium and magnesium ions from water when considered in the context of detergent products is important in that those ions can precipitate anionic sur-factants rendering the former less effective in fabric cleaning.
Moreover, if the calcium and magnesium ions are not removed from water used for washing, these ions will interact with soils on the fabrics thus interfering with soil removal.
U.S. Patent 3,985,669, issued October 12, 197~, Krummel et al, describes the formulation of a detergent composition containing aluminosilicates and alkali metal silicates. In Krummel et al the silicates are present at a very low level to avoid the interaction with the aluminosilicate. This product is formed by spray drying all of the components in the composition including the aluminosilicate and the alkali metal silicate.
It has been found that the incorporation of the aluminosilicate materials into detergent and water softening compositions described above presents great difficulties. For instance, if aluminosilicates are to be admixed into the composition as a dry material, a consid-3Q erable quantity of dust can be generated by improper handling of thefinely divided aluminosilicate. Moreover, the a]uminosilicates per se are not free flowing. It is also noted that if tne aluminosilicate materials with which the present invention is concerned are admixed dry with the remainder of a comoosition, that segregation of the fine aluminosilicate materi31s will occur during packing and transportation of tne finished product. The segregatlon is extremely undesirable in tnat when the consumer uses the product the lack of uniformity m~y result in over-usage or under-usage.
-, ~, ,.,~, ~60135 The przsent invention is an improv-ment nn U.S. ~atent ~,n96,081 Pnenicie et al, issued ~unP 20, 1978.
~This patent teaches-agglomeration of the aluminosilicate p~r-ticles using an organic agglomerating agent and an inorganic salt.
This agglomerate can be admixed with conventional spray-dried deter-gent granules.
Throughout the specification and claims~ percentages and ratios are by weight and ternperatures are in degrees centigrade unless other-wise indicated.
Summary of the Invention Ihe present mvelltion provides a free-flowmg particulate water softening c~nposition c~npris~ng an int~mate m~xture of:
(a) from about 60% to about 95% of an aluminosilicate detergency builder, preferably (i) an amorphous aluminosilicate;
(ii) a hydrated crystalline zeolite selected from the group consisting of Zeolite A, X, and P having a particle size of from about 0.1 to about 25 microns; and ~ (iii)mixtures thereof having a calcium ion exchange capacity of at least about 200 mg eq./g (four milliequiva-lents/g.); and a calcium ion exchange rate of at least about 2 grains/gallon/minute gram;
(b) from about 1% to about 4% of synthetic anionic detergent I surfactants which are relatively hardness insensitive;
(c) from about 1% to about 10% of an inorganic salt and being essentially free of silicates; and (d) ~alance water.
Detailed Description of the Invention I The aluminosilicate detergency builders of this invention comprise both amorphous and crystalline aluminosilicates as is well known in the art. U.S. Patent 4,096,081 contains a description of such I builders. Zeolites A, X and P are preferred, with Zeolite A being most preferred.
An essential feature of the ion exch~nge builder materials herein is that they be in a hydrated form, i.e., contain at least about 10%
by weight of water. Highly preferred Zeolite A aluminosilicates herein contain the theoretical maximum of from about 18~ to about 22%
. . .
'wt.) wa~er in their crystal matrix It has ~eell f`sJndJ fnr example;
that less highly hydrated Zeolite A aluminosilicates, e.g., those with about 6% water, do not function effectively as ion exchange builders when employed in the context of a laundry detergent composition.
A second essential feature of the ion exchange builder materials herein is their particle size range. ûf course, the amorphous aluminosilicates inherently have a small particle size (ca. û.ûl micron - 5 micron diameter). However, the crystalline aluminosili-cates must have a small particle size in the range disclosed herein.
Proper selection of small particle sizes results in fast, highly efficient builder materials. Moreover, the small particle size of the preferred aluminosilicates herein (C10 microns) presumably accounts for the fact that they are not noticeably deposited on fabrics from an aqueous laundering liquor. This nondeposition is, of course, desir-able when the aluminosilicates are employed as deter~ent builders.
The amorphous aluminosilicate ion exchange builder/water softening materials herein can be prepared according to the following procedure:
(a) Admix sodium aluminate (NaA102) and sodium hydroxide in water to form a mixture havin~ the fnllo~Ying (preferred) 2Q weight ratios of the components:
H20/NaA102 = 2.9:1 H20/NaOH = 5.2:1 NaA102/NaOH = 1.8:1.
The temperature of the mixture is adjusted to about 20C-70C, preferably about 50C. If prepared at lower temperatures, the mixture of aluminate and sodium hydroxide is not a true solution and may contain a small quantity of finely dispersed particulate materials.
(D) Add a sodium silicate solution (ca. 37% wt. solid; 3.2:1 SiO2/Na20 ratio) rapidly to the mixture of step (a).
This rapid mixing step can be carried out using a vessel employed ~ith an efficient agitator; alternatively, the two mixtures at the desired temperature can be metered into an inline mixer ~.~hich can be part of a dominanc bath system to provide a continuous process. The ratio of NaA102 to sodium silicate (anhydrous basis) is about l.~:l.
(c) Heat the mixtlJre of ster ¢b) rapid~y to 7SC to 95C
(preferably 80C - 85C) and maintain at this temperature for 10 minutes to 60 minutes tpreferably 10 minutes - 20 minutes).
(d) Cool the slurry from step (c) to about 50C and filter.
Recover the resulting filter ca~e and wash in water using a sufficient quantity of water to yield a wash water/solids (anhydrous basis) weight ratio of about 2.û:1 (preferred).
Repeat the filtration and washing operations.
The filter cake prepared by the foregoing prûcess comprises a mixture of crystallinelaluminosilicate and amorphous aluminosilicate in approximately a 1:1 ~wt.) ratio. The material from the filter cake exhibits a rapid and efficient uptake o-f both Ca+~ and Mg++ ions.
The filter cake is useful per se as an ion exchange material. For use in powdered or granular detergent compositions, it is preferred to dry the filter cake only the minimum amount to eliminate free moisture, using a drying temperature below about 175C to avoid excessive dehydration. Preferably, the drying is performed at lOûC to lû5C.
The amorphous aluminosilicate of this invention can, if desired be separated from the amorphous-crystalline mixture prepared in the foregoing manner by simply suspending the filter cake mixture in water. When thus suspended, the crystalllne portion of the mix settles out (over a period of about 1-6 hours), whereas the amorphous material remains suspended in the aqueous medium. The amorphous material can be separated by decantation or other physical means. Of course, low speed centrifugation can be employed to more rapidly separate the amorphous c~mponent from the crystalline component of the mixtures herein. I
Both the crystalline and amorphous aluminosilicate ion exchangers herein are further characterized by their calcium ion exchange capac-ity which is preferably at least about 20û mg. equivalent of CaC03 hardness/gram of aluminosilicate, calculated on an anhydrous basis, and ~hich preferably lies ~ithin the range of about 3no mg. eq./g. to about 352 mg. eq./g.
The ion exchange materials herein are further characterized by their calcium ion exchange rate which is at least about 2 grains
3~i .
(Ca++)/gal./min~/g. of alumincsilicatr (3nh~Jd~ous basls~. Optimum aluminosilicates for builder purposes exhibit a Ca++ exchange rate of at least about 4 gr./gal.~min./g.
The amorphous aluminosilicate ion exchanges herein are further characterized by their magnesium exchange capacity, which is at least about 50 mg. eq. of CaCû3 hardness/gram of aluminosilicate, calcu-lated on an anhydrous basis, and which generally lies within the range of about 5û mg. eq./g. to 15û mg. eq./g. or greater.
The amorphous ion exchange materials herein are still further characterized by their magnesium ion exchange rate which is at least about 1 grain (Mg++)/gal./min./g. of aluminosilicate (anhydrous basiâ). Optimum aluminosilicates for builder purposes exhibit a magnesium exchange rate of at least about 2 gr./gal./min./g.
The ion exchange properties of the aluminosilicates herein can conveniently be determined by means of a calcium ion electrode and a divalent ion el~ctrode. In this technique the rate and capacity of Ca++ and Mg++ uptake from an aqueous solution containing a kno~n quantity of Ca++ and Mg~+ ions are determined as a function of the amount of aluminosilicate ion exchange material added to the solu-tion. More specifically, the ion exchange rates of the amorphous andmixed amorphous-crystalline aluminosilicates herein are determined as follo~s. The aluminosilicate prepared in the foregoing manner is added in the sodium form to 15û ml. of aqueous solution containing 4.7 gr./gal. Ca~+ and 2.4 gr./gal. Mg++ (measured as CaC03) at a concentration of 0.05% (wt.), pH of 10.0, and with gentle stirring of the solution. The rate of calcium depletion is measured using the calcium electrode (commercially available; "Orion)" and the rate of total calcium and magnesium depletion iâ determined using the general divalent cation electrode. Magnesium lon removal is thereafter deter-mined by the difference in readings. The rate of depletion is deter-mined for each cation by taking measurements at appropriate time intervals. Total depletion from the solution is calculated after ten minutes, which corresponds to the normal wash time in an aqueous laundering process. Rate curves for calcium depletion, magnesium depletion and mixed calcium and magnesium deplrtioll can be plotted as gr./gal. v. time.
* Trademark i Q~3S
Calcium exchange capacity of the aluminnsi]icates herein car; be determined by a simple titration method. In practice the alumino-silicate sample is equilibrated with a known excess of Ca++. After equilibration and uptake of the calcium ion, the excess calcium ion remaining in solution is determined by a standard titration with EDTA, using a standard Eriochrome Black T Indicator. Magnesium ion capacity is determined titrimetrically, in similar fashion.
As noted hereinabove, both the crystalline and amorphous alumino-silicates herein exhibit excellent rates of exchange and capacities for calcium ions. Moreover, the amorphous material herein addition-ally provides rapid and efficient uptake of magnesium ions. Accord-ingly, a mixture of crystalline and amorphous material can provide mixed Ca++/Mg++ hardness control.
Preferably, the compositions of this invention are essentially free of the organic agglomerating agents of U.S. Patent 4,û96,081.
The surfactant agglomerating agents of this invention include the following.
Preferably the detergent component of the present invention is a water-soluble salt of: an ethoxylated sulfated alcohol with an average degree of ethoxylation of about l to about lO and an alkyl chain length of from about 8 to about 2û; an alkyl benzene sulfonate with an average alkyl chain length between about 9 and about 15, pre-ferably from about 11 to about 13, and most preferably about 11.8 carbon atoms; a C6-C20 alpha-sulfocarboxylic acid or ester thereof having l to 14 carbon atoms in the alcohol radical; a C8-Cl8 secondary paraffin sulfonate; a ClO-Cl8 olefin sulfonate or mix-tures thereof; or other hardness insensitive anionic surfactant.
Such preferred detergents are discussed below. Blends of surfactants which exhibit hardness resistance (insensitivity) can be used as well.
An especially preferred alkyl ether sulfate detergent component of the present invention is a mixture of alkyl ether sulfates, said mix-ture having an average (arithmetic mean) carhon chain length within the range of about 12 to 16 carbon atoms~ preferably from about 14 to 15 carbon atoms7 and an average (arithmetic me3n) degree of ethoxy-lation of from about l to 4 moles of ethylene oxide, Dreferably from a~out 2 to 3 moles of ethylene oxide.
~1~135 Specifically, such preferred mix~res comprise rom about 0 tO 10%
by weight of mixture of Cl2 13 compounds, from about 50 to 100% by weight of mixture of Cl4 15 compounds, and from about 0 to 45% by weight of mixture of Cl6 17 compounds, and from about 0 to 10% by S weight of a mixture of Cl8 19 compounds. further, such preferred alkyl ether sulfate mixtures comprise from about 0 to 30~ by weight of mixture of compounds having a degree of ethoxylation of 0, from about 45 to 95% by weight of mixture of compounds having a degree of ethoxy-lation from l to 4, from about 5 to 25% by weight of mixture of com-pounds having a degree of ethoxylation from 5 to 8, and from about 0to 15% by weight of mixture of compounds having a degree of ethoxy-lation greater than 8. The sulfated condensation products of ethoxy-lated alcohols of 8 to 24 alkyl carbons and with from l to 30, prefer-a~ly l to 4 moles of ethylene oxide may be used in place of the pre-ferred alkyl ether sulfates discussed above.
Preferred water-soluble organic detergent compounds herein also include alkyl benzene sulfonates (preferably essentially linear, although "hard" ABS may be used) containing from about 9 to 15 carbon atoms in the alkyl group. Examples of the above are sodium and potas-sium alkyl benzene sulfonates in which the alkyl group contains fromabout ll to about l~ carbon atoms, in straight chain or branched chain configuration, e.g., those of the type described in U.S. Pat. Nos.
2,220,099 and 2,477,383. Especially valuable are straight chain alkyl benzene sulfonates in which the average of the alkyl groups is about 11.8 carbon atoms, abbreviated as Cll 8LAS.
Another useful detergent compound herein includes the water-sol-uble salts of esters of alpha-sulfonated fatty 3cids containing from about 6 to 20 carbon atoms in the fatty acid group and their esters with alcohols containing from about l to 14, preferably l to 2, carbon atoms.
Preferred "olefin sulfonate" detergent mixtures utilizable herein comprise olefin sulfonates containing from lO to about 18 carbon atoms. Such materials can be produced by sulfonation of olefins by means of uncomplexed sulfur trioxide followed by neutralization under conditions such that any sultones present are hydrolyzed to the corre-sponding hydroxy-alkane sulfonates. The alpha-olefin starting mater~
ials preferably have from 14 to 16 carbon atoms. Said preferred alpha-olefin sulfonates are descri~e~ in U.S. Pat~ ~o. 3,3}2,880, Kessler et al, issued July 25, 1967.
The secondary paraffin sulfonates embraced in the present inven-tion are essentially linear and contain from a~out 8 to about 18 carbon atoms, preferably from about 12 to about 16 and more preferably from about 14 to about 15 carbon atoms in the alkyl radical.
Other anionic detergent compounds herein include the sodium alkyl glyceryl ether sulfates, especially those ethers of higher alcohols derived from tallow and coconut oil; sodium coconut oil fatty acid monoglyceride sulfonates and sulfates; and sodium or potassium salts of alkyl ph~nol ethylene oxide ether sulfate containing about 1 to about 10 units of ethylene oxide per molecule and wherein the alkyl groups contain about 8 to about 12 carbon atoms.
Other useful detergents include water-soluble salts of 2-acyl-oxy-alkane-l-sulfonic acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 18 carbon atoms in the alkane moiety; beta-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 18 carbon atoms in the alkane moiety; alkylmethylammoniopropane sulfonates and alkylmethylammoniohydroxypropane sulfonates wherein the a~kyllgroup in both types contains from about 14 to 18 carbon atoms; and all~yl glyc-erol ether sulfates with from lû to 18 carbon atoms in the alkyl radical.
A typical listing of the classes and species of deterglent com-pounds useful herein appear in U.S. Pat. No. 3~852~211~ to Ohren issued D~c. 3 ~ 1974~ ~he foregoing list of detergent compounds and mixtures which can be used in the instant compositions is representative of such materials, but is not intended to be limiting.
The compositions comprise from about 1 to about 4%, preferably from about 2~o to about 3% of hardness insensitive anionic surfactant.
Higher levels of surfactant simply dilute the zeolite without any benefit and can give undesirable physical pro~erties to the agglom-erate.
The surfactant improves dispersion of the zeolite as sho~Yn herein-after thus minimizing unacceptable deposits, e.g. on fabrics, and increasing the rate of ion exchange.
.~ .
~ 35 The inorganic salts are water soiu~le anc form lons. They promote dispersion of the aluminosilicate as shown to rapidly control the water hardness. Examples of such inorganic salts include those having alkali metal cations such as sodium, or potassium, and having as ani-ons thereof sulfates, chlorides, carbonates, bicarbonates, alumin-ates and phosphates, and mixtures thereof.
Preferred inorganic salts include sodium 'sulfate, sodium carbon-ate, sodium orthophosphate, sodium pyrophosphate, sodium tripolyphos-phate, and sodium hexametaphosphate. Especially preferred are sodium sulfate and sodium carbonate. Alkali metal silicates should not be' present because of their ability to polymerize the aluminosilicate leading to deposits upon washed fabrics.
When the aluminosilicate, the inorganic salt and the organic sur-factant are to be incorporated into a detergent composition, addition-al surface active agent (detergent surfactant) will be included as a portion of the overall detergent co~position since the level of sur-factant herein is insufficient to form a complete detergent product.
Exemplary of detergent components which may bo used in the present invention are those described in U.S. Patent ~,852,~11 to ûhren, issued December 3, 1974~
Composition Preparation The preparation of the particulate containing the aluminosilicate, the inorganic salt and the detergent surfactant is described as follows:
(a) dispersing the detergent surfactant;
(b) dispersing the inorganic salt into the detergent surfactant;
(c) admixing into the dispersed detergent surfactant the alumino-silicate of the present invention, thereby forming an inti-mate mixture; and, (d) solidifying the resultant mass to form the particulate.
Alternatively, the detergent surfactant can be sprayed onto a bed of the aluminosilicate and the inorganic salt. Water may be added to the mixture of the detergent surfactant, the inorganic salt, and the aluminosilicate to facilitate mixing. The excess water is then driven off by heating on forming the particulate.
.~
In a preferred method, suifurlc a~id is atided to the synthesis liquor of the aluminosilicate to neutralize excess c3ustic (while staying above pH 9) and form Na2S04. The surfactant is then dis-persed in the slurry and the product is spray or flash dried.
AnothQr preferred method of preparing the particulate of the present invention is to spray the mixture of the aluminosilicate, the inorganic salt and the detergent surfactant to form granules of the size compatible with normal detergent particles. It is to be under-stood, however, that the product can take several forms, e.g. cakes, flakes, prills, or granules which are reduced by conventional methods to the appropriate size.
The préferred method of preparing the particulate of the present invention is by spray-drying or spray cooling the mass to form the particulate. It is essential when spray-drying is employed that the 15 aluminosilicate should not be dehydrated beyond the point where its ion exchange capacity is adversely affected. Also, certain of the surfactants which are hea-t sensitive should not be heated to the extent at which they beyin to decompose.
When a spray-drying operation is used to prepare the agglomerate 20 the apparatus for conducting the drying operating may be a multilevel spray-drying tower such as that describe:l in U.S. Patents3,629, 951 and 3,629,955 issued to Davis et al on December 28, 1971.
In preparing the particulate of the present invention the deter-25 gent surfactant will be present at from about 1/2% to about 4%, pre-ferably from about 1-1~2% to about 2-1/2% by weight while the alumino-silicate will be present at from about 60% to about 95%, preferably from about 70% to about 80~ by weight.
The inorganic salts which promote lessened friability are used at 30 a level of from about 1/2% to about 10%, preferably from about 2% to about 4%. Larger amounts of the inorganic salts may be utilized in the particulate, however, the benefit reaches a maximum at about 5%
and additional amounts merely take up more formula room.
Composition Utilization When the particulate of the present invention is utilized as a water softener for laundering purposes, it is simply added to the wash s tub or washing machine, preferably before the fabrics and the deter-gent composition are introduced and after the water has been intro-duced into the container.
When the particulate of the present invention is used as part of a complete detergent product admixed with a separate granule containing additional detergent surfactant, the overall product is desirably added to the wash tuo or the washing machine before the fabrics and after the water has been added.
The amount of the particulate utilized as a water softening pre-lû treatment is simply an amount sufficient to remove most of the calciumand magnesium ions present in the wash water. As the product of the present invention normally has a density of from about 0.45 gram per cc to about 0.65 gram per cc, sufficient usage of the product will, under most United States conditions, be satisfied by the use of from about 1/4 cup to about 1 cup. Under continental European washing conditions where the water hardness is somewhat greater, the product will normally be used at a level of from about 1/2 cup to about 3 cups .
Laundry detergent products of the present invention as used under U.S. washing conditions at from about 1/2 to about 1-1/2 cups and from about 1 cup to about 3 cups under European washing conditions.
The agglomerate of this invention, when added to a spray-dried detergent granule containing a surfactant to give an agglomerate level of from about 5~ to about 80%, preferably from about 10,~ to about 6û%
by weight of the total composition, provides a complete detergent composition with little or no apparent formation of insolubles. This is especially important when the spray-dried detergent granule con-tains large amounts of sillcates. In order to avoid segregation, the agglomerate should have a size that is compatible with the detergent granule, e.g., not less than about 100 microns in diameter, preferably not less than about 150 microns in diameter. The agglomerates of this invention do not break down unacceptably under ordinary handling and shipping.
Par-ticle size can be adjusted by sieving and recycling or by adjusting spray drying pressure and nozzle size.
Preferably th~ agg~omerates of this invention are compl~tely free of the agglumerating compounds of U.S. Patent 4,095,081, and espe-cially free of the polyethylene glycol of said patent.
The following are Examples of the present invention:
EXAMPLE I
Detergent compositions were made with the intent of increasing the thoroughness of zeolite builder dispersion in wash water. The expec-ted benefits of increased dispersion are (1) reduced incidence of insoluble aggregates on washed fabrics, and (2) increased rate of zeolite availability for complexation of water hardness.
The method used for evaluating degree of dispersion involved Nephelometer Turbidity Unit (NTU) measuremqnts of wash water concen-trations (0.3 9. active zeolite/l. city water at about 9 grains/gallon hardness). A water sample was grabbed after four minutes of normal wash agitation with the zeolite-containing composition present. A
higher turbidity reading indicates greater exposed particle surface and thus more effective dispersion. A more sustained turbidity reading after 30 minutes of static observation indicates a slower settling rate and thus a smaller average~zeolite aggregate size.
Zeolite A,"Arogen 200a~ from Huber Co., was used in these experiments.
Turbidity, NTU
Initial 30 Min.
Composition Reading Static Reading A. Zeolite, as received 80 40 B. Zeolite in currently commer- 175 98 cial detergent product C. Zeolite + sodium sulfate 110 60 D. Zeolite + Na2SO ~ poly- 165 1 90 ethylene g~yco~ (M.W.
8000) (PEG) E. Zeolite + Na2504 + PEG + 255 200 2?~ sulfate F. Zeolite + Na2S04 + 280 250 21~ sul~ate * Trademark . ..
~L~G~135 G. Zeolite + Na2S04 + PEG 220 165 sodium Cll alkyl benzene sul~onate (C11.8 LAS) H. Zeolite + Na2S04 ~ 280 190 C11.8 LAS
It is known that electrolytes alone aid in dispersion of alumino-silicates in an aqueous medium, and this is seen in comparing A and C. The addition of a binding and wettiny agent, polyethylene glycol (PEG 80ûO), in D (ref. Patent 4,096,081) improves dispersibility to the level seen with a typical full detergent composition (non-phos-phate), as in B. Addition of a relatively hardness-insensitlve syn-thetic surfactant in E and G improves the dispersion, though removal of the PEG (F and H) now shows further benefit in fineness and stabil-ity of the zeolite dispersion.
Both of the surfactants in E-H are acceptably hardness insensi-tive. A tallow alkyl sulfate, for example "Yould be precipitated by free hardness and rendered ineffective as a zeolite dispersant. It is noted that the higher sustained dispersion at 3û minutes with samples E and F reflect the greater degree of hardness insensitivity of the alkyl polyethoxy sulfate vs. the alkylbenzene sulfonate of G and H.
In all cases, the zeolite was dried from an aqueous slurry of about 5û-60% total water to which the other ingredients had been added. I
The slurry was heated to about 140F and mix~d thoroughly. This mixture was then dried in a thin film in a 7dc oven until only about 18-20~ H2û remained. The water of hydration in the Zeolite A
is generally not removed under these conditions. The dried cake was granulated and screened through a 14 mesh Tyler sc~een. The resultant density was about 0.58 g./cc. The particle size was mostly greater than about 150 microns. Zeolite delivered to tne wash water was con-trolled at 0.3 9/1. and other components (except in a) were used as:
sodium sulfate at 0.01 to 0.03 9./l., PEG 8000 at 0.01 to 0.015 9./1., and synthetic surfactants at 0.008 9./1.
EXAMPLE II
A base granule was syray dried containing:
Percentage Sodium Cll 8 alkyl benzene sulfonate4.76 Sodilumf tC14 16 alkyl polyethoxylate 1 o 11.48 Sodium tallow alkyl sulfa-te 3.36 Sodium silicate (2.0r) 8.4 Sodium carbonate 18.2 Sodium sulfate 47.3 Trisodium sulfosuccinate 2.8 Water and minors Balance 27.6% of the following admix, formed by spray drying a slurry according to Example lH, heated to about 175F and pressure atomized lS into a pilot scale (10' diameter) spray-drying tower with 500F
inlet air, was mixed with the above base granule and the mixture was sprayed with .9% polyethyleneglycol (M.W. 8ûûO) and 0.14% perfume The admix density was about 0.55-û.58 g./cc. and the particle size was about 9W0 greater than 15û micron diameter.
Admix composition:
Zeolite A (dry basis) 72.5%
Cll 8 linear alkylbenzene ~.û~
sulfonate, sodium salt Sodium sulfate 7.5%
Water 18.0%
Total 100.0%
EXAMPLE III (comparison) Composition of Example II was made using powdered zeolite (as received) admixed to the base granule composition. The resulting detergent product was excessively dusty and free flo~Y was unacceptable due to bridging and surging. Segregation is a further potential prob-lem with this approach.
EX~MPLE I~
The zeolite composition of Example II is metereà into a fluidized bed along with other dry ingredients and nonionic surfactant, minors, and perfume are sprayed on.
Comoosition: .
-Zeolite composition from Example II 35~
Ethoxylated nonionic (C12 13 E6 5) 15%
Sodium tripolyphosphate~ granular 25%
Sodium carbonate, granular 10%
Sodium sulfate, granular 14%
Water, colorants, perfume, brighteners 1%
lOû%