CA2113413A1

CA2113413A1 - Process for producing a detergent composition containing alkyl sulfate particles and base granules

Info

Publication number: CA2113413A1
Application number: CA 2113413
Authority: CA
Inventors: George J. Kaminsky; Frank J. Mueller
Original assignee: Individual
Current assignee: Procter and Gamble Co
Priority date: 1991-07-15
Filing date: 1992-07-06
Publication date: 1993-02-04
Also published as: JPH07500125A; CN1070222A; EP0594688A1; MX9204154A; CZ9594A3; FI940189A; FI940189A0; HU9400115D0; IE922296A1; TW216444B; WO1993002168A1; SK4494A3; MA22590A1; AU2309892A

Abstract

This relates to a process for the production of a granular detergent composition comprising admixed high active alkyl sulfate particles made by steps including continuous neutralization, and spray dried granules comprising detergency builder, soluble silicate, and essentially no alkyl sulfate.

Description

WO 93/02168 r 1 1 3 4 1 3 lusg2/0s6sg PROCESS FOR PRODUCING A DETER6ENT COMPOSITION CONTAINING AL~YL
SULFATE PARTICLES AND BASE ~RANULES

fIELD OF THE INYENTION
The present invention relates to a process for preparing granular detergent compositions by separately prepar~ng spray dried base granules and alkyl sulfa~e parttcles~ and then admixing them.

The traditional ~ethod hr productng detergent granules is spray dry~ng. Typically detergent ingredients such as surfactant builder sillcate and carbonate are ~ixed in a tank to for~ a slurry which ts about 35% to 50% water. This slurry is then ato~tzed 1n a spray dry1ng tower to reduce ~oisture. It is poss1ble to compact spray dried particles to ~ake dense detergent gr _ les. See U.S. Patent 4 7lS 97g Hoore et al. issued Oe:~ber 29 1987. However spray drying ~ethods generally ~ 0volve a 1tmited a~ount (less than 40X) of organic co~ponents; such as surfactant for environ~ental and safety reasons.
;~ An ~lternative ~ethod for ~ak1ng detergent particles is by eont~nuous neutrallzation in for exa~ple ~ a continuous neutral1zation loop follo~ed by particle for~ation. Copending U.S. Patent Application Ser1al No. 647 338 Mueller et al filep January 28 l9gl wh~ch is a cont~nuation-in-part of Serial No.
364~721 filed June 9 1989 describes the formation of high actlve (>50% act~ve) detergent granules using a cont~nuous neutral1zation system followed by part~cle fonmat~on.
Polyethylene glycol and/or certaln ethoxylated nonionic sur~actants are added dur1ng neutral1zatiQn of alkyl sulfur1c and/or al bl benzene sulfonic ac~ds w1th concentrated sodium hydroxide (~ about 62X). The process and parttcles made by the process are 1ncluded. Th~s case published as EP 90 306 139.8 on December 12 l990.
Copending U.S. P~tent Application Serial No. 552 663 ~; Ofosu-~ ante et al f~led July 16 l990 (allowed~ describes a ~ process for produc1ng ~high active detergent partt~les wh~ch ,,; .
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SUBSTITUTE SHEET

2~13~13 ~' 93/0216~ PCI`/US92/056S9 includes reacting ~n a cont~nuous neutrallzation system the acid form of an anionic surfactant w~th alkal~ metal hydroxide and add~ng to the neutral~za~ion system during h rmation of the neutralized product an ~-aminodicarboxyllc acid selected from the group cons~st1ng of gluta~ic ac1d, aspart1c acid, amino~alon1e actd, a~tnoad~p~c actd, and 2-a~no-2^~ethylpentanedto1c acid, or their alkali mætal salts. H~gh actlve detergent part~cles are tncluded.
Copending U.S. Patent Applicatlon Ser~al No. 288,759, Strauss lo et al, f11ed Dece~ber 22, 1988 (allowed), describes a process for ~; ~ prepartng concentrated surfactant granules fro~ a h19h act~ve surfactant paste us~ng M ne d1spersion cold granulat~on. Th1s publ~shed as EP 89 306 335~4 on January 3, 1990.
U.S. Patent ~,534,8~9, Idtng et al, issued August 13, 1985, dtscloses a process for ~ak1ng t~proved synthetic surfactant akes from a roll dru~ drled paste containing sodlum alkyl sulfate, sodium alkylbenzene sulfonate, and water-soluble ~norganic salts. The hot flakes are cooled in a low Eoisture envtronment having a low dew po~nt.
o None of the above d~sclose the tnstant process for producing a granular detergent compos1t10n by adm~xing high active alkyl - sulfate part~cles wtth spray dried base granules containing little.
to no alkyl sulfate, nor to they disclose a co~posit~on compris1ng partlcles with high levels of alkyl sulfate, and C10 16 l~near ~5 alkylbenzane sulfonate and/or C12_1g soap, along with granules containing detergency bu~lder and soluble s~licate, which are essentially free of alkyl sulfate.
SUMMARY OF T~E INVENTION
The preseht invent~on relates to a process for the protuct10n of a granular detergent compos~t~on, compr~stng:
(a) spray drying a slurry comprising, by weight of the spray dr~ed granules: less than about 2~ of alkyl sulfate;
from O to about 40Z of an~onic surfactant other than ~nDg3/02168 P~:r/us92/o56s9 - 3 - ~ 1 ~ 3 ~ 1 3 atkyl sulfate; from about 10 to 80X of detergency butlder; and fro~ about 1 to 15% of soluble slltcate;
(b) produc1ng alkyl sulfate parttcles by steps co~pris~ng ;~
cont~nuous htgh acttve neutral~zatton, satd particles , ~ co~prtsing, by weight of the alkyl sulfate part~cles:
fro~ about 60 to 99X Of Cl2~l8 alkrl sulfat~ ethoxylated wlth fro~ O to about 4 ~oles of ethylene ox~de per mole o~ alkyl sulfate; and -(c) ~ad~1xtng sa1d spray drled granules wlth sa~d alkyl ~ sulfate parttcles, respectlvely, ~n a ratto between about lO:9O and 99~
OESCR~PTION OF THE INVENTION
As an effort ~ntt1allr to reduce plu~e e~ission fro~ the spray dry1ng tower and ~prove physical properttes of h~gh ~surfactant spray drted partlcles, alkyl sulf~te WtS remoYed from tbe~spray dry1ng process and included tn a separately made ~a.lkyl sul`fate~part~cle~. It has been found that re~oval of the alkyl sulfate fro~ tho spray drytng tower reduces the total a~ount of st1c b or~an~c ~atertal 1n spray drted ~base granules~, thus i~proving lu~ping and cak~ng properttes. It has ~lso been found thàt~add1ng the alkyl sulfate outside the spray drying tower ~ia a separate process reduces the total organic load in the tower, thu~
réduclnQ vis~ble plu~e and reductng env~ronmental ~pact.
It has further been found that production rates for nit-P (no phosphate) granu~es can be ~ncreased (up t~ about 30X; based on equiva~nt tower drying loads and crutcher mo~s~ures) if the alkyl sulfate i5 added as a separate part1cle.
It ~s bel1eved that remova~ of the other pr~dominant~
frequently-used anion1c su~factant, 11near alkylbenzene sulfonate ~LAS~, fram the spray dry1ng tower alone ~oes not result in ptume reduc~ion as does alkyl sulfate.
Product~on af alk~yl sulfate part~cles by continuous neutral~zat10n is described in Copendlng U.S. Patent Applicatton Ser~al Nu~bers 647~338 and 5~2,663 c1ted above.
s -~, ~ . .

93/02168 ~ ! l t 3 ~ 1 3 P~r/us92/os6s9 rn th~s process, spray dr~et granules are made by convent~onal spray dry~ng means. They are comprtsed of less than about 2Z alkyl sulfate, detergency builder, and soluble sll~cate.
Other detergent ~ngredlents conventtonally added tnto spray dr1ed granules may also be added here. Alkyl sulfate particlRs are made ~n a separate process using a continuous hlgh act~ve neutral~zatlon system (see below). The spray drted granules are then ad~xed ~lth the alkyl sulfate part1cles. Other convent~onal detergent 1ngred~ents ~ay also be ad~1xed.
10A consu~er acceptable product wh1ch can be made w1th less `~ ~ plume e~lsslon, h~gher product10n rates, and ~proved phys~cal properties is achtevable using th~s ~nvention. Also, surfactant leYels in a detergent compos~t10n can be easily increaset by ~; add~ng more alkyl sulfate part~cles to the co~postt~on. High , dens~ty granular tetergent composittons ara more eas~ly made because of the flexib~llty of mixing the alkyl sulfate parttcles.
Detergency bu~lder, soluble sil~cate, anion1c surfactant, and other des~red lngred~ents can be atded via the spray drled granules, and htgher levels of the alkyl sulfate, wh~ch are o d1 ff~cult to put into the spray dried granules, can be added v~a the alkyl sulfate part1cles.
The term part~cles is used interchangeably with granules herein. -I. ~lkYl Sulfate Part~cles ~5Alkyl sulfate part1cles are produced by steps comprls~ng cont~nuous high act1ve neutralization. These part~cle~ are comprised of, by weight of the alkyl sulfate particles, from about 60 to 9SX., preferably about 70 to 90Z. of C12 18, preferably Cl4_l6, alkyl sulfate ethoxylated w~th from O to about 4 moles of ethylene oxide per mole of alkyl sulfate. The alkyl sulfate ispreferably not ethoxylated (O motes of ethylene oxide)~ It ~s preferred that the alkyl sulfate particles contain from about 4 to 25X, preferably about 8 to 14%, by weight of the alkyl sulfate part~cles, of Clo l6, preferably Cll l4, linear alkylbenzene -3~

~nD93/02168 P~r/usg2los6ss ~113~13 sulfonate, especlally where nonethoxylated alkyl sulfate is used.
M1xtures of alkyl sulfate and alkyl ethoxy sulfate may be used.
~here alkyl ethoxy sulfate 1s uset, fro~ about 0.5 to 2 moles of ethylene oxide per ~ole of alkyl sylfate is preferred. Alkyl sulfate flakes are preferr~d.
Useful alkyl sulf~te surfactants are the water soluble salts, part1cularly th~ alkal1 metal, aJ~onium and alkanola D nium (e.g., monoethanola~ontu~ or trtethanolam~oniu~) salts of C12 16 ltnear or branched alkyl sulfates.
The alkyl sulfate partlcle making process co~prises the followlng steps.
A~ Add~tton of Ac~d and Caust1c The f1rst step of th1s process is reacting 1n a continuous neutral1zat10n syste~ C12 18 alkyl (ethoxylated) ~sulfuric ae1d,-~
and preferably Cl0-l6 alkyl benzene sulfonic acid or ~1xtures thereof, w1th a sod1u~ hydroxide solution, which is greater than or equal to about 62X by w~1ght of the hydroxide, preferably w~thout knead1ng, to produce a neutral1zed product. The neutral1zed product pref~rably has less than or equal to about l2S
~o ~Y weight of water.
~;~ rt is preferred that the materials of the detergent co~position not be kneaded in the co~t~nuous neutral1zatioR
system. The cont1nuous neutral1zation system preferably does not lnclude an a1r~ight-type kneader.
2~ It is preferred that the continuous neutralizat10n system be substant~ally free of atdttion~l crude ma~ar~als of the detergent composition. In other words, crude materials other than surfactant, caustic and~or polyethylene glycol are preferably not fed into the system~ For example, less than about 5X, preferably less than about 1%, of add1tlonal crude mater1als should be present in the cont1nuous neutralizatton system. It ts most preferred that essent1ally no detergency builders or add1t10nal .organ1c mater1a~1s are fed into the continuous neutralizat10n system.
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~"~) 93/02168 PCI/US92/056D
~113413 :

The C12 18 alkyl (ethoxylated) sulfurtc acid and C10-l6 alkyl benzene sulfonic ac~d can be 0ade by any sulfation/sulfonat~on process, but preferably are sulfonated with S03 in air in a falling fflm reactor. See Svnthetic Deteraents, 7th ed., A.S.
Oavidson ~ B. Milwidsky, John ~1ley ~ Sons, Inc., 1987, pp.
151-168.
C12 18 alkyl sulfuric acit, and mixtures of it and C10~16 linear alkyl benzene sulfontc actd, are preferred for use heretn.
M1xtures of the two are ~ost preferred because of i~proved d~sperslbtlity of detergent particles formed fro~ a paste ~ade wtth the ~ixture. The two actds can be added as separate strea~s to the conttnuous neutral~zatton--system or mt%ed before additton.
Alternatively, pastes ~ade from each separate actd can be mixed after neutraltzation.
In thts process, it is preferred that the final ratio of C12 18 sodiu~ alkyl sulfate to C10-l6 sodium linear alkyl benzene sulfonate be between 75:25 and 96:4, preferably between 80:2C and 95:~.
C14_16 alkyl sulfuric actd is preferred for use in step (a) of thts process over C12_1g alkyl sulfurtc acidr C14 15 atkyl sulfuric acid is most preferred.
C11 14 linear alkyl benzene sulfonic acid is preferred oven Clo~l6 alkyl ben~ene sulhnic acid. C12 13 linear alkyl benzene sulfonlc acid ~s most preferred h r use herein.
The sodtum hydroxide used ~n step (a) to neutralize the alkyl sulfuric acid and/or alkyl benzene sulfonic acid is greater than or equal to about 62%, preferably greater than or equal to about 68X~ most preferably abaut 73%, by weight of the hydroxide. This highly concentrated caustic solutton melts at a htgh temperature so the caust~c feed system mùst be carefully matntained at the required temperature to prevent ~cold spots~. A ncold spot~ ls any point tn the hed syste~, pumps, metertnS syste~s, ptpes or valves where the system has reached a temperature below the melttng potnt of the caustic (155-f or 68.3-C for 73% caustic, for 3s WOg3J02168 P~/US92~05CS9 ~tt3913 example). Such a ~cold spot~ can cause crystal`l~zatton of the caust~c and blockage of the feed system. Typtcally "cold spots~
are avoided by hot water ~ackets, electrlcal trac1ng, and etectrically heated enclosures.
The sod1u~ hydroxide is preferably present in sltght excess of the stoich1Ometric a~ount necessary to neutral~ze the acit. If excess alkal1nlty ~exeess causttc) in the neutral~zatton syste~
exce~ds about l.SX M20 (where M ls ~et-l), the paste ls dt~ftcutt to circulate through the cont1nuous neutral1~atton system because 0 of lts h~gh v~scostty. If excess alkalin~ty drops below about O.lX, the alkyl paste ~a~ not be stable long term because of -` hydrolysis. It ts therefore preferred that excess alkalinity, whtch can be ~e2sured by tttratton with acid, of the molten paste ~n the neutr~l1zatlon syste~ bc between about 0.1% and 1.5%, ~ore 1~ preferably bet~een about O.ZX and l.OX, most preferably between about 0.3X and 0.7X.
The acid and causttc are put tnto the cont~nuous neutraliz-atlon system separately, pref~rably via a htgh shear m~xer so that they ~ix together as rapidly as posslble. The h~gh shear mixer ls ~o preferably spec1ff cally destgnet for complete mtxlng of viscous liqutds.
6enerally, in a cont~nuous neutralization loop, the ingredients enter the syst~m through a pump ~typically centrifugal) wh1ch circulates the material through a heat exchanger ~n the loop and back through the pump, where new mRterials are introduced. The material in the system continually recirculates, w1th as much product exiting as is enter1ng.
Product ~xits through a control valve which is usually after the pump. The recirculat1On rat1a of a cont~nuous neutralizat1On loop is between about 1:1 and S0:}. ~he temperature o~ the neutralization reaction can be controlted somewhat by ad~usttng the a~ount of cooling by the heat exchanger. The ~throughput~ can be controlled by modifying the amount of acid and caustic 1ntroduced~
~;~ ' ` .................... '``'' .
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~"~) 93~0216~ /US92~0S659 7113~13 The continuous neutralizatton loop should be modiff ed as follows to practice this process:
(1) Insulate the loop;
(2) Change the centr~fugal pump to a pos1t~Ye d1splacement pu~p, wh1ch is better able to handle very v1scous r ~ater~al;
(3) Install a caust~c feed syste~ wh~ch can handle ~; concentrated caustic (greater than about 50% sol~ds);
lo ~4) Introduce ~ater~als through a h~gh shear mtxer installed ; ~ in-line;
~-~ ' (S) Install a ~etering syste~ for the polyethylene glycol and/or ethoxylated non~on~c surfactant, preferab~y after the high shear mixer; ant (6) Pos1t~on the inco~ing streams of ac1d and caustic at the h~gh shear mixer so that the highest degree of mixing posstble takes place.
(7) The temperature of the loop should be sufff ciently high to ach~eve a low v1scos~ty of the paste to ensure ;:
adequate reclrculat1On and m~xing. The te~perature should not be so high however that it causes hydrolysis of the alkyl sulfuric acid or the alkyl sulfate.
Typical paste temperatures in the loop are between about~
180-F (82.2-C) and 230-F (llO-C), preferably about 200-F
(93.3-C3 to 210~F (98.9-C~.
. Addition of PolvethYlene Glvcol and/or Ethoxvlated Nonion~c Surhctant An optional second step of this process is adding to the continuous neutralization system tur~ng formation of the neutral~zed product polyethylene glycol of a molecular we19ht between about 2,000 and 50,000 and/or ethoxylated non~onic surfactant of the h nmula R(OC2H4)nOH, wherein R is a C12 18 alkyl group or a Cg l6 alkyl phenol group and n is from about 9 to about ~- 80, witb~a ~eltSng point greater than or equal to about 120-F
3~ -, .

WOg3/02168 2 1 1 3 4 1 3 pcr/us92~o5c59 (48 9 C) The wetght rat~o of the addlt~ve of step (b) to the mixture of step (a) 1s fro~ about 1 5 to about 1 20 The polyethylene glycol and/or the ethoxylated nonlontc surfactant can be added separately or as a m1xture to the contlnuous neutral~zatlon syste~ at any polnt. In a nèutral~zat~on loop these add1tlve(s) prefer~bly enter the loop aftQr the h~gh shear ~xer ~nd before the rectrculatlon pu~p The atdlt1ves ~ust be ~elted before addtt10n to the neutraltzatton syste~ so that they can be ~etered ~n These two add1tl~es are chosen because they enhance detergent p~rfor~ance and are sol1d at below about 120-f (~8 9 C~ so that a detergent part1cle whtch ts finm at amb1ent temperature can be made from the neutralized paste ~hey are also chosen because each add1t~ve acts as ~ process aid by reducing the viscos~ty of the-h~gh acttve paste in the neutral~zer loop Thts viscostty reductlon is part1cularly l~portant dur1ng the start up of the neutralizer loop where the s~rfactant concentrat~on is ~ncreased through the ~ddle phase~ reg1On. So~e alkyl sulfate ch~tn lengths have very high ~tddle phase~ vtscosttles - typ1ctlly o between concentrations of 40X and 60% r Polyeth~lene glycol of a molecular weight between abou~ 2 000 and 50 000 is pre~erred over the ethoxylated nonionic surfactants, Polyethylene glyco~ of a ~oleeular weight between about 3 000 and 20 000 pre h rably 7 000 and 12 000 ts ~ore preferred and ~4st preferred is pol~ethylene glycol wtth a moletular we~ght of 8 00Q
PEG 8 000~) In thts invent~on the preferred wetght ratto of polyethylene glycol to the actd/causttc mi`xture of step ~a) ts from about 1 8 to about 1 12~ For polyethylene glycol with a molecular weigh~ of 8 000 the preferred weight ratio is one part 3~ PEG 8 000 to ten parts actd~causttc mtxture Polyethylene glycol is for~ed by the polymerlzatton of ethylene glycol w~th ethglene oxtde ~n an a~ount suff~c~ent to provtde a co~pound with a ~olecular weight between about 2 000 and 50 000 It can be obtatned from Unton Carbtde (~anbury CT) ;35 '' .::

~"' g310n68 Pcr/uss2/0s6ss :~113~1~

The preferred ethoxylated nonionic surfactant material is of the hrmula R(OC2H4)nOH, wherein R is a C12_1g alkyl group and n i`s from about 12 to about 30. Most preferret ~s tallow alcohol ethoxylated with 18 moles of ethylene ox~de per mole of alcohol ; (~TAE 18~). The prefcrred ~elt~ng point for the ethoxylated non~on~c surfactant ~s gr~ater than about 140-F (60^C).
Examples of other ethoxylated non~onics here~n are the condensat~on products of one mole of decyl phenol w~th 9 moles of : ethylene ox~de, one mole of dodecyl phenol with 16 moles of lo etbylene ox~de, one mole of tetradecyl phenol with 20 moles of : etbylene ox~de, or one mole of hexadecyl phcnol w~th 30 moles of ethylene ox~de.
Cont~nuous neutral~zat~on can be conducted by a process co~pr~s~ng the steps of:
(a) reacting ~n a h~gh act1ve cont~nuous neutralization loop the ac~d form of sa~d alkyl sulfate w~th sodium hydrox~de sotutton, wh~ch ~s abut 30 to 75% by weight of : the hydrox~de and is present in sto1ch~ometric amount to ; slight sto~ch1O~etrlc excess, th produce a neutral1zed ~o product;
(b) adding to said cont1nuous high act~ve neutral~zat~on loop, during formation of sa~d neutral~ted product, an ~-aminodicarboxyl~c acid selectet from the group cons~sting of glutamic acid, aspartic acid, aminomalonic acid, a~inoad~p~c acid, and 2-aminio-2-methyl-pentaned~otc acid, or the~r alkali metal salts, such that partlcles formet from the product of step (b) are compr~sed of from about 0.2 to 15 weight % of the ~-a~inodicarbo%yl~c acid salt.
30 An alkali metal salt of glutamic acid or aspart~c acid is preferably added to the neutral~zat~on loop. Preferably, from about l to 10 we~ght % mono- and/or d~sod~um gluta~ate ~s added to ; the neutral~zat~on loop.

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WOg3/021C8 PCr/US92!05659 ~'1 13~13 The alkal~ metal hydroxide solution is preferably about 62 to 73X by weight of the hydroxide. Sodiu~ hydroxlde is preferred.
The neutralized product preferably has less than or equal to about 12% by weight of water.
C. formatton of Part1cles The th~rd step of th1s alkyl sulfate particle-making process is for~ing detergent part~cles. Detergent particles can be formed tn var~ous ways fro~ the neutral1zed product ex~t~ng the cont~nuous neutral~zation system. k tesirable detergent particle s1ze dlstribut~on has a range of about 100 to 1200 microns, preferably about lS0 to 600 ~icrons, with an average of 300 , ~
~lcrons.
The ~olten p~ste fro~ a cont1nuous neutral1zatton loop can be ato~ized into droplets ~n a prilling (cooling) tower. To avoid IS~ pr~lt~ng at all, the molten paste can be s~multaneously cooled and extruded " nd cut or ground ~nto desirable particle sizes.
A thtrd cho~ce is to allow the ~4lten paste to cool on a `~chill roll, or any heat exchange un1t unt~l it reaches a doughy cons~stency~ at whlch point other detergent lngredients can be 0 kneaded in. The resulting dough can then be- granulated by mechanical ~eans.
A fourth and preferred choice is to cool the molten paste into flak~s on a chlll roll, then grind the flakes to the des~red part~cle s~ze. If add~ttonal drying is requ~red, the cooled ~5 --flakes can be dried in a rotary drum with hot air or ~n a flu~d bed prior to grinding.
` II. rav Dried 6ranules The spray dried granules for use in this process can be made~
by any conventional spray drying process. They are made by a spray drying process compris~ng spray dry~ng a slurry compris~ng, by weight of the spray dr~ed granules: less than about 2X of alkyl sulfate; from 0 to about 40X of anionic surfactant other than . ..
~ ~ alkyl sul~ate; fro~ about 10 to 80% of detergency bu~lder; and , .

V~l93/OQ1C8 Py~rruss2/os6ss '113413 from about 1 to 15%, prehrably 2 to 5%, of soluble sil~cate (as a structurantJ.
From about S to 30X of anionic surfactant is preferred. The anionic surfactant is preferably a satt of C10-l6 linear alkylbenzene sulfonate. From about 10 to 20X of sodium Cll l4 r linear alkylbenzene sutfonate is mast prehrred.
Nil-P granules are preferred. The spray dried granules are preferabl~ co~prised of fro~ about 30 to 60 weight % of detergency builder selected from the group consisting of carbonate, c~trate, alu~inosillcate, and mixtures thereof. Host preferably, from about 5 to 60 welght X of sod~um carbonate and/or water-soluble inorganic salt, preferably sodiu~ sulfate, is included.
In one embodiment, the spray dried granules are comprised of fro~ about S to 50 weight % of sodlu~ aluminosilicate.
Applicable spray drying processes are described in U.S.
~` Patents 4,715,979, Moore et al, issued December 29, 1981, ;; 4,963,226, Chamberlain, issued October 16, 1990, and 4,344,871, -~
Allaway et al, issued August 17, 1982, which are incorporated here~n by reference.
o III. Admix r The spray dr~ed granules and the alkyl sulfate particles are ad~ixed~ respectively, at a ratio between about 10:90 and 99~
more preferably between about ~0:50 and 99:1, more preferably between about 70:30 and 9Q:10, most preferably about 85:15.
Admixing can be by conventtonal means. Preferably, from about 2 to 40%, by weight of the ff nished composition, of detergency builder is admixed with the (finished) granules.
The alkyl sulfate particles and said spray dried granules are preferably ad~ixed with from about 3 to 1~X, by weight of the f~nished composit~on, of citric acid and effective amounts of perfume and enzy~es.
IV. Comoos~tion Claims Two inventions are believed to be contained herein: the process for making the co~position, and the composition itself.
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WO 93/021C8 . I'CI`/US92/056S9 ~113913 The latter comprises alkyl sulfate particles which include from about 4 to 20% of C10 16 linear alkylbenzene sulfonate and/or C12-18 (coconut) soap for enhanced solub~l~ty in cold water. the alkyl sulfate is included in the high acttve part~cles rather than in the base granules for the.same reasons as are stated ab~ve.
Included is a granul~r detergent com4osit~on compristng bj welght of the f1n~shed co~pos~tton:
(a) fro~ about 1 to 90X of alkyl sulfate partlcles compr~stng by weight of the alkyl sulfate particles:
from ~bout 60 to 99% of C12 18 alkyl sulfate ethoxylated w~th fro~ 0 to about 4 moles of ethylene oxlde per ~ole of alkyl sulfate; fro~ about 4 to 20~ of C10_16 l~near alkylbenzene sulfonate and/or C12-l8 soap; and :
. (b)...from about 10 to 99X of base granules comprised of by :~ 15 weight of the granules less than about 2% alkyl sulfate . and fro~ 0 to about 40X of anionic surfactant other than alkyl sulfate; from about 10 to 80~ of detergency ~: builder; and fro~ about 1 to 15X of soluble silicate~; A preferred granul~r detergent co~pasttlon herein co~prises ~o by we~ght of the f~ntshed composlt~on: ~
(a) from about 1 to 90X of alkyl sulfate part kles consistlng essent1ally of by wetght of the alkyl sulfate part~cles from about 60 to 9~% of C~2 18 alkyl sulfate; from about 4 to ~OX of Clo i6 l~netr alkylbenzene sul hnate and/or C12 18 soap; from about 5 to 2~Z of polyethylen.e glycol of molecular we19ht betwaen about 2 000 and S0 000; from about 0.2 to 15X of an ~-aminod~carboxyl~c acid sele~tet ~rom the group eonsi.sting of gluta~ic acid aspartic acid aminomalonic ac~d aminoadipic acid and 2-amino-2-methyl-pentane-d~oic ac1d or the~r alkali metal salts; and from about 1 to 15% of water and/or unreacteds; and (b) from about 10 to 99~ of base granules comprtsed of less than about 2% phosphorus.

~ 93/02168 P~:r/USg2/05659 ~113413 The spray dried granules are preferably comprised of from 0 to about 40%, preferably about 2 to 40% of anionic surfactant other than alkyl sulfate; from about 10 to 80% of detergency builder; and fro~ about 1 to 15% of soluble s~licate.
3 The spray dried granules are pre h rably co~prised of from about 1~ to 20X of C10 16 l~near alkylbenzene sulfonate and from about 2 to 5X of soluble sodiu~ silicate. The spray dr~ed g n nules are also preferably comprised of from about 30 to 60 weight % of a detergency builder selected from the group consisting of carbonate, citrate, aluminosil~cate, and mixtures tbereof. They are ~ore preferably co~prlsed of fro~ about S to 60 weight % of sodiu~ carbonate and~or sadlu~ sulfate.
The spray dried granules are preferably further comprised of fro~ about 1 to lOX of a ho~opoly~er or copolymer of acryl~c acid or its salts having an a~erage molecular weight be~ween about 1,000 and 10,000. ~he granular detergent composition herein preferably has a phosphorus content of less than about 2.0, preferably 0.
The foltowing are separately preferred for the alkyl sulfate ,0 ~particles of (a): 11near alkylbenzene sul h nate range is fro~
about 6 to 12% of Cll l4 LAS; alkyl sutfate range is from about 65 to 90% of C14 16 alkyl sulfate; polyethylene glycol range is fro~
about 5 to i5% at a ~olecular weight between about 4,000 and 12,000; a-aminod~carboxylic ac~d s~lt range is from about 1 to 3%

5 and is most preferably mono- and/or disodium glutamate; and the water and/or unreacted materials range ~s from about 2 to 8X.
Preferably, the ratio of LAS to alkyl sulfate is between about 60:40 and 80:20, most preferably ~0:30.
The composition preferably further comprises ~adm~xed on top f both types of granules~: (c) from about 2 to 40X, preferably S
to 15%, by we~ght of the finished composition, of detergency bu~lder, or (c) fro~ about 3 to 10%, by weight of the finished co~position, of citric ac~d and effective amounts of perfume and en2ymes. Enzy~es. preferably protease~ lipase and/or cellulase, 3~ ~

:~ ~

~WD93/02168 P~r/us92~o56s9 ~113413 ,5 comprise less than about 3X by weight of the composit~on, as do perfumes.
The rat~o of ta) to (b), respect~vely, is preferably between about 50:50 and 1:99, ~ost preferably between about 30:70 and 10:90. :~.
V. QDt~onal In~redients Exa~ples of detergent surfactants which can be è~ployed here1n are descr1bed ~n U.S. Patent 3,57g,454, Collter, issued May la, 1971, ~ncorporated herein by reference, fro~ Column 11, line ..
45 through Column 13, l~ne 64. An extensive tiscussion of surfactants ls cont~1n~d 1n U.S. Patent 3,936,537, incorporated herein by reference part1cularly Column 11, line 39 through Colu~n 13, line 52. Anion~c synthetic surfactants are particularly preferred.
Cat1Onic surfactants can also be included in such finished detergent co~pQsit1Ons. A more co~plete disclosure of these and ~`~ other cationic surfactants useful herein can be found in U.S.
Patent 4,228,044, Ca bre, ~ssued October 14, 1980, incorporated herèin by reference. - -Other opt1Onal ingredients which may be included in the detergent compositions herein include detergency builders, chelating agents, bleaching agents, antitarnish and anticorrosion agents, perfumè and color add1t~ves, and other opt~onal ingredients enumerated ~n the Basker~itle patent, U.S. Patent ~S 3,936,537, from Column 19, l~ne 53 through Column 21, line 21, incorporated herein by reference. Ch~lat~ng agents are also described in U.S. Patent 4,663,071, Bush et al., from Column 17, line S4 through Column 18, line 6~, incorporated herein by reference. Suts mod1f~ers are also opt~onal ingred1ents and are describe~ in U.S. Patents 3,933,672, issued January 20, 1976 to Bartoletta et al., and 4,136,045, issued January 23, 1979 to Gault et al., both incorporated herein by reference. ~etergency . builders are enumerated in tbe Baskerville patent from Column 13, -~ ~ line 54 through ~olumn 16, l~ne 16, and in U.S. Patent 4,663,07I, `'"~ 93/02168 P~/US92/05659 ~113~13 Bush et al., issued May 5, 1987, both ~ncorporated herein by reference. Such builders ~nclude, hr example, phosphates, -aluminosil~cates, silicates, carbonates. C10-C18 alkyl monocarboxylates, polycarboxylates, `and polyphosphonates, and -m1xtures thereof.
Alt parts, percentages and rattos used here~n are by weight unless otherwfse speciff ed.
EXAMPLE I
An alkyl sulfate part~cle is made according to the following for~ula:
~ ~ei~ht - Sodiu~ (C14 15) alkyl sulfate 72.8Sod~um linear (C12 3J alkyl benzene sulfonate 10.6 ~ater 2.0 -~ I; Sod~u~ sulfate 1.6Polyethylene glycol tM~ 8000) 8.3 Mono/d1sod~um glutamate 2.1 H~seellaneous 2.6 Detergent compositions are made by first spray drying aqueous 0 slurries according to the following for~ula: ' Weiaht X
Product A Product B
~Control) tT~st) Sodium linear (C12.3~ alkyl- 14.88 15.39 '5 benzene sul hnate Sodium (C14_1S) alkyl sulfate 6.38 0.00 Sodlum carbonate 10.96 I2.02 Sot~um polyacrylate (MW-4SOO) 3.51 3.8S
Sodium aluminos~licate 29.48 32.34 Sodium sil~cate (1.6 S~02:Na20) 2.41 2.64 fluorescent whitening agent 0.30 0.32 Sodium sulfate 21.S8 22.79 Polyethylene glycol (M~-8000) 1.62 0.99 Oeaerant* 0.11 0.12 - 3, ~ ~ ~ .. ........ ....

WO 93/02168 P~/US~ 659 ~113413 Moisture 8.77 9.54 *Dow Corning DC-544 Spray dry~ng was performed in a ten foot diameter counter current spray drying tower with a single nozzle at 740 lb/hr, ~nlet a1r temperature of approxtmately 390-F and exhaust te~perature of approxl~ately 200-F.
F~n~l d~t~r~ent co~postt~ons are then madQ by ad~xing aeeord1ng to the following formula: -Spray drted granules 91.24 83.16 t1tr~c ac~d 5 5 5-5 0.30 0.34 Protease/A~yl~se 0.9 0.9 A~oniu~ sulfate 2 2 Alkyl sulfate parttcles . 0 8.01 ~ s Suds sùppressor 0.06 0.06 ;~ ** Alcalas~R~p1dase (Novo) Product A represents a control detergent compositton, produced as descr~b~d ~bove. Product B ts st~ilarly produced except for the ~nclus10n of ad~ixed alkyl sulfate part~cles. It 20 1s che~tcally equ1valent to the control.
~, .
Results - ~hen the two laundry products described above are evaluated by consu~ers dùrtng a t~o week per10d in their homc washing machines tstngle product blind tes~, they are rated equal.
?5 Cat~clusiQn The alkyl sulfate part~tle/spray dried granula admix al~ows product~on of laundry detergents which are chemically equivalent to current detergent compositions wi~h no changs in consumer percept10n. The admix provides the processing advantage of 1ncreased capacity and reduced organic em~ssions from the spray drying tower.
EXAMPLE II
Alkyl sulfate part~cles as described in Example I can be used :
in tbe fo~lowing detergent formulation.

'`; ~' ` ' , , . ~ .

~`") 93/02168 PCI~/USg2/0565g Z113~13 ~eiaht %
~ Product C Product D
:: (Control) (Test) Sod~um linear (C12.3) a?kyl- ` 9.70 8.29 benzene sulfonate Sod1um (C1~ 1S) alk~l sulfate 9.70 0.00 Sodtu~ c~rbonate 10 10 Sod1u~:poly~cr~rlate (M'~l 4500) 3.2 3.2 ~;
Sod~u~:alu~nosillcate 26.9 26.9 0 ~ Sod~us~s1llcate~ -6 5lo2:Na2o) 2.2 2.2 Fluore~sc nt:wh~:ten~ng agent 0.27 0.27 Sod~`u~ sulfate : 19.69 18.82 Polyethylene glycol (M~8000) 1.48 0.37 r~ o l 0 1 :~

Ad~xed-::
C~tr~c~c~d 5.5 5.5 ~e 0.30 Q.34 Proteas-/~lase 0.9 0.9 o~ Ammon~u~ sulfate 2 2 Al-kyl sulfate part1cle 0 13.32 Suds suppressor 0.06 0.06 ~: *Dow Corning DC-~44 : ** Alcalase/Rapidase (NoYo) These for~ulae are again chemically e~u~valent to each other.
Product C, the control, ~s the same as Product A? the control in Example I, except the rat1O of the surhctants a1ky1 sulfate:linear alkylbenzene sul hnate is changed from 30:70 to 50:50. Product C is no longer manufacturable by spray drying due 0 to env~ronmental constra1nts on the res~tual organics introduced to the spray drytng tower by the addltlonal alkyl sulf~te.
Ho~ever,~Product:0 can:be produced w~th less environmental i~pact than~:-`evèn~Product A. Product: D would be expected to perfor~

WO g3/02168 Pcr/uss2/0s6ss ~113~13 ,9 :
better in contexts where a!kyl sulfate is the preferred surfactant.
EXAMPLE III
Alkyl sulfate parttcles as descr1bed 1n Example I can be used ' in the followtng detergent for~ul~t~ons:
~e1aht %
Product E Product f (Control) (~est) Sodlu~ l~near (C12.3) alkyl- l9.09 17.90 b~nzene sulfon~te Sodlu~ ~Cl4 l~) alkyl sulfate 8.18 0 Sod~u~carbonate ~ lO lO
Sod1u~ polyacrylate (M~ 4500) 3.2 3.2 Sodtu~ ~lu~1nos~1ic~te 26.9 26.9 Sodtu~stl1cate (1.6 St0?.:N~20) 2.2 2.2 Fluorescent whttenlng agent 0.27 0.27 Sod~u~ sulfate 11.82 11.06 Pol~ethylene glycol ~M~-8000) 1.48 0.55 D~aerant* 0.1 O.l 0 ~Mo1sture 8. ~ 7.78 Ad~lx~d -C~trlc ac~d 5.5 5~5 Perfu~e 0.30 - 0-34 Protease/Amyl?se 0.9 C.9 7~ Ammon1um sul~ate 2 2 kyl sulfate particles 0 11.24 Suds suppressor 0.06 0.06 *~ow Corning DC-544 *~ Alcalase!Rapidase ~Novo) These formulae are che~cally equivalent to each other.
Product E, the control, is the same as Product A, the control in Ex w le- I, except the total surfactant (11near alkylbenzene ; suifonate plus alkyl sulfate) in the fonmula is increased ~ro~
19.40% to 27.27X~ Product~E can no longer be manufactured by 35~

~ 93/02168 PCI~/USg2/05659 ~ 113413 spray drying for reasons of safety and environmental impact and because the physical properties of the spray drled granules would be expected to be poor (~.e. lu~ping and cak1ng). However, Product F îs ~anufacturable by the co~binatton of spray drying and admix~ng of alkyl sulfate part~cles. This product would be expected to perfon~ better than Product A on surfactant sensitiYe soils.
EXAMPLE IV
~he hllowing detergent compositions are mate on a ten-foot 10 di _ ter counter current spray drying tower:
Control 1~
Sodium C12 3 alkylbenzene sulfonate 11.45 11.27 Sodiu~ C14.s alkyl sulfate 11.45 o Sodium~alu~inosilicate (hydrated, 28.90 28.90 20% water) Sod1u~ carbonate 17.00 17.00 Sodiu~ silicate (1.6 Sio2:Na2or) 5 35 5 35 Sodiu~ polyacrylate (M~-4500) 3.5 3.5 Polyethylene glycol (MW-8000) 1.2 0 Fluorescent whitening agent 0.22 ~ 0.22 Tallow fatty ac~d 1.28 1.28 ~atert sodiu~ sulfate rest rest Cake 6rade Resul~s:
Force (lbs/in2) to break cake 5.2 2.3 ~5 under 20 lb load Water by analysis 11.4 11.1 The impro~ed physical property (lower cake grade) o~ the test product de~onstrates the advantage of minimizing the surfactant content of spray dr~ed granules. This is true even though the crispening aid, polyethylene glycol (MW~8000), is remoYed along with the ~ost crisp surfactant, alkyl sulfate.
EXAMPLE V
Preparation of high active detergent material suitable for granulation to a free flowing particulate is as follows.
,~

~r.o g3/02168 PCr/US92/OSCSg ,t.~.'113~13 9uiDment - .
A falling f~lm S03 reactor ~s used to prepare the aclt form of Cl4 15 alkyl sulfate. The ac~d is fed to a h~gh acttve neutralizat~on system supplled by Chem~thon Corporation of Seattle, Wash1ngton. Th~s custo~ized neutralization system consists of a recycle loop contain1ng a heat exchanger for cooltng, a rectrculation pump sultable for hlghly viscous fluids, and a h1gh shear mlxer w1th whtch the reactants are introduced.
In order to attaln the very low ~otsture levels necessary for a free-flowtng, h~gh act1ve part~cles, the neutral~zatlon l~op is mod1fted to handle 70X sodtu~ hydroxide ~elt rather than the 38-50X non~ally used with the neutral~zat1On loop. The ~odlftcat1On conststs of hot water ~ackets and electr~cal heating of the caust~c feed syste~ to ~a~ntatn the 70X caust~c above the caust~c melttng potnt of about 155-F (68.3-C).
Another necessary modlficat~on is the addttlon of a ~etering system whtch in~ects the polyethylene glycol into the ~ neutral~2atlon loop at the dlscharge s~de of the hlgh shear ~xer.
- - The presence of the polyethylene glycol facilttates pumping of the ~o paste ~n the rec1rculat1On loop and reduces stick~ness of the flnished mater~al. Polyethylene glycol having a molecular weight of about 8000 ~s added ?s a ~elt (about 160-F or 71.1-C) at a rate o~ about 1 part polyethylene glycol 8000 t~ lO parts Cl4 l~ sodium alkyl sulfate active.
peration At start up, the neutrali-zation loop is filted with water and the system is maintained at 180-Z30-F (82..2-llO-C) by using hot water in the heat exchanger and tn the double wall pipe comprising the recycle loop. The recycle pump and h~Qh shear mixer are started.
The 70% sodium hydroxide and Cl4 15 al~yl su~furic acid are ~ introduced into the btgh shear mixer and allowed to react. The ;~ sod~u~ hydrox~de and C14 15 alkyl sulfuric acid are metered to allow a slight excess of sodium hydroxide. Material displaced ~ ~ .
.

~'' g3/02168 PCI~/US92/O!KS9 '~113413 from the recirculation loop is discharged through a back pressure control valve.
As operation continues, the water is displaced from the loop and the concentration of the sodium C14 15 alkyl sulfate is lncreased to over 70% act~ve. Operatlon ~s continued until the des1red a~ount of h~gh act1ve, lo~ ~o~sture ~aterial is produced.
The reactant feed ~s then shut off and the react~on loop is washed w~th bot water.
Results 0 The ~olten paste produced is cooled and manually ground to a fre~-flow1ng part~culate product having the follow~ng compos1t10n.
Sod~u~ C14 15 alkyl s~lfate- 74.S~
Polyethylene glycol 8000 8.5 ~ter g.1 .
~5 Sodiu~ hydroxide 0.6 Unreactants/~iscellaneous 6.9 EXAMPLE VI
An alkyl sulfate particle is ~ade accord1ng to the following for~ula:
o Nominal Wt%
~: Sodium (C14 15) alkyl sulfate 75.0 ~ater 11.0 Sod~um sulfate 2.5 Polyethylene glycol ~ 8000) 7.5 ~; Miscetlaneous 4.0 Detergent compositions are made by first spray drying aqueous slurr~es according to the hllowing formula;
We~aht 70 Product A Produ~t B
(Control) (Test) Sodiu~ linear (C12.3) alkyl- 11.90 13.25 benzene sulfonate ;~ Sod~um~(C14 1s) alkyl sulfate 11.02 0.00 ~ Sod~um carbonate 18.21 18.87 ~ ~ 33 ~0 93/02168 Pcr/us92/o56s9 ~113~ 13 Sodium polyacrylate (M~-~500) 3.34 4.12 Sodium alumtnosil~cate 23.39 31.40 Sodium silicate (1.6 5~02:Na2o) 1.82 1.90 Fluorescent whitentng agent 0.31 0.28 Sod~um sul~ate . 15.08 20.94 Polyethylene glycol (M~8000) 0.94 0.32 Sodtun tallow sope 1.03 1.36 Motsture 7.96 7.56 Spray dry~ng is perfor~ed ~n a ten foot diameter counter current spray drying tower wtth a slngle nozzle at 740 lb/hr, tnlet a~r te~pertture of approxtmately 390-F and exhaust - temperature of approx1mately 2~0-f.
ftnal dete~gent co~postttons are then made by admixing according to the follow~ng for~ula: -Spray drled granules 100.00 84.37 Al bl sul~ate parttcle 0 15.63 Product A represents a control detergent composttton,~
produced as descrtbed above. Protuct B 1s stmilarly produced except for the tncluston of ad~1xed alkyl sulfate particle. It ts che~lcally eq~ivalent t~ the control.
Conclus10n The alkyl sulfate particle/spray dried granule admlx allo~s product10n of laundry detergents which are chemically equivalent to current detergent co~posltions. The admix pr~vides the 2~ processing advantages of increased capacity and reduced organ1c e~iss~ons from the spray drying tower.

Claims

CLAIMS: -

1. A process for the production of a granular detergent composition, comprising:
(a) spray drying a slurry comprising, by weight of the spray dried granules: less than about 2% of alkyl sulfate;
from 0 to about 40% of anionic surfactant other than alkyl sulfate; from about 10 to 80% of detergency builder; and from about 1 to 15% of soluble silicate;
(b) producing alkyl sulfate particles by steps comprising high active continuous neutralization, said particles comprising, by weight of the alkyl sulfate particles:
from about 60 to 99% of C12-18 alkyl sulfate ethoxylated with from 0 to about 4 moles of ethylene oxide per mole of alkyl sulfate; and (c) admixing said spray dried granules with said alkyl sulfate particles in a ratio between about 10:90 and 99:1.

2. A process according to Claim 1 wherein said anionic surfactant in said spray dried granules is a salt of C10-16 linear alkylbenzene sulfonate.

3. A process according to Claim 1 wherein said spray dried granules are comprised of from about 30 to 60 weight % of a detergency builder selected from the group consisting of carbonate, citrate, aluminosilicate, and mixtures thereof.

4. A process according to Claim 2 wherein said spray dried granules are comprised of from about 5 to 50 weight % of sodium aluminosilicate.

5. A process according to Claim 3 wherein said spray dried granules are further comprised of from about 5 to 60 weight % of sodium carbonate and/or water-soluble inorganic salt.

6. A process according to Claim 5 wherein said slurry further comprises from about 2 to 5% of soluble sodium silicate.

7. A process according to Claim 1 wherein said high active continuous neutralization is conducted by a process comprising the steps of:
(a) reacting in a continuous neutralization system C12-18 alkyl sulfuric acid with a sodium hydroxide solution, which is greater than or equal to about 62% by weight of the hydroxide, to produce a neutralized product;
(b) adding to said continuous neutralization system during formation of said neutralized product, polyethylene glycol of a molecular weight between about 2,000 and 50,000; ethoxylated nonionic surfactant of the formula R(OC2H4)nOH, wherein R is a C12-18 alkyl group or a C8-16 alkyl phenol group and n is from about 9 to about 80, with a melting point of greater than or equal to about 120°F (48.9°C); or mixtures thereof;
wherein the weight ratio of the additive of step (b) to the product of step (a) is from about 1:5 to about 1:20.

8. A process according to Claim 7 wherein C10-16 linear alkylbenzene sulfonic acid is also added to said continuous neutralization system, such that said alkyl sulfate particles contain from about 4 to 25% of C10-16 linear alkylbenzene sulfonate.

9. A process according to Claim 7 wherein the materials of the detergent composition are not kneaded in the continuous neutralization system.

10. A process according to Claim 7 wherein said continuous neutralization system is substantially free of additional crude materials.

11. A process according to Claim 10 wherein said continuous neutralization system does not include an airtight-type kneader.

12. A process according to Claim 9 wherein essentially no detergency builders or additional organic materials are fed into said continuous neutralization system.

13. A process according to Claim 12 wherein said neutralized product has less than or equal to about 12% by weight of water.

14. A process according to Claim 10 wherein said continuous neutralization system is a continuous neutralization loop.

15. A process according to Claim 10 wherein said additive of step (b) is polyethylene glycol of a molecular weight between about 3,000 and 20,000

16. A process according to Claim 14 wherein said weight ratio of the additive of step (b) to the product of step (a) is 1:10.

17. A process according to Claim 14 wherein said additive of step (b) is molten polyethylene glycol with a molecular weight of 8,000.

18. A process according to Claim 10 wherein R is a C12-18 alkyl group and n is from about 12 to about 30.

19. A process according to Claim 1 wherein said high active continuous neutralization is conducted by a process comprising the steps of:
(a) reacting in a high active continuous neutralization loop the acid form of said alkyl sulfate with sodium hydroxide solution, which is about 30 to 75% by weight of the hydroxide and is present in stoichiometric amount to slight stoichiometric excess, to produce a neutralized product;
(b) adding to said continuous high active neutralization loop, during formation of said neutralized product, an .alpha.-aminodicarboxylic acid selected from the group consisting of glutamic acid, aspartic acid, aminomalonic acid, aminoadipic acid, and 2-amino-2-methyl-pentanedioic acid, or their alkali metal salts, such that particles formed from the product of step (b) are comprised of from about 0.2 to 15 weight % of the .alpha.-aminodicarboxylic acid salt.

20. A process according to Claim 19, wherein an alkali metal salt of glutamic acid or aspartic acid is added to said neutralization loop.

21. A process according to Claim 20, wherein said alkali metal hydroxide solution is about 62 to 73% by weight of the hydroxide.

22. A process according to Claim 21, wherein from about 1 to 10 weight % mono- or disodium glutamate is added to the neutralization loop.

23. A process according to Claim 19, wherein said alkali metal hydroxide solution is sodium hydroxide.

24. A process according to Claim 20, wherein said neutralized product has less than or equal to about 12% by weight of water.

25. A process according to Claim 19, comprising the additional step of adding to the neutralization loop during formation of said neutralized product, polyethylene glycol of a molecular weight between about 2,000 and 50,000; ethoxylated nonionic surfactant of the formula R(OC2H4)nOH, wherein R is a C12-18 alkyl group or a C8-16 alkyl phenol group and n is from about 9 to about 80, with a melting point of greater than or equal to about 120°F (48.9°C); ormixtures thereof in a weight ratio of from about 1:5 to 1:20 with the ingredients of step (a).

26. A process according to Claim 25, wherein polyethylene glycol of a molecular weight of between about 7,000 and 12,000 is added.

27. A process according to Claim 26 wherein said polyethylene glycol has a molecular weight of about 8000 and the weight ratio of said polyethylene glycol to the ingredients of step (a) is about 1:10.

28. A process according to Claim 19 further comprising simultaneously cooling and extruding the molten neutralized product, and cutting or grinding into detergent particles.

29. A process according to Claim 19 further comprising cooling said product of step (b) on a chill roll until it has solidified, and flaking said solidified product off said chill roll into detergent flakes, drying to below about 5% moisture, and mechanically grinding into detergent particles.

30. A process according to Claim 3 wherein said alkyl sulfate particles are comprised of from about 70 to 90% of sodium C14-16 alkyl sulfate.

31. A process according to Claim 1 further comprising admixing with said alkyl sulfate particles and said spray dried granules from about 2 to 40%, by weight of the finished composition, of detergency builder.

32. A process according to Claim 1 wherein the phosphorus content of said granular detergent composition is less than about 2.0%.

33. A process according to Claim 2 comprising admixing with said alkyl sulfate particles and said spray dried granules from about 3 to 10%, by weight of the finished composition, of citric acid and effective amounts of perfume and enzymes.

34. A process according to Claim 19 wherein said ratio of alkyl sulfate particles to spray dried granules is between about 30:70 and 10:90, respectively.