Course: Chemical Technology (Organic)
Module IV
Lecture 2
Synthetic Detergent And Linear Alyl Alyl !en"ene
L#CT$%# 2 S&'T#TIC D#T#%#'T A'D LI'#A% AL*&L !#'+#'# D#T#%#'T A detergent is a surfactant or a mixture of surfactants having cleaning properties in dilute solutions. Commonly, "detergent" refers to alkylbenzenesulfonates, a family of compounds that are similar to soap but are less affected by hard water. •
High detergency in soft and hard water they do not react with Ca and !g solution.
•
#e$uirement of small $uantity
•
%etergency action at low temperature
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%o not hydrolyses
Ta,le M-IV 2./: Ty0es o1 S0ecialty Sur1actants Anionic &ther carboxylates Acylisethionates )hosphate esters *arcosinates *ulfosuccinates +aurates
Am0hoteric Amphoteric acetates (etaines and siltaines
Cationic Amine 'xide
'onionic Alkyl polyglucosides
*ource Chemical -eekly ovember /0, )1/22, /233.
%uring 425s and 625s the detergent market was primarily captured by the dodecyl benzene %%(, a product formed by alkylation of (enzene with propylene tetramer in a hard detergent alkylation unit. 7t was found, however, that the branched structure of the alkyl group was responsible for the poor biodegradability of the detergent, and the linear alkyl (enzene 8A( was introduced in the early 925s have substantially replaced its counter parts. Although 8inear alkyl benzene is the ma:or detergent being used due its low cost as derived from petroleum feed, other surfactants used widely are fatty alcohol sulphates;A*, ;atty alcohol ether sulphates<;&*, fatty alcohol ethoxylates A&.
atty Alcohols +here has been rapid growth in the use of fatty alcohols due its low toxilogical profile and safe use, continued substitution of soap by alcohol based surfactants in the personal care industry, 145
strong sales of laundary li$uids that use higher levels of alcohol based surfactants, displacement of 8A* surfactants by alcohol based surfactants, the substitution of alkyl phenol eythoxylates by alcohol based surfactants< (rent, /224=.the global market for fatty alcohol has shown significant growth. 'leochemical route to alcohols starting from vegetable>animal oils and fats has dominant share?2@ of global capacity of about . million tones synthetic alcohol produced from petrochemically derived ethylene still continues to have a about 2@ share < Chemical weekly, ovember /0,/233, p.30?=
CLASSIICATIO' O D#T#%#'T 3http>>www.princeton.edu>Bachaney>t mve>wiki322k>docs>%etergent.html4 A'IO'IC D#T#%#'TS:
+he detergency of the anionic detergent is vested in the anion. +he anion is neutralized with an alkaline or basic material, to produce full detergency <iwi -eb=. +ypical anionic detergents are alkylbenzenesulfonates. +here are three kinds of anionic detergents a branched sodium dodecylbenzenesulfonate, linear sodium dodecylbenzenesulfonate, and soap. +he alkylbenzene portion of these anions is lipophilic and the sulfonate is hydrophilic. +wo varieties have been popularized, those with branched alkyl groups and those with linear alkyl groups. <*mulders et al., /22/=.
CATIO'IC D#T#%#'TS:
+he detergency is in the cation, which can be a substantially sized molecule. *trong acids are used, such as hydrochloric acid to produce the C7 anion as the neutralizing agent although in essence, no neutralization takes place in the manufacturing process <iwi -eb=. Cationic detergents are similar to the anionic ones, with a hydrophobic component, but instead of the anionic sulfonate group, the cationic surfactants have $uaternary ammonium as the polar end. +he ammonium center is positively charged. <*mulders et al., /22/=.
#TO5&LAT#S: &thoxylates are compounds that have long hydrocarbon chains, but
terminate with 'CH/CH/n'H group. +hese groups are not charged, but they are highly hydrophilic owing to the presence of many oxygen centres.
'O'-IO'IC O% +6ITT#%IO'IC D#T#%#'TS: +his detergent consists of no inonic
constituents which are ionically inert. +he vast ma:ority of all non1ionic detergents are condensation products or ethylene oxide with a hydrophobe. +his grop of detergents is enormous, and the permutation endless. +hese are char acterized by their net uncharged, hydrophilic head groups. +hey are based on polyoxyethylene i.e. +ween, +riton and (ri: series, Chaps, glycosides i.e. octyl1thioglucoside, maltosides, bile acids such as %'C, lipids H&DAs, or phosphine oxides. Ewitterionic detergents possess a net zero charge arising from the presence of e$ual numbers of F3 and 13 charged chemical groups.
!ASIC COM7O'#'TS O D#T#%#'T •
%etergent 8inear alkyl benzene sulphonate
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(uilders )hosphate *odium tripolyphosphate boost detergent powder, citrates, silicates, carbonates, zeolite
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;ilters and )rocessing Aids *odium carbonate, sodium sulphonate
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Corrosion inhibitors *odium silicate
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Anti redeposition agent Carboxy methyl cellulose
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;abric (rightners ;luoroscent dyes
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(luing 7mprove whiteners by counteracting natural yellowing tendency
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Antimicrobiol agents Carbinilides, salicylanilides
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&nzymes %ecompose or alter the composition of soil and render the particles more easily removable.
*ome of the enzymes used in detergent are protease,amlases,liapse and celolases. +he enzymes catalyses the breakdown of chemicalds through addition of water and helps in the removal of soils.<*aini,/223a=.)olymers and enzymes play important role in improving the detergency. )olymers help in soil removal, prevent insoluble salt incrustation work as anti1soil re1deposition, inhibit dye transfer. Gse of optical brightner enhance the brightness and whiteness. processing aids when added to slurries of detergent powder improve stability and homogeneity of slurries during mixing and reduce viscosity<*aini, /223b=.
LI'#A% AL*&L !#'+#'# 8A( basic raw material for detergent which was introduced in 92 s as substitute for non1 biodegradable branched. 'ther surfactants are alcoholsulphate A*, alcoholethoxylates A&, *econdary alkane sulphonate, and alpha olefin sulphonates. 8A( is a clear colourless li$uid with characteristic odour. 7t is most widely used as the basic raw material for the manufacture of synthetic detergent. +he linear alkyl (enzene produced from the C32 I C3 or C33 I C34 linear mono olefins are useful detergent intermediate and can be readily sulphonated to yield linear alkyl benzene sulphonates. +hese compounds constitute the JactiveK ingredients of many house hold detergents. +hey are surface active compounds surfactants which are combined with various builders often inorganic salts to make up a detergent formula. 8inear alkyl benzene 8A( is the basic raw material for production of most widely used detergent. 8inear alkyl benzene was introduced as substitute for non biodegradable branched alkyl benzene. )rocess involved for 8A( manufacturing is mention in +able !17L /.. Although 8A( demand grew by 34@ per annum during 30M4102, future demand in the country is pro:ected to increase at a healthy growth rate of ?1M@ as against /14@ worldwide. 7ndia and China with huge population are the largest market for 8A( 8A( manufactured in 7ndia started in 30M6 by 7)C8 in 30M6 followed by #eliance 7ndustries, +amilnadu )etro products, irma, 7'C. Application of 8A( in 7ndia is mention in +able !17L /./. N
7)C8., Ladodara
62,222 +)A
N
#eliance 7ndustries )atal ganga
3,22,222 +)A
N
+amil adu )etro )roducts
3,/2,222 +)A
N
irma 8imited
?6,222 +)A
N
7ndian 'il Corporation, vadodara
3,/2,222 +)A +otal 4,96,222
Ta,le M-IV 2.2: LA! A00lication in India Application Consumer Cleaning )roducts a. *ynthetic detergents for fabric wash )opular !id1)rice )remium b. *couring products
*hare @ 09./ 02.3 9M. 3. 3M.4 M.?
c. 8i$uid detergents 7ndustrial O 7nstitutional Cleaners 'ther 7ndustrial Application on1surfactant Applications varnish, cable fluid oil, lubricant +otal
3./ 3. /.6 2.3 322
*ource 7ndian 'il Corporation,Chemical -eekly ovember /0, )1300, /233.
Ta,le M-IV 2.8: 7rocess ste0s in LA! manu1acture 7re1ractionation
To o,tain C/9-C/ range hydrocar,ons 1rom erosene. (n-C/9 to nC/8 1or light and n-C//to n-C/ 1or hea;y LA!). +he 8A( unit re$uires a very specific feed in terms of carbon number. +he prefractionation unit is designed to process a high purity C0 to C36
linear normal paraffin feed and to separate out a heart cut with the desired carbon number which will range from n C32 to n3 for light 8A( and nc33 I nc34 for heavy 8A(. ydrotreator
To remo;e sul0hur com0ounds 1rom 1eed stoc +he purpose of this unit is to remove sulfur and nitrogen from the feed without greatly changing its (.). 7f not removed, sulfur and nitrogen would poison the sieve in the !olex Gnit.
7ara11in Se0aration (7are< 0rocess)
+o remove n1paraffins from kerosene by selective adsorption using molecular sieve. +he G') !'8&P process is an effective method of continuously separating normal paraffins from a stream of co1 boiling hydrocarbons by means of physically selective adsorption. +he feed stock is separated into a high purity normal paraffin fraction at high recoveries and a non1normal paraffin. Dehydrogenation o1 n-0ara11ins to ole1ins. +his process dehydrogenates the high purity linear paraffin feed stock from the pre1fractionation unit into the corresponding non1olefins, suitable as feed stock for the down stream detergent alkylate unit.
Dehydrogenation o1 7ara11ins (7acol 7rocess) Alylation
Alylation o1 ,en"ene =ith ole1ins to o,tain LA! in 0resence o1 or solid "eolite catalyst +his process alkylates benzene with linear olefins produced by the )acol unit in the presence of H; acid catalyst to yield linear alkyl benzenes, 8A(. +he 8A( thus produced can be readily sulfonated to form a suitable ingredient for many household detergents. +his unit consists of three processing section i. Alkylation *ection ii. ;ractionation *ection iii. Acid #egeneration *ection
n o i t a n o i t c s a n r 1 e m r l u 7 o C
n o i t a n o i t c s a n r 1 e m r l u 7 o C
igure M-IV 2./: 7re-1ractionation 7re-Treatment and 7ara11in Se0aration
Alylation $nit
LA! Sul0honation
igure M-IV 2.2: Manu1acture o1 linear alyl !en"ene Sul0onate
LA! !& SOLID ACID CATAL&ST +he conventional catalyst AlCl, H/*'4 and H; commercially used has the disadvantage of causing corrosion of e$uipment as well as waste production. +here has been continuous search for development of non corrosive solid catalyst with similar catalytic properties. *ome of the catalyst which have been developed are *i'/1Al/', H1,ontmorillonite, amberlyst, H1Q, H1 (eta, H!
igure M-IV 2.8: LA! Manu1acture 1rom i
151
MA'$ACT$%I' O D#T#%#'TS %etergents use a synthetic surfactant in place of the metal fatty acid salts used in soaps. +hey are made both in powder and li$uid form. !ost detergents have soap in their mixture of ingredients, but it usually functions more as a foam depressant than as a surfactant. Larious processes in manufacturing of detergents is mention in +able !17L /.4.
A synthetic detergent, a sodium alkyl sulfate called sodium dodecylsulfate, will be prepared by reacting dodecyl alcohol dodecanol with sulfuric acid.
+he resulting dodecylsulfate is converted to the sodium salt by a reaction with sodium hydroxide.
Ta,le M-IV 2.: Various 7rocesses 1or Maing Detergent 7o=der Detergent *lurry making +he solid and li$uid raw ingredientsare dropped into a large tank known as a slurry mixer. As the ingredients are added the mixture heats up as a result of two exothermic reactions the hydration of sodium tripolyphosphate and the reaction between caustic soda and linear alkylbenzenesulphonic acid. +he mixture is then further heated to M6oC and stirred until it forms a homogeneous slurry. *pray drying +he slurry is deaerated in a vacuum chamber and then separated by an atomiser o into finely divided droplets. +hese are sprayed into a column of air at 4/6 C, where they dry instantaneously. +he resultant powder is known as 5base powder5, and its exact treatment from this point on depends on the product being made. )ost dosing 'ther ingredients are now added, and the air blown through the mixture in a fluidiser to mix them into a homogeneous powder. +ypical ingredients are
*oda ash anhydrous a/C', (leach usually sodium perborate. a(', (leach activator e.g. tetraacetylethylenediamine, &nzymes e.g. alkaline protease, Colour and perfume Li>uid Detergent *oap premix 8i$uid detergent contains soap as well as synthetic surfactants. +his is usually manufacture made first as a premix, then other ingredients are blended into it. +his step simply consists of neutralizing fatty acids rather than fats themselves with either caustic soda a'H or potassium hydroxide. 7ngredient All ingredients except enzymes are added and mixed at high temperature. +he mixing ingredients used in the li$uid detergent manufacture are typically sodium tripolyphosphate, caustic soda, sulphonic acid, perfume and water. +he functions of these ingredients have been covered above. &nzyme +he mixture is cooled and milled, and the enzymes added in powder form. addition
%##%#'C# 3. Almeida, 3004 2.
*aini,*.. J *ynyhetic detergent powders changing trends part 7 J chemical weekly !arch,/2,/223a,p.340
3.
*aini,*.. J *ynthetic detergent powders changing trends part 77 J chemical weekly !arch,/?,/223b,p.343
4. (rackmann,(., %eutschland,C, Hager,Claus1%ierk, J Lersatility of derived surfactants will propel demand for fatty alcoholsK Chemical weekly August /4, /224,p366. 6. #enaud,). (rackmann,( J atural based fatty alcoholsK Chemical weekly August /4, /224,p366. 9. *mulders &., #ybinski -., *ung &., #Rhse -., *teber S., -iebel ;., ordskog A., "8aundry %etergents" in Gllmann5s &ncyclopedia of 7ndustrial Chemistry /22/, -iley1LCH, -einheim ?. http>>www.princeton.edu>Bachaney>tmve>wiki322k>docs>%etergent.html M. http>>www.chemistry.co.nz>detergentTclass.htm 0. Chemical weekly, ovember /0,/233, p.30? 32. Chemical -eekly ovember /0, )1/22, /233. 11.
7ndian 'il Corporation, Chemical -eekly ovember /0, )1300, /233.
