Document MMQ5o8N1Jg008bd5nYdzGbmGj

HYDROTROPE PRODUCTION (STXS Plant) PROCESS DESCRIPTION STXS UNIT BALTIMORE. MARYLAND Note: Process Description for STS Production The purpose of this unit is to produce a 40 percent aqueous solution of sodium toluene sulfonate by sulfonation of toluene with 100 percent sulfuric acid and neutralization of the sul furic acid with 50 percent caustic. One hundred percent excess toluene is used in the reaction to assure that most of the sul furic acid is consumed, thereby minimizing the Na2S04 formed on neutralization. Sulfonation Section There are two parallel systems with the same function and capacities in the sulfonation section. Each consists of a standard glass-lined reactor, an overhead condenser, and a water separator. The reactants are measured by means of positive displacement meters with automatic shut off valves. The reaction mixture is heated to the boiling point (230F) with steam and held there during the course of the reaction. Water of reaction and toluene are removed overhead as vapors which are con densed. The condensate flows into the separator from which toluene overflows continuously and passes back to the reactor by gravity. The water flows continuously out the bottom and is collected in measuring drums. Heat is applied to the reaction mixture until 80 percent of the water of reaction and all of the water in the sulfuric acid are removed. The reaction mixture is then cooled to 100F and transferred to the neutra1izer. Neutralization Section water is added to the sulfonic acid and toluene in the neutra lizer in order to make a 40 percent aqueous solution of the final product. Heat is evolved, and the temperature increases to 160i*. Fifty percent NaOH is injected into the sulfonic acid for neutralization, and the material is circulated through SAL 0 r 0 C10 <L 8 3 STXS r ' it Page 2 a heater-cooler to hold it at 200F, thereby avoiding vapor ization of the excess toluene. The sulfonate formed separates from the toluene on settling as the bottom layer, which is pumped out to the slurry rundown tank. The intermediate layer, or cuff, is withdraw i to an accumulator for the recovery of any good product and toluene. The top toluene layer is cooled and pumped to storage. The toluene is separated mechanically instead of by distillation to avoid a concentration of ditolyl sulfons in the product which causes insolubility of the product in water. The sulfonate product is returned to the neutralizer and heated to remove any dissolved toluene. The toluene vapor passes overhead and is condensed by direct con tact with a cold water spray. The product is then cooled and pumped to the slurry rundown tank. It is transferred to heated storage after control tests are run. The same operational procedures are used for the production of sodium xylene sulfonate and ammonium xylene sulfonate. For the latter case, ammonium hydroxide is used as the neutralizing agent. Sulfonation R-H + H2SO4 R-SO3H + H20 Sulfonic Acid where R-H is toluene or xylene Neutralization R-SO3H + NaOH R-S03Na + HjO SXS or STS AXS REB-lec 11-26-7.1 i- m U ch < 1 O cc *t---i O'.! <! Q Cl. z 2 '/) oX w u. < x; as e- o co X 71 M OX o 00 ej Cf.3 V) 6- < Ul CO j -- to CO X 6- co CO :< < --- CO -- 0) 1V 1 ^ro 1c 4-1 0 4J 0 ro c r: 0 c <4-1 0 '4- 0 <4-4 73 3 CO 0 CO 3 u CO a> 04 o c c a> oc 01 4"H * ' 7* 0) >4 (J H X 0 0 >1 4-1 s- X 3 73 e fc 4 Of 3 3 c G> w H 0 Cn *o 73 0 0 CO CO < on <n c "3 -4 CJ U C rt \: J H H 0 < c 4J 4-1 i_; Q, "* 4 01 v: (0 a a -J 3 < 3 flj U 3 ro u < ro 33 O 3* (C z c < 0 Vfa. 4-^ 3 o J* W .Q CJ 0) u o c a/ O u-j ro 4J 0 3 zi o O '/) O CJ O c H 4-^ V ij 0> 0 ^1 0. 73 a> fin X X > ^4 tli t-> ns SAL 0C0010255 SUMMARY SHEkT STXS_ PLAXT OPERATION [>AT .TTMORL. MARYIJ\MT) Production (1907) Lb/Lb Product MM Lbs/Year (Actual) 1. Sodium 'lohiene Sulfonate (STS) 1.14 Feedstock Uuage (Standard) Toluene Suituvie Acid (9 9%) Cause:c So ia ( 50V) W .iter 0.53 9.61 0.52 0.9 5 Sodium Xvl one Sulfonate (SXS) 5.99 Feedstock Usage (Standard) Xylene Sulfuric' Acid (99%) Caustic Soda (50%) Water 0.56 0.52 0.44 1.06 3. Ammonium Xvlenc Sulfonate (AXS) 3.41 oedstock Usaqe Xylene Sul f u r i e Ac id A.;ua .Yv.r cn i .i Wat e r (Standard) (99") 0.57 0.56 0. .19 1. oo 9. Uses STS - elerification agent for liquid detergents; anticaking agent for powdered detergents. SXS - CI a rif icat ion agent for 1iquid detergonts. \\s - V l .iv \ ( i e.U ion aqenl 1 Of ) \ <.|U id dot i * r g (: j l s . k !! 11 *- I >' c i/ SAL C00C10286 11