Benzene → Benzenesulfonic Acid

Participants

Reaction Steps

A fifty-fifty (50/50) hexane mixture by volume of polypropyl benzene alkylates was charged to a continuous sulfonation unit. 20% sulfur trioxide (SO3) by weight in sulfuric acid (H2SO4) was charged to the unit. Spent sulfuric acid (H2SO4) was continuously removed in a two phase non-aqueous system leaving a polypropenyl benzene sulfonic acid product containing 7.4% by weight residual sulfuric acid (H2SO4). At this stage, water was added to dilute the residual sulfuric acid (H2SO4) to 85% by weight, including the sulfuric acid (H2SO4) generated from unused sulfur trioxide (SO3). The aqueous phase was separated from the resultant two phase aqueous-organic system, leaving the organic phase containing 0.98% by weight sulfuric acid (H2SO4). Hexane was added to the organic phase followed by addition of Calcium Carbonate (CaCO3). The resulting mixture was treated with SX-5W oil to reduce the viscosity of the sulfonic acid and also make a 30% by weight active product sulfonate. The product mixture was heated at 215° F. to strip the hexane. The hexane-stripped product was filtered to yield a sulfonic acid and oil product mixture containing less than 0.4%* by weight sulfuric acid.

Provenance & Evidence