Dialkylbenzene sulphonate

Hausler and Taylor [7] used 100 A /i-Styragel with toluene as eluent (0.5-1.0mLmin ) to separate metal salts of dialkylbenzene sulphonates in a petroleum-based matrix. A specially-designed nebulizer was used for ICP-AES detection. A mixture of four ferrocenes was clearly separated into four peaks, in the elution order bis(tetrapyrazolylborate) iron, 1, I -diacetylferrocene, acetylferrocene and ferrocene. Metal detection limits were similar to those obtained with aqueous samples. 

Due to their high molecular weights, these compounds are easily removed by distillation. There is a market for the dialkylbenzenes which can be sulphonated to produce synthetic petroleum sulphonates. 

The high molecular weight fractions from LAB manufacture can also be used as raw materials for petroleum sulphonates. The preferred feed is the dialkylbenzene which can give products of similar performance to a custom-made C20+ alkylbenzene. The alkylate still bottoms (as these materials are often called) also contain diphenyl alkanes. When sulphonated, these become highly water soluble and should be removed, either by distillation of the organic feed, or separation from the oil soluble sulphonates. 

---