Anionic surfactants secondary alkanes sulfonates and alpha-olefin sulfonates

Secondary Alkane Sulfonate (SAS)

Anionic surfactantSecondAlkanesSulfonates are newer commercial surfactants. By the action of sulfur dioxide and airC12~C14‘s positiveAlkanesPreparedObtained.

This reaction is obviously different from sulfonation and esterification with sulfuric acid, and is called oxysulfonation. The overall balanced formula of the reaction is as follows:

R CH2R+2SO2+O2-H2O— K-CH-R-H2SO₄

SO2H

During the reaction, sulfonic acid groups can appear in straight chainsalkanesAny position on the base. After oxysulfonation, it is similar to the production of LAS and is directly dried and dried.

SAS has similar foaming and washing properties to LAS, and has good water solubility. SAS is currently only produced in Western Europe, and its main purpose is to compound it into liquid washing agents, such as liquid household dishwashing detergents. This process was first developed by the West German company Hester, with the brand name HasiapmSAS6. Xuan products contain 60% active ingredients. The disadvantage of SAS is that the laundry detergent using it as the main component is sticky and not loose. Therefore, only used in liquid formulations.

Alpha-eneHydrocarbonsSulfonic acidSalt (AOS)

α–AlkenesHydrocarbons are produced by paraffin oil cracking or Zilleg ethylene oligomerization Prepared, obtained after rough separationC1 2~ C18α–enehydrocarbon. It is produced by sulfonating sulfur trioxide diluted with air and then neutralizing it. The reaction process is more complex, producing a mixture of multiple compounds. In the first step, about 40% of enehydrocarbonsSulfonic acid and 60% of 1.3- and 1,4-eneHydrocarbonSulfonic acidlactone.

The sultone in the sulfonation product is further hydrolyzed by the aqueous sodium hydroxide solution and neutralized at the same time, and the hydroxyl group in the obtained productAlkanesSulfonates andAlkeneHydrocarbonThe ratio of sulfonate (AOS) is about 2:1 . In the hydrolyzed product, there are about 60% alkenesulfonates and 40% hydroxyl alkanesSulfonic acidSalt.

Generally speaking, the performance of AOS and LAS are similar, but AOS is harmful to the skin. It is slightly less irritating and biochemically degrades slightly faster. Due to its simple production process and low cost of raw materials, AOS has always been very attractive. In the past, there were certain difficulties in controlling the production process. In recent years, improvements in equipment have basically solved this problem. Since 1980, the production and application of AOS have been on the rise. The main use of AOS is in the preparation of liquid detergents and cosmetics.