SO3 utilization

The lead-chamber process supplied the world s need for sulfuric acid for a century and a half. In the late nineteenth century, the contact process replaced the lead-chamber process. The contact process utilized sulfur dioxide, SOj, which was produced as a byproduct when sulfur-bearing ores were smelted. The contact process was named because the conversion of sulfur dioxide to sulfur trioxide, SO3, takes place on contact with a vanadium or platinum catalyst during the series of reactions ... 

Batch processes are currently used for the manufacture of small volume specialty sulfonates based on H2S04, oleum, CISO3H, sulfite, or SO3 reagents. Production of large volume sulfonates or alcohol sulfates generally utilize continuous S03 falling-film processes based on multitubular or concentric designed reactor systems. 

The vast majority of sulfonic acids were produced using continuous falling film sulfonation technology, which utilizes vaporized SO3 mixed w ith air. This technology dominates the sulfonation industry owing to the capability of high product throughput and low by-product waste streams. 

Photolysis of alkane/S02 mixtures leads to the formation of alkylsulfonic acids,the Hostapon process utilizing SOdOilhvP It is curious that this reaction seems to be so efficient, given the low e for alkane and SO2 at the wavelengths used, and an efficient chain reaction is presumably involved. The Reed reaction uses SO2/CI2/I11 to convert alkanes to the corresponding sulfonyl chlorides. Alkanes also react with SO3 to give alkyl sulfonates, sulfones and sulfates. ... 

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