Patent · US Expired

Method for sulfonation using porous absorber material

US5233081A · kind A · utility

7Cited by
6References
17Claims
0Family size

Inventor

Key dates

Filing dateMar 30, 1992
Grant dateAug 3, 1993
Priority date
Expiry dateMar 30, 2012

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07B45/06
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A method for preparing a sulfonated compound with minimal or no waste products using a porous inorganic material absorber. The absorber is saturated with a compound to be sulfonated and then contacted with a sulfonating gas mixture to form a sulfonated product. After forming the sulfonated product, excess sulfonating gas is removed by contacting the sulfonated product with warm air. The sulfonated product is then neutralized and the product is removed with water from the inorganic material absorber. The absorber is then dried with hot air so that it may be reused for future sulfonation processes. The process results in preparation of a sulfonated compound having inorganic salts present in an amount less than about 1.0 percent by weight based on total sulfonated product weight. The process results in highly effective sulfonation of a compound with formation of little or no waste materials, particularly waste materials such as solvents and undesirable inorganic salts. Also disclosed is the resulting sulfonated product.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.