Process for preparation of a polissacarideo modified aqueous compositions of polissacarideos modified; and polissacarideo modified in Po.

摘要

Novel deacetylated polysaccharide biopolymers having improved viscosity/filtrability/injectability, well adopted for the secondary and tertiary recovery of oil deposits, are conveniently prepared by (i) acidifying an aqueous polysaccharide composition, e.g., a carbohydrate fermentation broth, with nitric acid to a pH of from about 2 to 0.1, (ii) heat-treating said acidified composition at a temperature of from about 50 DEG to 100 DEG C. for from about 5 to 60 minutes, and (iii) cooling said heat-treated composition and adjusting the pH thereof to a value of from about 5 to 7.