Process for high purity tetrabromobisphenol-A
AssigneeEthyl Corporation
InventorsBonnie G. McKinnie, Gary L. Sharp
Life of this patent
Estimating the term…
Abstract
The quality of a product predominant in tetrabromobisphenol-A is enhanced by contacting the product with a quality enhancing amount of treated water and heat treating the product for a period of time and at a temperature which are sufficient to obtain a TBBPA predominant product having less than about 20 ppm of ionic impurities.
Claims19
An improvement in a process for enhancing the quality of a flame retardant product predominant in tetrabromobisphenol-A (TBBPA), wherein the improvement comprises (a) contacting said product with an amount of treated water, which treated water has a resistivity of greater than about 50,000 ohms and (b) heat treating said product for a period of time and a temperature which are sufficient to obtain a TBBPA predominant product having less than about 20 ppm of total ionic impurity wherein the amount of treated water is more than about 0.2 grams per gram of product so contacted and wherein the ionic impurity is predominantly HBr.
A flame retardant composition comprising a product predominant in tetrabromobisphenol-A and containing less than about 10 ppm ionic impurity and less than about 2.0 percent organic impurity.
A process for preparing a flame retardant product predominant in tetrabromobisphenol-A comprising:
- a) brominating bisphenol-A with bromine at a temperature in the range of from about 0.degree. C. to about 100.degree. C. in a solvent comprising methanol and from about 3 to about 15 wt. % water;
- b) collecting the brominated bisphenol-A product as a solid;
- c) contacting the solid product with an amount of treated water, which treated water has a resistivity of greater than about 50,000 ohms;
- and
- d) heat treating the contacted solid at a temperature and for a period of time, which time and temperature are sufficient to form a product predominant in tetrabromobisphenol-A having less than about 20 ppm total ionic impurity wherein the amount of treated water is more than about 0.2 grams per gram of solid product so contacted and wherein the ionic impurity is predominantly HBr.
Dependencies are inferred from the claim text.