The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 19, 1978
Filed:
Nov. 03, 1977
Michael Cholod, Cornwells Heights, PA (US);
Rohm and Haas Company, Philadelphia, PA (US);
Abstract
In a process for the preparation of acetone cyanohydrin by the reaction of acetone and hydrocyanic acid in the presence of a sodium hydroxide catalyst, the method of removal of corrosion inducing sodium ion during the purification of the crude acetone cyanohydrin, involving the steps of (1) passing a cooled crude acetone cyanohydrin feedstream through a cationic ion exchange resin to remove substantially all of the sodium ion; (2) regenerating exhausted ion exchange resin; (3) acidifying the substantially sodium ion-free crude feedstream to a pH of 1.5-2.0 to stabilize said crude acetone cyanohydrin; (4) feeding the acidified substantially sodium ion-free crude feedstream to a first concentrator; (5) removing overhead, from the first concentrator, unreacted acetone and sending the bottoms from said first concentrator to a second concentrator; and (6) removing purified acetone cyanohydrin as bottoms from the second concentrator and recycling the overhead for further generation of acetone cyanohydrin.