Patent · US Expired

Byproduct recovery from a pentaerythritol waste stream

US4277620A · kind A · utility

4Cited by
6References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 29, 1980
Grant dateJul 7, 1981
Priority date
Expiry dateFeb 29, 2000

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C51/42
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

This invention provides a process for recovery of sodium formate from an aqueous waste stream which is a byproduct mother liquor derived from a reaction system in which pentaerythritol is produced by the reaction of formaldehyde with acetaldehyde in the presence of metal hydroxide catalyst. Among its important features, the invention process involves evaporative crystallization of the mother liquor to separate out a major proportion of metal formate; dilution of the resultant secondary aqueous waste stream with methanol to precipitate metal formate/pentaerythritol solids; contact of the solids with a portion of the primary aqueous waste stream feed to dissolve metal formate; and recycle of the metal formate-enriched aqueous stream to the evaporative crystallization step of the process.

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