Process for producing tartaric acid from a raw material containing potassium hydrogentartrate

US6534678B1 · kind B1 · utility

Assignees

• Metallgesellschaft AG · DE
• Spezial Chemie Leuna GmbH & Co. KG · DE

Inventors

• Rudolf Bönsch · Nackenheim, DE
• Dieter Stein
• Klaus Erb · Mittelbiberach, DE

Key dates

• Filing date: May 3, 1999
• Grant date: Mar 18, 2003
• Expiry date: May 3, 2019

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/487
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Process for producing tartaric acid from a raw material whose dry matter comprises at least 5 wt% potassium hydrogentartrate wherein the raw material containing potassium hydrogen tartrate (KHT) is mixed with aqueous potassium hydroxide solution in a first reaction stage, where KHT is virtually completely reacted to form dipotassium tartrate (DKT), the aqueous solution containing DKT is then mixed with added acid in a precipitation stage at a pH value of 2.0 to 5.0, to produce a suspension containing crystallized KHT; crystallized KHT is then separated from the suspension, washed with water, and there is produced a solution at least 80 wt-% saturated with KHT and then the potassium is removed, to obtain an aqueous tartaric acid product solution, from which water is then at least partly removed.