Method for preparing chromium(III) pyridine-2-carboxylate using 2-OP rectification residues

US10703720B2 · kind B2 · utility

Assignee

• YANCHENG INSTITUTE OF TECHNOLOGY · CN

Inventors

• Zhaosheng Cai · Yancheng, CN
• Jinghua Yu · Changchun, CN
• Pan Xu · Beijing, CN
• Jinyu Bian · 安丰镇, CN
• Ge Ding · 安丰镇, CN
• Lili Shen · Qingdao, CN
• Xujuan Huang · 安丰镇, CN
• Zhonglie Yang · 安丰镇, CN
• Yun Chen · Longbeilingcun, CN
• Peng Xu · Guilderland, US

Key dates

• Filing date: Jun 25, 2019
• Grant date: Jul 7, 2020
• Expiry date: Jun 25, 2039

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/10
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A method for preparing chromium(III) pyridine-2-carboxylate using 2-OP rectification residues, including: subjecting the 2-OP rectification residues to in-situ catalytic pyrolysis and vacuum distillation, room-temperature crystallization and separation, recrystallization and dehydration, alkali-catalyzed hydrolysis, acidification and complexation, and separation, washing and drying to prepare a chromium(III) pyridine-2-carboxylate product, of which a yield is greater than 50% of the weight of the 2-OP rectification residues. The acidification and complexation includes: cooling the aqueous solution containing sodium pyridine-2-carboxylate obtained from the alkali-catalyzed hydrolysis to a temperature below 50° C.; adjusting the aqueous solution to pH 3.0-8.5 with 5-50 wt % dilute H2SO4 or 3-30 wt % dilute HCl followed by batchwise addition of CrCl3, Cr(NO3)3 or Cr2(SO4)3 for complexation at 20-70° C. to obtain a slurry containing chromium(III) pyridine-2-carboxylate, which is separated, washed and dried to obtain a chromium(III) pyridine-2-carboxylate product with a purity of 98.5% or more.