Patent · US Expired

Process for removing heavy metal ions from wet-processed phosphoric acid

US4452768A · kind A · utility

9Cited by

2References

8Claims

0Family size

Assignee

Hoechst GmbH · DE

Inventors

Reinhard Gradl · Hürth, DE
Gunther Schimmel · Lechenich, DE
Werner Krause · Plantsville, US
Gero Heymer · Lechenich, DE

Key dates

Filing date	Jan 3, 1983
Grant date	Jun 5, 1984
Priority date	—
Expiry date	Jan 3, 2003

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY02P10/20
WIPO fieldMaterials, metallurgy
WIPO sectorChemistry

Abstract

The disclosure relates to process for removing heavy metal ions, especially cadmium, copper, lead and mercury ions from wet-processed phosphoric acid. To this end, the crude acid is contacted with a mixture consisting of an adsorbent and a diorganyldithiophosphoric acid ester or, after treatment with the ester, the acid is contacted with the adsorbent alone, and the purified phosphoric acid is ultimately separated from the ester and adsorbent.

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