Recycling of Solid Zinc Phosphating Process Waste

EPA Contract Number: 68D00023
Title: Recycling of Solid Zinc Phosphating Process Waste
Investigators: Waite, Michael D.
Small Business: Chemical Reclamation Technologies
EPA Contact: Manager, SBIR Program
Phase: I
Project Period: August 1, 1990 through February 1, 1991
Project Amount: $47,110
RFA: Small Business Innovation Research (SBIR) - Phase I (1991) RFA Text |  Recipients Lists
Research Category: Hazardous Waste/Remediation , SBIR - Waste , Small Business Innovation Research (SBIR)


A method for recycling zinc phosphating process waste is proposed. About three million pounds of solid chemical waste is generated annually from zinc phosphating in North America. The waste is an inorganic mixed zinc/iron tertiary salt of phosphoric acid. Toxicity levels vary but most wastes contain nickel, chrome, lead, and other toxins in small quantities. The method depends upon continuous removal of iron as the central mechanism of the recovery process. The waste is converted to an aqueous solution of primary zinc phosphate. By adjusting the concentration of various additives, a product equivalent to the original zinc phosphating feed stock may be created. A method of con- version of the separated iron to feffous oxide is also proposed. Both end products have a proven market The proposed process does not generate waste products of its own.

Supplemental Keywords:

RFA, Scientific Discipline, Toxics, Waste, Chemical Engineering, Environmental Chemistry, chemical mixtures, Hazardous Waste, Chemistry and Materials Science, Engineering, Hazardous, 33/50, Environmental Engineering, complex mixtures, hazardous liquid waste, hazardous waste disposal, hazardous waste treatment, chromium & chromium compounds, hazardous waste recycling, industrial waste, chemical waste, lead, metal complexes, recycled waste products, lead & lead compounds, metal recovery, chemical releases, phosphoric acid, zinc phosphating, nickel & nickel compounds, extraction of metals, heavy metals

Progress and Final Reports:

  • Final