Zhejiang Precious Metal Catalyst Comprehensive Refining and Recycling Project

Zhejiang Precious Metal Catalyst Comprehensive Refining and Recycling Project

I. Company Background

Zhejiang Biotechnology Co., Ltd. specializes in the development and production of precious metal catalysts. By leveraging the strong R&D capabilities of Zhejiang University of Technology, the company has created unique solvent-free catalysts known for their support of multiple reuses. To date, we have successfully developed dozens of supported precious metal catalysts. Our main products include palladium carbon, palladium alumina, platinum carbon, platinum alumina, ruthenium carbon, rhodium carbon, and iridium carbon catalysts.

These products serve a wide range of industries, such as pharmaceuticals, pesticides, dyes, fragrances, and liquid crystals. They are primarily used in the catalytic organic synthesis of fine chemicals and in exhaust gas treatment. In addition, the company is licensed to recycle hazardous waste containing precious metals, including spent platinum-group metal catalysts, as well as waste catalysts containing silver, gold, and ternary catalytic materials.

II. Project Overview

Project Name: Zhejiang Precious Metal Catalyst Comprehensive Recycling Project
Raw Materials: Crude platinum, palladium, rhodium, iridium, and ruthenium recovered from spent catalysts.

III. Process Principles

• Palladium Refining: The process involves dissolving palladium, precipitating it, forming an ammonia complex, acidifying to reprecipitate, and finally reducing with hydrazine hydrate.

• Platinum Refining: Steps include dissolution, platinum precipitation, and calcination, followed by hydrolysis, filtration, palladium removal, another round of platinum precipitation, and final calcination.

• Ruthenium Recovery: The ruthenium material is first leached and distilled. The resulting vapors are absorbed in a hydrochloric acid-ethanol solution. Ruthenium powder is then precipitated from this solution, followed by calcination and reduction under hydrogen.

• Rhodium Refining: This method involves dissolution, selective precipitation, and formic acid reduction. The product is then calcined and further reduced with hydrogen.

• Iridium Refining: The process begins with alkali fusion to remove impurities, followed by dissolution in aqua regia. After oxidation precipitation, the material is redissolved in aqua regia. Subsequent steps include sulfide impurity removal, oxidation precipitation, calcination reduction, and cooling to obtain iridium oxide powder.