Currently, cyclopentyl methyl ether (CPME) is used as a solvent primarily in the pharma industry, where product purity is of paramount importance. Recent tests show that it also has a high selectivity for gold (Au) ions and can substitute for DBC (di-butyl carbitol) in solvent-extraction methods that recover gold from mine tailings and home appliance waste products such as printed-circuit boards. Compared to DBC, CPME is easier to handle because of its lower viscosity. Material cost is also lower than DBC. In addition to its high selectivity as an extractant for gold, CPME acts as a diluent for recovering other metals. CPME itself is easy to recycle and is an environmentally friendly material. Zeon produces industrial quantities of CPME. It is a totally new hydrophobic ether solvent made using Zeon’s unique synthesis.

Benefits Summary

Characteristics: Apply CPME as an extractant for Au(III) in hydrochloric acid media. o Extraction of precious metal ions using CPME from hydrochloric acid media. o Au(III) extraction using CPME reaches equilibrium within 5 minutes. o Au(III) extracted using CPME is more easily recovered than that using DBC and MIBK.

Development Summary

Already in industrial production using Zeon’s proprietary synthesis process.

IP Summary

This technology is supported by 3 US patents.