Catalytic Oxidation of Phosphine by Aqueous Copper–Ammonia Complexes

The furnace gas resulting from the electrothermal production of yellow phosphorus contains up to 95% CO, 2% O2, 2% H2, and 0.3–4.0% impurities, including phosphine (PH3), yellow phosphorus (P4), and hydrogen sulphide (H2S), which are characterized by flammability, explosion hazardousness, corrosiveness, and high toxicity. The presence of toxic impurities does not allow the use of waste gases from phosphorus production, which are mainly composed of valuable carbon monoxide, as chemical raw materials and/or process fuel. The authors propose a method for the purification of furnace gas from the main toxic component, phosphine, by its oxidisation using aqueous copper–ammonia complexes as a catalyst. This approach allows the cleaning process to be conducted under mild conditions. The degree of purification of the model furnace gas from P components is 90–99%, depending on the process conditions.