High-performance liquid-phase catalytic purification of phosphine in tail gas using Pd(II)/Cu(II) composite

Abstract

Pd/Cu liquid-phase composite was utilized as the catalyst in this study to remove PH3 at low temperatures. The anti-heterotoxicity of catalysts in the PH3 catalytic oxidation purification process was carefully explored and pioneered. The catalytic performance, thermodynamics, kinetics, and catalytic oxidation mechanism of Pd/Cu liquid-phase catalyst catalytic oxidation of PH3 were thoroughly investigated. The results showed that Pd/Cu has a superior catalytic effect on the removal of PH3 in the gas mixture under low temperature. With CO as the carrier gas, the removal efficiency of PH3 could be maintained at 100% for nearly 450 min, indicating that the Pd/Cu liquid phase catalyst has good resistance to heterotoxicity. According to the thermodynamic, kinetic, and related characterization results of the PH3 purification process, the kinetic region of the gas–liquid reaction of PH3 absorption by Pd/Cu solution was an interfacial reaction. Pd was the primary catalyst and Cu was the secondary catalyst, and the adsorption of PH3 was a primary reaction. PH3 was spontaneously oxidized to H3PO4 in the Pd/Cu catalytic system during the removal process. Pd was regenerated by O2 and Cu, increasing the activity and stability of the Pd/Cu catalyst in the sustain and efficient purification of PH3 in tail gas.