Purification of yellow phosphorus tail gas for the removal of PH3 on the spot with flower-shaped CuO/AC

Abstract

The process of PH₃ adsorption removal for purifying yellow phosphorus tail gas on the spot with flower-shaped CuO was investigated in this study. Flower-shaped and irregular-shaped CuO/AC adsorbents were prepared by hydrothermal and impregnation methods, respectively. They can effectively remove PH₃ less than 1 mg m⁻³ and the purification efficiency is nearly 100% without fluctuation. However, the morphology of CuO on the adsorbent surface plays an important role in phosphine adsorption. The breakthrough adsorption capacity of the flower-shaped CuO adsorbent was 96.08 mg(PH₃)/g(adsorbent), which was 2.23 times that for irregular-shaped CuO. The purification efficiency of the flower-shaped CuO was also influenced by temperature, oxygen volume fraction and space velocity. At a temperature of 100 °C and an oxygen volume fraction of 1.6%, the adsorption capacity is the best. The adsorbent can be renewed and the regenerated catalyst can also efficiently remove PH₃ with a purification efficiency of nearly 100%. In the process of catalytic oxidation, according to XPS, we can conclude that CuO plays a very important role in phosphine adsorption and that oxygen is able to accelerate the oxidation of PH₃ and oxidize Cu to regenerate the active species in the process of purification.