Removal of P_4, PH_3 and H_2S from Yellow Phosphoric Tail Gas by a Catalytic Oxidation Process

Yellow phosphorus tail gas is a resource used to produce bulk chemicals, such as formates, oxalates, and methanol after its pretreatment and purification. In this study, catalytic oxidation of phosphorus and hydrogen sulfide in yellow phosphorus tail gas was investigated on an ordinary activated carbon (OAC) and a home made catalyst KU2. The adsorption characteristics of phosphorus and hydrogen sulfide on the catalysts were studied in a fixed-bed system at different temperatures between 20℃ and 140℃ at atmospheric pressure. Both KU2 and OAC are proved to be effective catalysts in the catalytic oxidation process (COP) for H 2S and PH 3 removal. Purification efficiency increased with the increase of temperature and oxygen concentration in yellow phosphorus tail gases. Under optimized operation conditions, the product gases with a content of hydrogen sulfide<5 mg/m 3 and total phosphorus<5 mg/m 3 were obtained by using the COP process. Deactivated catalysts could be restored to the original activated state, even after several regenerations. A mathematical model was developed to simulate the experimental results and the mass transport coefficient from the experiment was evaluated. Good agreement between the experimental breakthrough curves and the model predictions was observed.

俄国海军的美利坚明珠 “瓦良格”号防护巡洋舰

远东的需要 说起“瓦良格”号的诞生，还要从中日甲午战争说起。在1894-1895年的甲午战争中惨败后，大清帝国割让辽东半岛（包括旅顺港）给日本，这个特许权引起欧洲国家的骚动。之后，俄国、法国、德国组成“三国干涉”：警告日本将辽东半岛归还中国；给予韩国独立地位。此时的日本还没有能力对抗这三个欧洲大国中的任意一个，更不要说三国联盟，因此只有黯然退让土地。