酸碱改性碳吸附脱除黄磷尾气中的H_2S和PH_3

Adsorbing removal of H_2S and PH_3 in off-gas of yellow phosphorus by activated carbon modified through acid and alkali

为综合利用黄磷尾气中的CO,通过钢瓶配气模拟和气相色谱GC-14C测定的方法,研究了酸碱改性碳吸附净化PH3和H2S的相关问题。结果表明:H2S在碱改性碳上平均吸附活化能为23.77 kJ/mol,为负一级吸附反应,PH3在酸改性碳上平均吸附活化能为61.3 kJ/mol,为负二级吸附反应,吸附时以先物理吸附后化学吸附的顺序进行;TG/DTA和孔径分布初步证明吸附质主要为硫和硫氧化物或磷和磷氧化物,酸碱改性碳孔径<1.5 nm的微孔对H2S和PH3的吸附贡献较大,吸附质质量损失主要发生在0—100℃阶段;由机理推导的吸附模型具有很好的可行性。

For the comprehensive utilization of CO in off-gas of yellow phosphorus, chromatography GC-14C and gas stimulation through steel-vase container were used to research adsorbing removal of H：S and PH3 by activated carbon （AC） modified through acid and alkali. The results showed that it was minus first order and 23.77 kJ/mol of average adsorbing activation energy for adsorbing reaction of HES on alkali modified carbon, and minus second order and 61.3 kJ/mol of average adsorbing activation energy for adsorbing reaction of PH3 on acid modified carbon with the order of first physisorption and then chemisorption ; TG/DTA and pore size distribution indicated that main adsorbates were sulfur and sulfur oxides or phosphorus and phosphorus oxides; micropore with radius 〈 1.5 nm made primary contribution for adsorbing removal of H2S and PH3 ; and mass loss of adsorbates occurred mainly in the stage of 0-100℃. A well feasible math model was induced according to mechanism of adsorbing reaction to forecast breakthrough curve.