尿素、丙烯酸改性酚醛泡沫脱除烟气中的SO_2和NO

SO_2/NO removal by urea and acrylic modified phenolic foam

酚醛泡沫价格低廉制造方便,拥有可灵活控制的孔径及能够嫁接目标官能团的特点,是一种可用于烟气脱硫脱硝的优异新型吸附材料。选用尿素和丙烯酸对酚醛泡沫前驱体进行改性,研究改性后酚醛泡沫的表面结构变化及对脱除SO_2/NO的影响。结果表明,尿素和丙烯酸与树脂发生化学反应,在发泡成型后成功负载C—O、酚羟基、C—N、—NH和—CONH_2等有利于脱除酸性气体的活性基团。同时,改性后酚醛泡沫的比表面积和总孔容增大,孔径主要分布在中孔范围,孔壁上分布数量不等的小孔。这些改性后形成的物理化学结构提高了酚醛泡沫脱除SO_2/NO效率,脱除效果最好的复配改性样品为PF5(140 g苯酚中,加尿素20.0 g、丙烯酸23.0 g),在模拟无水烟气时,其稳态脱SO_2/NO效率分别达61.8%和21.75%。

Phenolic foam is an effective material for desulfurization and denitrification of flue gas because of its low manufacturing costs and adjustable pore size,and because it can be easily grafted with different functional groups. In this work,urea and acrylic acid as precursor modifiers were applied to modify phenolic foam. The surface structures and SO2/NO removal effectiveness of the modified phenolic foam were investigated in this study.The results indicated that high surface area of mesoporous was observed in the modified phenolic foam. The functional groups,including C—O,phenolic hydroxyl,C—N,—NH,and —CONH2,were successfully grafted onto the surface of the modified phenolic foam. In addition,the SO2/NO removal efficiency was greatly improved by the formed physical and chemical structures. When simulating the case of dry flue gas,the highest SO2 and NO removal efficiencies were 61. 8% and 21. 75%,respectively,by sample PF5,which was prepared from 140 g of phenol,20 g of urea,and 23 g of acrylic acid.