【摘要】 采用化学氧化-明胶蛋白接枝法对聚氨酯泡沫塑料(PF)进行表面改性,并用于吸附景观水体中的低浓度氨氮,同时考察了溶液pH值、温度、时间等对吸附的影响。结果表明:作为低成本吸附剂,PF对氨氮具有较好的吸附能力,在平衡浓度为9 mg/L左右时,其吸附量是河砂(RS)的2.06倍。表面改性极大地提高了PF对氨氮的吸附能力,改性物(MPF)对氨氮的吸附能力是活性炭(GAC)的1.45倍,RS的4.56倍。MPF对氨氮的吸附以物理吸附为主,化学吸附极小,吸附速率由表面扩散吸附和颗粒内扩散吸附共同控制,且吸附过程是自发进行的,以熵推动为主;同时,溶液pH值条件对氨氮吸附的影响较小。更多还原

【Abstract】 In this paper, a polyurethane foam(PF) was conducted surface modification by chemical oxidation-gelatin protein grafting, and was used for absorbing low-concentration ammonia nitrogen in landscape water, and meanwhile, the influence of solution pH value, temperature and time on adsorption was also studied. The results revealed that, PF as a low-cost absorbent performed well in adsorbing ammonia nitrogen, and when the equilibrium concentration was about 9 mg/L, its adsorption capacity of ammonia nitrogen was about 2.06 times of that by river sand(RS). The surface modification has greatly improved PF’s adsorption capacity of ammonia nitrogen, and the adsorption capacity by MPF was about 1.45 times than that by activated carbon(GAC), and 4.56 times than that by RS. MPF adsorption of the ammonia nitrogen was mainly physical adsorption while chemical adsorption played only a small part. The adsorption rate was controlled both by the surface diffusion adsorption and the intra-particle diffusion adsorption, and the adsorption was proceeding spontaneously, mainly driven by entropy; in addition, pH value of aqueous solutions had little effect on adsorption of ammonia nitrogen.更多还原