Removing of Disinfection By-Product Precursors from Surface Water by Using Magnetic Graphene Oxide

The magnetic graphene oxide (MGO) was successfully synthesised by the in situ chemical co-precipitation method with Fe3+, Fe2+ and graphene oxide (GO) in laboratory and, was used as an adsorbent for disinfection by-product (DBP) precursors removing from four natural surface water samples. The results indicate that various DBPs formation significantly decreased by 7–19% to 78–98% for the four samples after MGO treatment and, the treatment process was rapidly reached equilibrium within 20 minutes. The DBP precursors removal efficiency decreased with the increasing pH value from 4 to 10. Hydrophobic compounds (humic acid and fulvic acid) are more sensitive to MGO, whereas hydrophilic and nitrogenous compounds (aromatic proteins) are more insensitive. MGO could be regenerated by using 20% (v/v) ethanol and, the DBP precursors removal efficiency can stay stable after five cycles. These results indicate that MGO can be utilized as a promising adsorbent for the removal of DBP precursors from natural surface water.

本研究在实验室条件下，采用原位化学共沉淀法，以三价铁离子（Fe³+）、二价铁离子（Fe²+）与氧化石墨烯（graphene oxide, GO）为原料，成功合成了磁性氧化石墨烯（magnetic graphene oxide, MGO），并将其作为吸附剂，用于从4份天然地表水样品中去除消毒副产物（disinfection by-product, DBP）前驱体。实验结果表明，经MGO处理后，4份水样的各类消毒副产物生成量显著降低，降幅达7%~19%，最终残留量为初始值的78%~98%，且该吸附过程可在20分钟内快速达到平衡。消毒副产物前驱体的去除效率随pH值从4升高至10逐渐下降。疏水性化合物（腐殖酸与黄腐酸）对MGO的吸附作用更为敏感，而亲水性含氮化合物（芳香族蛋白质）则相对不敏感。采用体积分数20%的乙醇即可实现MGO的再生，且经过5次循环后，其对消毒副产物前驱体的去除效率仍可保持稳定。上述结果表明，MGO可作为一种极具应用前景的吸附剂，用于从天然地表水中去除消毒副产物前驱体。