State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
Institute for the Advanced Study of Sustainability, United Nations University, Jingumae 5-53-70, Shibuya-ku, Tokyo 150-8925, Japan.
J Hazard Mater. 2022 Aug 15;436:129098. doi: 10.1016/j.jhazmat.2022.129098. Epub 2022 May 7.
In this study, a novel adsorbent of graphene oxide (GO) incorporated ferrihydrite (FH) was fabricated and integrated with ultrafiltration (UF) to remove natural organic matter (NOM), the crucial cause of membrane fouling and major precursor of disinfection by-products (DBPs). Compared with FH and powdered activated carbon (PAC), GO/FH exhibited superior removal for high molecular weight (HMW) humic- and fulvic-like substances and low molecular weight (LMW) protein. The cake layer formed by GO/FH alleviated the deposition of NOM on membrane surface or inside membrane pores. Therefore, GO/FH reduced 89% and 95% total fouling resistance and irreversible membrane resistance, respectively, together with the lowest increment of transmembrane pressure. Pearson correlation analysis indicated that DOC, rather than specific ultraviolet absorbance (SUVA) and UV, was significantly correlated to the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) when SUVA was below 4 L/mg-C.m. Whilst the HMW NOM (1-20 kDa) was highly related to dibromochloromethane (DBCM) (r = 0.98-1), the LMW fraction (< 1 kDa) was correlated with dibromochloromethane (TCAA) and dichloroacetic acid (DCAA) (r = 0.88-0.98). Inspiringly, GO/FH-UF reduced 90% of carbonaceous DBPs, the concentrations of which well met the WHO Guidelines. In summary, GO/FH-UF substantially alleviated membrane fouling and dramatically reduced DBP formation potential.
在这项研究中，制备了一种新型氧化石墨烯（GO）负载水铁矿（FH）吸附剂，并将其与超滤（UF）集成以去除天然有机物（NOM），NOM 是膜污染的关键原因，也是消毒副产物（DBPs）的主要前体。与 FH 和粉末活性炭（PAC）相比，GO/FH 对高分子量（HMW）腐殖质和富里酸类物质以及低分子量（LMW）蛋白具有更好的去除效果。GO/FH 形成的滤饼层减轻了 NOM 在膜表面或膜孔内的沉积。因此，GO/FH 分别降低了总过滤阻力和不可逆膜阻力 89%和 95%，同时跨膜压力的增加最小。Pearson 相关分析表明，DOC 与三卤甲烷（THMs）和卤乙酸（HAAs）的生成显著相关，而当 SUVA 低于 4 L/mg-C.m 时，特定紫外吸光度（SUVA）和 UV 则没有明显相关性。高分子量 NOM（1-20 kDa）与一溴二氯甲烷（DBCM）高度相关（r = 0.98-1），而低分子量部分（<1 kDa）与一溴二氯甲烷（TCAA）和二氯乙酸（DCAA）相关（r = 0.88-0.98）。令人鼓舞的是，GO/FH-UF 降低了 90%的碳基 DBPs，其浓度符合世界卫生组织（WHO）指南。综上所述，GO/FH-UF 可显著减轻膜污染并极大降低 DBPs 的生成潜力。
