Abstract:
Lead(II) is a potential carcinogen of heavy-metal ions (HIs). With the wide application of Pb-bearing products including lead alloy products, and new-energy lead-ion batteries, lead pollution has become a tricky problem. To solve such a difficulty, novel ultrathin MoS2-vinyl hybrid membranes (MVHMs) with a \"spring\" effect were synthesized via co-polymerization of acrylic acid, styrene and molybdenum disulfide (MoS2) and their adsorptions for HIs were explored. The \"spring\" effect derived from the interaction between the tendency of the short polyacrylic acid (PAA) chain connected with MoS2 to spread outward and the coulomb force between layers from MoS2 (s-MoS2), which enlarge the spacing of MoS2 layers without changing the number of layers after membrane formation, which changes the swelling membrane to a dense membrane and reduces the original thickness from 0.5 cm to 0.011 mm in the thickness direction. The adsorption experiment revealed that these MVHMs had super adsorption performance and high selectivity for Pb2+ by comparison with other five metal ions: Cu2+, Cd2+, Ni2+, Cr3+ and Zn2+. Especially, the adsorption quantity of MVHMs for Pb2+ could approach 2468 mg/g and the maximum adsorption ratio of qe[Pb2+]/qe[Cu2+] can reach 10.909. These values were much larger than the data obtained with the adsorbents reported in the last decade. A variety of models are applied to evaluate the effect of ionic groups. It was confirmed that -COOH plays a key role in adsorption of HIs and s-MoS2 also has a certain contribution. Conversely, ion exchange plays only a minor role during the period of adsorption process. Effective diffusion coefficient (Deff) of Pb(II) had the largest values among these metal ions. Hence, these hybrid membranes are promising adsorbents for the removal of Pb2+ from water containing various ions.
摘要:
铅(II)是重金属离子(HIs)的潜在致癌物。随着含铅产品包括铅合金产品的广泛应用,和新能源铅离子电池,铅污染已经成为一个棘手的问题。为了解决这样的困难,通过丙烯酸共聚合成了具有“弹簧”效应的新型超薄MoS2-乙烯基杂化膜(MVHM),研究了苯乙烯和二硫化钼(MoS2)及其对HIs的吸附作用。“弹簧”效应源于与MoS2连接的短聚丙烯酸(PAA)链向外扩散的趋势与MoS2(s-MoS2)的层间库仑力之间的相互作用,这扩大了MoS2层的间距,而不改变膜形成后的层数,将溶胀膜变为致密膜,并在厚度方向上将原始厚度从0.5cm减小到0.011mm。吸附实验表明,与其他五种金属离子Cu2+相比,这些MVHMs具有超强的吸附性能和对Pb2+的高选择性,Cd2+,Ni2+,Cr3+和Zn2+。尤其是,MVHM对Pb2+的吸附量可达2468mg/g,qe[Pb2+]/qe[Cu2+]的最大吸附比可达10.909。这些值比过去十年中报道的吸附剂获得的数据大得多。应用多种模子来评价离子基团的感化。证实了-COOH对HIs的吸附起关键作用,s-MoS2也有一定的贡献。相反,离子交换在吸附过程中只起次要作用。在这些金属离子中,Pb(II)的有效扩散系数(Deff)最大。因此,这些杂化膜是用于从含有各种离子的水中去除Pb2+的有前途的吸附剂。