Khedr Rania Fekry
Chemistry Department Al Leith, University College, Umm Al-Qura University, Mecca 24382, Saudi Arabia.
Department of Siting and Environment, Nuclear and Radiological Safety Research Center (NRSRC), Egyptian Atomic Energy Authority (EAEA), Cairo 11762, Egypt.
Polymers (Basel). 2022 Aug 1;14(15):3136. doi: 10.3390/polym14153136.
In the aquatic environment, heavy metals such as lead ions Pb (II) are of particular importance. These are due to Pb (II) being toxic at concentrations over 0.01 mg/L, when taken continuously over an extended length of time. Organs including the heart, gut, and kidneys are seriously harmed by Pb (II) intoxication. The neurological, reproductive, and bone systems are also affected. The removal of Pb (II) from aquatic environments is, therefore, crucial. Low density Polyethylene (LDPE) is grafted by radiation with Acrylonitrile and acrylic acid (PE-g-AN/AAc) for the adsorption of Pb (II). Factors that control the grafting process for optimum conditions, such as the effect of solvents, the air atmosphere, inhibitors, comonomer concentration, and composition and irradiation dose, are studied to obtain a high grafting yield without homopolymer formation and a higher water uptake. The results showed that the addition of 2.5% by wt% ferric chloride salt effectively inhibits homoploymerization of a mixture of 30% methanol and 70% HO used as a solvent in nitrogen. The highest graft yield obtained was 320% at a 25 kGy radiation dose with an 80/20 monomer composition and 60% comonomer concentration. The resulting composite films were characterized by XRD to analyze the dispersion properties of the material, SEM for the surface morphology, FTIR analysis for the functional groups, TGA, DSC for the thermal stability and elongation, and tensile strength for the mechanical properties. The uptake of Pb (II) from lead nitrate aqueous solution by (PE-g-AN/AAc) was observed under different conditions of the degree of grafting, contact time, metal ion concentration, and pH. The results obtained suggest LDPE-g-p (AN/AAc) as a superabsorbent for the Pb (II) ion's removal from an aqueous solution.
在水生环境中，诸如铅离子Pb(II)之类的重金属尤为重要。这是因为当长时间持续摄入时，Pb(II)在浓度超过0.01 mg/L时具有毒性。包括心脏、肠道和肾脏在内的器官会受到Pb(II)中毒的严重损害。神经、生殖和骨骼系统也会受到影响。因此，从水生环境中去除Pb(II)至关重要。通过辐射将低密度聚乙烯(LDPE)与丙烯腈和丙烯酸接枝(PE-g-AN/AAc)以吸附Pb(II)。研究了控制接枝过程以达到最佳条件的因素，如溶剂的影响、空气气氛、抑制剂、共聚单体浓度、组成和辐照剂量，以获得高接枝产率且无均聚物形成以及更高的吸水率。结果表明，添加2.5 wt%的氯化铁盐可有效抑制在氮气中用作溶剂的30%甲醇和70%水的混合物的均聚。在25 kGy辐射剂量、80/20单体组成和60%共聚单体浓度下获得的最高接枝产率为320%。通过XRD对所得复合膜进行表征以分析材料的分散性能，通过SEM分析表面形态，通过FTIR分析官能团，通过TGA、DSC分析热稳定性和伸长率，通过拉伸强度分析机械性能。在不同的接枝度、接触时间、金属离子浓度和pH条件下，观察了(PE-g-AN/AAc)对硝酸铅水溶液中Pb(II)的吸附。所得结果表明LDPE-g-p(AN/AAc)作为一种超吸收剂可从水溶液中去除Pb(II)离子。
