Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India.
Water Res. 2013 Jun 15;47(10):3497-506. doi: 10.1016/j.watres.2013.03.059. Epub 2013 Apr 9.
Chitosan is naturally occurring bio-polymer having strong affinity towards transition metal ions. Chitosan complexed with transition metal ions takes up inorganic arsenic anions from aqueous medium. In present work, As(V) sorption in the chitosan complexed with different metal ions like Cu(II), Fe(III), La(III), Mo(VI) and Zr(IV) were studied. Sorptions of As(V) in CuS embedded chitosan, (3-aminopropyl) triethoxysilane (APTS) embedded chitosan, epichlorohydrin (ECH) crosslinked chitosan and pristine chitosan were also studied. (74)As radiotracer was prepared specifically for As(V) sorption studies by irradiation of natural germanium target with 18 MeV proton beam. The sorption studies indicated that Fe(III) and La(III) complexed with chitosan sorbed 95 ± 2% As(V) from aqueous samples in the pH range of 3-9. However, Fe(III)-chitosan showed better sorption efficiency (91 ± 2%) for As(V) from seawater than La(III)-chitosan (80 ± 2%). Therefore, Fe(III)-chitosan was selected to prepare the self-supported membrane and poly(propylene) fibrous matrix supported sorbent. The experimental As(V) sorption capacities of the fibrous and self-supported Fe(III)-chitosan sorbents were found to be 51 and 109 mg g(-1), respectively. These materials were characterized by XRD, SEM and EDXRF, and used for preconcentration of As(V) in aqueous media like tap water, ground water and seawater. To quantify the As(V) preconcentrated in Fe(III)-chitosan, the samples were subjected to instrumental neutron activation analysis (INAA) using reactor neutrons. As(V) separations were carried out using a two compartments permeation cell for the self-supported membrane and flow cell using the fibrous sorbent. The total preconcentration of arsenic content was also explored by converting As(III) to As(V).
壳聚糖是一种天然存在的生物聚合物，对过渡金属离子具有很强的亲和力。壳聚糖与过渡金属离子形成复合物后，可从水溶液中摄取无机砷阴离子。在本工作中，研究了壳聚糖与不同金属离子（如 Cu(II)、Fe(III)、La(III)、Mo(VI)和 Zr(IV)）形成的复合物对 As(V)的吸附作用。还研究了 CuS 嵌入壳聚糖、(3-氨丙基)三乙氧基硅烷 (APTS) 嵌入壳聚糖、表氯醇 (ECH) 交联壳聚糖和原始壳聚糖对 As(V)的吸附作用。通过用 18 MeV 质子束辐照天然锗靶，专门制备了放射性核素 (74)As 用于 As(V)的吸附研究。吸附研究表明，壳聚糖与 Fe(III)和 La(III)形成的复合物在 pH 值为 3-9 的范围内从水溶液中吸附了 95±2%的 As(V)。然而，Fe(III)-壳聚糖对海水样品中 As(V)的吸附效率（91±2%）优于 La(III)-壳聚糖（80±2%）。因此，选择 Fe(III)-壳聚糖制备自支撑膜和聚（丙烯）纤维基质负载吸附剂。纤维状和自支撑 Fe(III)-壳聚糖吸附剂的实验 As(V)吸附容量分别为 51 和 109mg g(-1)。这些材料通过 XRD、SEM 和 EDXRF 进行了表征，并用于自来水中、地下水和海水中的 As(V)的预浓缩。为了定量测定 Fe(III)-壳聚糖中预浓缩的 As(V)，使用反应堆中子对样品进行了仪器中子活化分析 (INAA)。使用自支撑膜的两室渗透池和纤维状吸附剂的流动池进行了 As(V)的分离。通过将 As(III)转化为 As(V)，还探索了砷含量的总预浓缩。
