Guangxi Key Laboratory for Polysaccharide Materials and their Modification of Guangxi Minzu Univerisity , Key Laboratory of New Technology for Chemical and Biological Transformation Process of Guangxi Higher Education Institutes, College of Chemistry and Chemical Engineering, Guangxi Minzu University, Nanning, Guangxi 530006, PR China.
Guangxi Key Laboratory for Polysaccharide Materials and their Modification of Guangxi Minzu Univerisity , Key Laboratory of New Technology for Chemical and Biological Transformation Process of Guangxi Higher Education Institutes, College of Chemistry and Chemical Engineering, Guangxi Minzu University, Nanning, Guangxi 530006, PR China.
J Colloid Interface Sci. 2022 Sep 15;622:562-576. doi: 10.1016/j.jcis.2022.04.069. Epub 2022 Apr 13.
In this study, slag-based geopolymer microspheres (SGS) were combined with dithiocarbamate (DTC) to synthesize the composite adsorbent of SGS and DTC in situ (SGS-DTC). Synthesis was carried out with optimal dosages of 10 mL of EDA, 1.0 g of SGS, and 20 mL of CS. The differences in material properties, performance, and mechanisms in the adsorption and immobilization of toxic Cd(II) in water between SGS and SGS-DTC were investigated. SGS-DTC showed better adsorption performance than SGS, irrespective of adsorbent dosage, pH, original content, and contact duration. Although after the Cd(II) adsorption, the immobilization performance at a different pH was better in the SGS-DTC than in the SGS, the immobilization performance was unaffected by changes in the other factors. For static adsorption, the adsorption rate of SGS-DTC (1.5 h) was faster than that of SGS (6 h); the Cd(II) adsorption capacity of SGS-DTC (211.2 mg/g) was almost twice that of SGS (116.7 mg/g), and correspondingly, the removal rate of SGS-DTC (99.75%) was nearly twice that of SGS (53.2%). For dynamic adsorption, the adsorption capacity of SGS-DTC was 389.78 mg/g, which is considerably higher than that of SGS (293.38 mg/g) in the Cd(II) solution prepared with deionized water. Furthermore, the adsorption capacity of the SGS-DTC was 299.26 mg/g, which is significantly higher than that of SGS (150.03 mg/g) in the Cd(II) solution prepared by the river water from Yongjiang, Nanning, Guangxi, China. One reason is that DTC was able to activate Si-O-Si without adsorption performance within SGS, thereby improving its adsorption and purification properties significantly. The other reason is that, after anchoring DTC on SGS, the specific surface area varied from 34.05-146.47 m/g, the morphology was smooth-leaf-like, the pore volume was 0.13-0.20 cm/g, and the pore size in SGS, was 14.75-5.60 nm. The high potential of SGS-DTC in removing and immobilizing heavy metal materials in wastewater is demonstrated in the results.
在这项研究中，将矿渣基地质聚合物微球（SGS）与二硫代氨基甲酸盐（DTC）结合，原位合成了 SGS 和 DTC 的复合吸附剂（SGS-DTC）。合成过程中，最佳 EDA 用量为 10mL，SGS 用量为 1.0g，CS 用量为 20mL。研究了 SGS 和 SGS-DTC 在水中吸附和固定有毒 Cd(II)的材料性质、性能和机理的差异。无论吸附剂用量、pH 值、原始含量和接触时间如何，SGS-DTC 的吸附性能均优于 SGS。虽然在不同 pH 值下，Cd(II)吸附后 SGS-DTC 的固定性能优于 SGS，但其他因素的变化并不影响固定性能。对于静态吸附，SGS-DTC（1.5h）的吸附速率快于 SGS（6h）；SGS-DTC 的 Cd(II)吸附容量（211.2mg/g）几乎是 SGS 的两倍（116.7mg/g），相应地，SGS-DTC 的去除率（99.75%）也几乎是 SGS 的两倍（53.2%）。对于动态吸附，在去离子水中制备的 Cd(II)溶液中，SGS-DTC 的吸附容量为 389.78mg/g，明显高于 SGS（293.38mg/g）。此外，在广西南宁邕江河水制备的 Cd(II)溶液中，SGS-DTC 的吸附容量为 299.26mg/g，明显高于 SGS（150.03mg/g）。一个原因是 DTC 能够在没有吸附性能的情况下激活 SGS 中的 Si-O-Si，从而显著提高其吸附和净化性能。另一个原因是，DTC 锚定在 SGS 上后，比表面积从 34.05-146.47m2/g，形态为光滑叶片状，孔体积为 0.13-0.20cm2/g，孔径在 SGS 中为 14.75-5.60nm。结果表明，SGS-DTC 在去除和固定废水中重金属材料方面具有很高的潜力。
