Gondek Krzysztof, Baran Agnieszka, Boguta Patrycja, Bołdak Małgorzata
Department of Agricultural and Environmental Chemistry, University of Agriculture in Krakow, al. Mickiewicza 21, 31-120 Krakow, Poland.
Institute of Agrophysics, Polish Academy of Sciences, Doświadczalna 4 Str., 20-290 Lublin, Poland.
Materials (Basel). 2024 Dec 17;17(24):6174. doi: 10.3390/ma17246174.
Composite materials based on diatomite (DT) with the addition of biochar (BC), dolomite (DL), and bentonite (BN) were developed. The effect of chemical modification on the chemical structure of the resulting composites was investigated, and their influence on heavy metal immobilization and the ecotoxicity of post-flotation sediments was evaluated. It was demonstrated that the chemical modifications resulted in notable alterations to the chemical properties of the composites compared to pure DT and mixtures of DT with BC, DL, and BN. An increase in negative charge was observed in all variants. The addition of BC introduced valuable chemically and thermally resistant organic components into the composite. Among the chemical modifications, composites with the addition of perlite exhibited the lowest values of negative surface charge, which was attributed to the dissolution and transformation of silicon compounds and traces of kaolinite during their initial etching with sodium hydroxide. The materials exhibited varying efficiencies in metal immobilization, which is determined by both the type of DT additive and the type of chemical modification applied. The greatest efficacy in reducing the mobility of heavy metals was observed in the PFS with the addition of DT and BC without modification and with the addition of DT and BC after the modification of HSO and HO: Cd 8% and 6%; Cr 71% and 69%; Cu 12% and 14%; Ni 10% and Zn 15%; and 4% and 5%. In addition, for Zn and Pb, good efficacy in reducing the content of mobile forms of these elements was observed for DT and DL without appropriate modification: 4% and 20%. The highest reduction in ecotoxicity was observed in the PFS with the addition of DT and BC, followed by BN and DL, which demonstrated comparable efficacy to materials with DT and BN.
开发了基于硅藻土（DT）并添加生物炭（BC）、白云石（DL）和膨润土（BN）的复合材料。研究了化学改性对所得复合材料化学结构的影响，并评估了它们对重金属固定以及浮选后沉积物生态毒性的影响。结果表明，与纯DT以及DT与BC、DL和BN的混合物相比，化学改性导致复合材料的化学性质发生了显著变化。在所有变体中均观察到负电荷增加。BC的添加将有价值的化学和耐热有机成分引入到复合材料中。在化学改性中，添加珍珠岩的复合材料表现出最低的表面负电荷值，这归因于硅化合物和痕量高岭石在氢氧化钠初始蚀刻过程中的溶解和转化。这些材料在金属固定方面表现出不同的效率，这取决于DT添加剂的类型和所应用的化学改性类型。在添加未改性的DT和BC以及在HSO和HO改性后添加DT和BC的PFS中，观察到降低重金属迁移率的效果最佳：镉分别为8%和6%；铬分别为71%和69%；铜分别为12%和14%；镍分别为10%和锌为15%；以及4%和5%。此外，对于锌和铅，在未进行适当改性的DT和DL中观察到降低这些元素可移动形式含量的良好效果：分别为4%和20%。在添加DT和BC的PFS中观察到生态毒性降低最多，其次是BN和DL，它们表现出与含DT和BN的材料相当的效果。
