Bian Pengyang, Liu Yixuan, Zheng Xiaoqin, Shen Weibo
College of Natural Resources and Environment, Northwest A&F University, Xianyang 712100, China.
Qinba Ecological Protection Center, Hanzhong 723000, China.
Polymers (Basel). 2022 Jul 16;14(14):2889. doi: 10.3390/polym14142889.
A new type of biochar, called GBC, was prepared from silkworm excrement, and then modified by chitosan combined with pyromellitic dianhydride. The removal of mono-metal and polymetals (Pb, Cd and Cu) from an aqueous solution by GBC was investigated in this research. Compared to unmodified biochar, the removal rate of Pb and Cd by GBC was about 12% higher, while that of Cu was about 94.6% higher. It also shows the types of functional groups in biochar have a great impact on their adsorption. The removal of Pb is mainly involved in the N-C=O functional group, the removal of Cd is mainly involved in N-containing functional group and C=C bond, and that of Cu is mainly involved in N-containing functional group, carboxyl group, hydroxyl group, and a carbonyl group. Five adsorption-desorption cycles of GBC were carried out, and it was found that the adsorption capacities of GBC for Pb, Cd and Cu decreased by 7.28%, 10.78% and 6.07%, respectively, indicating that GBC had a good renewable performance. The adsorption capacity of GBC for Cu in different water samples is between 89.62 and 93.47 mg·g, indicating that GBC has great application potential for the removal of Cu in wastewater.
一种名为GBC的新型生物炭由蚕粪制备而成，然后用壳聚糖与均苯四甲酸二酐进行改性。本研究考察了GBC对水溶液中单金属和多金属（铅、镉和铜）的去除情况。与未改性的生物炭相比，GBC对铅和镉的去除率高出约12%，而对铜的去除率高出约94.6%。这也表明生物炭中官能团的类型对其吸附有很大影响。铅的去除主要涉及N-C=O官能团，镉的去除主要涉及含氮官能团和C=C键，而铜的去除主要涉及含氮官能团、羧基、羟基和羰基。对GBC进行了五次吸附-解吸循环，发现GBC对铅、镉和铜的吸附容量分别下降了7.28%、10.78%和6.07%，表明GBC具有良好的可再生性能。GBC对不同水样中铜的吸附容量在89.62至93.47 mg·g之间，表明GBC在去除废水中的铜方面具有很大的应用潜力。
