Ayaz Iram, Rizwan Muhammad, Ullman Jeffery Layton, Haroon Hajira, Qayyum Abdul, Ahmed Naveed, Elesawy Basem H, Askary Ahmad El, Gharib Amal F, Ismail Khadiga Ahmed
US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro 76062, Pakistan.
Department of Civil and Environmental Engineering, University of Utah, 201 Presidents Circle, Room 201, Salt Lake City, UT 84112, USA.
Polymers (Basel). 2022 Feb 12;14(4):715. doi: 10.3390/polym14040715.
wood is made up of lignocellulosic material; this lignocellulosic material contains two types of biopolymers, i.e., carbohydrate and aromatic polymers. In this study, this lignocellulosic material was used to prepare biochar. Three biochar, i.e., laboratory-based (B1), barrel-based (B2), and brick kiln-biochar (B3), were used for fluoride and arsenic removal from aqueous solution. Barrel-based biochar was prepared by using the two-barrel method's alteration. The highest fluoride removal (99%) was attained at pH 2 in the presence of B1, while in the presence of B2 and B3, maximum fluoride removal was 90% and 45.7%, respectively. At pH 10, the maximum arsenic removal in the presence of B1, B2, and B3 was 96%, 94%, and 93%, respectively. The surface characteristics obtained by Fourier-transform infrared spectroscopy (FTIR) showed the presence of carbonyl group (C-O), and alkene (C=C) functional groups on all the three studied biochars. Isotherm studies showed that the adsorption was monolayered (all the adsorbed molecules were in contact with the surface layer of the adsorbent) as the Langmuir isotherm model best fits the obtained data. Adsorption kinetics was also performed. The R value supports the pseudo-second-order kinetics, which means that chemisorption was involved in adsorbing fluoride and arsenic. It is concluded that B1 gives maximum removal for both fluoride (99%) and arsenic (96%). The study shows that lignocellulose-based biochar can be used for arsenic and fluoride removal from water.
木材由木质纤维素材料组成；这种木质纤维素材料包含两种生物聚合物，即碳水化合物和芳香族聚合物。在本研究中，这种木质纤维素材料被用于制备生物炭。三种生物炭，即实验室制备的（B1）、桶式制备的（B2）和砖窑生物炭（B3），被用于从水溶液中去除氟化物和砷。桶式生物炭是通过改进双桶法制备的。在B1存在的情况下，在pH值为2时实现了最高的氟化物去除率（99%），而在B2和B3存在的情况下，最大氟化物去除率分别为90%和45.7%。在pH值为10时，在B1、B2和B3存在的情况下，最大砷去除率分别为96%、94%和93%。通过傅里叶变换红外光谱（FTIR）获得的表面特征表明，在所有三种研究的生物炭上都存在羰基（C-O）和烯烃（C=C）官能团。等温线研究表明，吸附是单层的（所有吸附的分子都与吸附剂的表面层接触），因为朗缪尔等温线模型最适合所获得的数据。还进行了吸附动力学研究。R值支持准二级动力学，这意味着化学吸附参与了氟化物和砷的吸附。得出的结论是，B1对氟化物（99%）和砷（96%）的去除率最高。该研究表明，基于木质纤维素的生物炭可用于去除水中的砷和氟化物。
