School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, 221116, People's Republic of China.
Department of Biological and Environmental Engineering, Cornell University, 226 Riley-Robb Hall, Ithaca, NY, 14853, USA.
Environ Sci Pollut Res Int. 2021 Aug;28(32):44277-44287. doi: 10.1007/s11356-021-13858-x. Epub 2021 Apr 13.
Composite mineral-biochars of a homogeneous biomass (cellulose) and heterogeneous biomass (oak leaves) were fabricated with either 5 wt% or 10 wt% minerals (montmorillonite (MMT), kaolinite, and sand) and then pyrolyzed at 600 °C for 60 min. Characterizations including proximate analysis, ultimate analysis, surface area and porosity, morphology, and surface chemistry confirmed that minerals were present on the surface of biochar, and MMT/kaolinite-biochar composites showed a strengthening in the chars' aromatic structures, as well as increases in oxygen-containing surface functional groups. Methylene blue adsorption isotherms indicated that the MMT/kaolinite-biochars had higher adsorption capacities than pure biomass or biomass-sand biochars (110 mg/g and 24 mg/g for MMT-cellulose char and cellulose char, respectively). A multilinear model relating adsorption capacity and adsorbent properties was developed to measure the relative contribution of biochar properties to adsorption behavior. The model indicates that pore volume and hydrogen bonding were the dominant properties in controlling the adsorption of methylene blue onto the biochars. Findings from this work indicate that composite biochars prepared from biomass and inexpensive clay minerals are a promising adsorbent for remediating organic contaminants from water.
将同质生物质（纤维素）和异质生物质（橡树叶）与 5wt%或 10wt%的矿物质（蒙脱石（MMT）、高岭土和砂）混合制成复合矿物-生物炭，然后在 600°C 下热解 60 分钟。通过进行元素分析、表面面积和孔隙率分析、形貌分析和表面化学分析，证实了矿物质存在于生物炭表面，并且 MMT/高岭土-生物炭复合材料表现出增强的炭质芳香结构，以及增加的含氧表面官能团。亚甲基蓝吸附等温线表明，MMT/高岭土-生物炭比纯生物质或生物质-砂生物炭具有更高的吸附容量（MMT-纤维素炭和纤维素炭的吸附容量分别为 110mg/g 和 24mg/g）。建立了一个多元线性模型来关联吸附容量和吸附剂特性，以衡量生物炭特性对吸附行为的相对贡献。该模型表明，孔体积和氢键是控制亚甲基蓝吸附到生物炭上的主要特性。这项工作的结果表明，由生物质和廉价粘土矿物制备的复合生物炭是一种很有前途的吸附剂，可以从水中去除有机污染物。
