Agro-Environmental Protection Institute, Chinese Academy of Agricultural Sciences, No. 31, Fukang Road, Nankai District, Tianjin 300191, China.
Research Center of Supercritical Fluid Technology, Tohoku University, 6-6-11 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan.
Bioresour Technol. 2019 Dec;294:122198. doi: 10.1016/j.biortech.2019.122198. Epub 2019 Sep 25.
Black liquor-derived calcium-activated biochars (Ca-biochar) were synthesized by treating rice straw with Ca(OH) to create an adsorbent that was effective for removing phosphate from aqueous waste streams. The Ca(OH) acts to separate lignin from the biomass, create pores in the biochar solids and form active adsorption sites. The Ca-biochar adsorbent was efficient for the removal of phosphate from aqueous solutions (pH 1.0 to pH 13.0) with a highest phosphate adsorption capacity of 197 mg/g. Phosphate adsorption was correlated with pseudo-second-order kinetics and the Langmuir model with primary mechanisms being attributed to chemical precipitation and ligand exchange. Application of the Ca-biochar (0.2 g/L) to actual wastewater from a cattle farm (phosphorus content 3.78 mg/L) reduced the phosphorus content to 0.021 mg/L. This work utilizes waste black liquor to prepare functionalized biochar materials, providing a promising approach for black liquor reuse and phosphate removal and recovery from phosphorus-rich waste streams.
利用稻草与 Ca(OH)₂反应制备黑液衍生的钙激活生物炭（Ca-biochar），用作吸附剂以有效去除废水中的磷酸盐。Ca(OH)₂可以将木质素从生物质中分离出来，在生物炭固体中形成孔，并形成活性吸附位。Ca-biochar 吸附剂能有效去除 pH 值为 1.0 至 13.0 的水溶液中的磷酸盐，最大吸附容量为 197 mg/g。磷酸盐的吸附与拟二级动力学和 Langmuir 模型相关，主要机制归因于化学沉淀和配体交换。将 0.2 g/L 的 Ca-biochar 应用于来自奶牛场的实际废水（磷含量 3.78 mg/L），可将磷含量降低至 0.021 mg/L。这项工作利用废黑液制备功能化生物炭材料，为黑液再利用以及从富磷废水中去除和回收磷酸盐提供了一种很有前景的方法。
