Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, 650500 Kunming, China; Faculty of Civil Engineering and Mechanics, Kunming University of Science and Technology, Kunming, China; College of Chemistry and Environmental Science, Qujing Normal University, 655011 Qujing, China.
Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, 650500 Kunming, China.
J Colloid Interface Sci. 2021 Jul;593:434-446. doi: 10.1016/j.jcis.2021.02.118. Epub 2021 Mar 9.
With the increased awareness of reusing solid wastes for higher sustainability and the concern of water pollution associated with phosphorus over-emission, there are strong interests in developing solid waste based adsorbents for purifying phosphorus-containing wastewater. As a rich calcium resource, paper mill sludge (i.e., a major solid waste from pulping industry) can be used as phosphorus removal adsorbent after calcination. Thus, in this work, a simple and clean thermally treating route has been proposed for preparing calcium-containing biochar from paper mill sludge. The effect of the physicochemical properties of paper mill sludge and its carbonization condition on phosphorus adsorption has been analyzed. Moreover, the influence of some key adsorption parameters, e.g., biochar dosage, initial pH of solution, co-existing anions, initial phosphorus concentration and contact time has also been investigated. The results showed that the phosphorus adsorption data could be fitted well with pseudo-second-order kinetic and Langmuir isothermal models. The calculated maximum adsorption capacity of the as-prepared optimal calcium-containing biochar could reach to 68.49 mg·g at 25 °C. Combined with the characterization results, it can be reasonably inferred that the adsorption process was chemisorption-dominated. Lastly, the application of this spent adsorbent in agriculture field has also been discussed. In brief, this work provided a feasible strategy for converting paper mill solid waste to an environmental functional material (i.e., calcium-rich biochar) for remediation of eutrophic water.
随着人们对提高可持续性和减少磷过度排放相关水污染的认识不断增强，开发基于固体废物的吸附剂来净化含磷废水具有很大的兴趣。作为一种丰富的钙资源，造纸厂污泥（即制浆工业的主要固体废物）经过煅烧后可作为除磷吸附剂使用。因此，本工作提出了一种从造纸厂污泥中制备含钙生物炭的简单清洁热处理方法。分析了造纸厂污泥的物理化学性质及其碳化条件对磷吸附的影响。此外，还研究了一些关键吸附参数的影响，如生物炭用量、溶液初始 pH 值、共存阴离子、初始磷浓度和接触时间。结果表明，磷吸附数据可以很好地拟合准二级动力学和 Langmuir 等温模型。在 25°C 下，所制备的最佳含钙生物炭的最大吸附容量可达 68.49 mg·g。结合表征结果，可以合理推断吸附过程主要是化学吸附。最后，还讨论了这种废吸附剂在农业领域的应用。总之，本工作为将造纸厂固体废物转化为环境功能材料（即富钙生物炭）以修复富营养化水提供了一种可行的策略。
