PDF《生物质内源矿物对热解过程及生物炭稳定性的影响》

摘要: 选用花生壳和牛粪两种富碳生物质, 通过酸洗去矿和外加典型矿物的方法, 在热重分析仪中模拟热解过程, 探讨矿物对热 解行为的催化效应;

通过元素分析计算碳保留;

通过 K2Cr2O7 化学氧化以及拉曼光谱考察矿物对生物炭稳定性的影响.

结果表明: 内 源矿物对生物质热解中的分解温度有显著催化效应, 将碳骨架的主体分解温度从 250耀400 益降低到 200耀350 益;

花生壳中典型矿 物为 KCl, 牛粪中为 CaCl2;

矿物 CaCl2 对牛粪的分解催化效应比 KCl 对花生壳的催化效应更显著.生物质去矿后, 热解过程中碳保 留率并未发生显著变化, 但生物炭产物中碳稳定性提高.K2Cr2O7 氧化实验表明, 去矿花生壳和去矿牛粪制备的生物炭碳稳定性比 原始生物质制备的生物炭分别增加了 52.7%和30.6%;

通过拉曼光谱观察碳结构, 发现生物质去矿后制备的生物炭有序化增强 (ID/ IG 减小) , 说明矿物质使生物炭更易产生晶格缺陷, 对产物稳定性有负面作用. 因此, 生物质内源矿物的存在, 在热解时催化碳分解, 使得生物炭碳结构更无序化, 降低产物稳定性, 但对过程中碳保留率的影响不显著. 关键词: 生物质;

内源矿物;

热解;

碳保留;

催化效应;

碳稳定性 中图分类号: X71 文献标志码: A 文章编号: 1672-2043 (2017) 03-0591-07 doi:10.11654/jaes.2016-1160 Influence of inherent minerals on biomass pyrolysis and carbon stability in biochar GU Bo-wen, CAO Xin-de, ZHAO Ling* , ZHAO Ying-hao (School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China) Abstract: In this study, two common biomass residues, peanut shell and cow manure were selected to investigate these influences. The ex原periments were conducted including removing the inherent minerals through acid washing for biochar formation, adding typical minerals into demineralized biomass for biochar generation, and the resulted bichars were characterized by thermogravimetric analysis, elemental analysis, chemical oxidation, and Raman spectroscopy. Results show that the main inherent mineral in peanut shell and cow manure biomasses was KCl and CaCl2, respectively and they had a significant catalytic effect on the biomass pyrolysis by decreasing the decomposition temperature of carbon from 250~400 益to 200~350 益. CaCl2 showed a larger catalytic effect on the biomass pyrolysis than KCl. No obvious changes were observed on carbon retention (%)during biomass pyrolysis with mineral removal or addition, while in the absence of mineral the sta原bility of peanut shell and cow manure biochar was increased by 52.7% and 30.6%, respectively, indicated by oxidation of K2Cr2O7. Minerals promoted the lack of lattice in biochar (increased ID/IG ) , resulting in the reduced carbon stability. Overall, inherent minerals in biomass had catalytic effect on the decomposition of carbon skeleton during pyrolysis, and they made the carbon structure disordering, reducing the sta原bility of its carbon. Keywords: biomass;

inherent minerals;

pyrolysis;

carbon retention;

catalytic effect;

carbon stability 收稿日期: 圆园16原09原08 作者简介: 顾博文 (1992―) , 男, 江苏泰州人, 硕士, 主要研究生物炭材料.E-mail: [email protected] * 通信作者: 赵玲E-mail: [email protected] 基金项目: 国家自然科学基金项目 (21577087) Project supported: The National Natural Science Foundation of China (21577087) 圆园17,