有机酸改性对电石渣碳酸化及循环特性的影响研究  

Study on the effect of organic acid modification on carbonation and cycle performance of carbide slag

作　　者：宋浩 卢奕江 谌缘 胡强 陈汉平[1] 杨海平[1] SONG Hao;LU Yijiang;CHEN Yuan;HU Qiang;CHEN Hanping;YANG Haiping(State Key Laboratory of Coal Combustion,School of Energy and Power Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]华中科技大学能源与动力工程学院煤燃烧与低碳利用全国重点实验室,湖北武汉430074

出　　处：《燃料化学学报(中英文)》2025年第4期481-492,共12页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金杰出青年科学基金(52125601)资助。

摘　　要：本研究采用四种有机酸浸渍改性电石渣,利用热重分析仪对改性前后的电石渣进行CO_(2)循环吸附-脱附实验研究,并对其物理化学结构进行表征以探究改性机制。结果表明,改性后电石渣中的钙主要以有机酸钙及其水合物的形式存在,煅烧后依次转变为CaCO_(3)和CaO。煅烧过程伴随着CaO晶体的生长,晶粒尺寸在700和800℃两次跳跃性增大。有机酸改性全面降低了电石渣中CaO的晶粒尺寸并提高了比表面积,同时也削弱了碱性位点强度。乙酸改性电石渣分解速率高达18.2%min^(-1),使其具有最小的平均孔径、最丰富的介孔结构、疏松的表面形貌和相对较低的晶粒尺寸。有机酸改性在首次吸附时均能提高电石渣吸附能力,其中,乙酸改性效果最好,第1次循环的碳酸化转化率为73.64%,15次循环后仍能维持34.68%,甲酸改性效果最差。比表面积和碱性位点强度对CO_(2)吸附能力的影响最为显著,对电石渣进行改性时,应着重提高比表面积和碱性位点强度,此外也要兼顾降低晶粒尺寸,提高介孔和微孔的含量。In this paper,four organic acids were used to modified carbide slag via impregnate,and a thermogravimetric analyzer was employed to conduct CO_(2)cyclic adsorption/desorption experiments on the carbide slag before and after modification.The physicochemical structure of the modified carbide slag is also characterized to investigate the modification mechanism.The results showed that the Ca in modified carbide slag primarily exists as organic acid calcium and their hydrates,which sequentially transformed into CaCO_(3)and CaO upon calcination.The calcination process is accompanied by crystal growth of CaO,with the crystallite size showing jumped increases twice observed at 700 and 800℃.The organic acid modification comprehensively reduced the CaO crystallite size,increased the specific surface area of carbide slag,and also weakened the alkaline site strength.The decomposition rate of acetic acid modified carbide slag was as high as 18.2%min^(-1),which resulting in the smallest average pore size,the richest mesoporous structure,a loose surface morphology and the relatively low crystallite size.Organic acid modification improved the initial CO_(2)adsorption capacity of carbide slag,acetic acid modification has the best effect among which,with the carbonation conversion rate of 73.64%in the first cycle and still retained 34.68%after 15 cycles,while formic acid modification showed the worst effect.Specific surface area and alkaline site strength were found to have the greatest influence on the CO_(2)adsorption capacity.Therefore,modification of carbide slag should prioritize improving the specific surface area and alkaline site strength,alongside reducing the crystallite size,and increasing the mesopores and micropores content.

关 键 词：电石渣 有机酸改性 碳酸化 循环稳定性 结构 机理 

分 类 号：TK6[动力工程及工程热物理—生物能] X701[环境科学与工程—环境工程] TQ424[化学工程]