脱硫石膏改性固体胺复合材料的制备及脱碳性能  

Desulfurized gypsum modification on solid amine adsorbents and CO_2 adsorption in flue gas

作　　者：许静文 昌晶[2] 远富启 田红景[1] 郭庆杰[1,3] 王凯 XU Jingwen;CHANG Jing;YUAN Fuqi;TIAN Hongjing;GUO Qingjie;WANG Kai(College of Chemical Engineering, Qingdao University of Science ＆ Technology, Qingdao 266042, Shandong, China;College of Resources and Environment, Qingdao Agricultural University, Qingdao 266109, Shandong, China;State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering, Ningxia University, Yinchuan 750021, Ningxia, China)

机构地区：[1]青岛科技大学化工学院,山东青岛266042 [2]青岛农业大学资源与环境学院,山东青岛266109 [3]宁夏大学省部共建煤炭高效利用与绿色化工国家重点实验室,宁夏银川750021

出　　处：《化工学报》2018年第5期2100-2109,共10页CIESC Journal

基　　金：国家自然科学基金项目(51608291;51106077);青岛市自主创新计划项目(16-5-1-30-jch);山东省自然科学基金项目(ZR2015PE026;ZR2017QB019);煤炭高效利用与绿色化工国家重点实验室开放课题(2017-K19)~~

摘　　要：将榴莲壳碳化制备生物炭(BC),与硅钙渣混合作复合载体,在其表面浸渍负载五乙烯六胺(PEHA),并加入含水分的脱硫石膏(FGDG),得到胺功能化的含水CO_2固体吸附剂,与不含脱硫石膏的吸附剂相比吸附活性明显改善。通过FT-IR、TGA、SEM及N2吸脱附等手段对吸附剂进行了表征,并在固定床反应器中考察了吸附剂脱硫石膏含量、吸附温度和CO_2浓度对吸附性能的影响。结果表明,脱硫石膏中水的存在改变了氨基与CO_2的相互作用机理。当脱硫石膏含量为30%、吸附温度为85℃时,CO_2最大吸附量为2.33 mmol/g。经12次循环再生后吸附量仅下降了4.2%,表现出良好的吸附稳定性。Clausius-Clapeyron方程计算的等量吸附热介于物理与化学吸附热之间,说明吸附过程中物理与化学作用同时进行。用多个动力学模型对实验数据进行拟合,pseudo-first-order与pseudo-second-order模型均不能准确拟合实验数据,而Avrami模型可较好地拟合整个吸附过程,进一步验证BC/SCS-PEHA-30%FGDG的CO_2吸附过程并非单纯的物理或化学吸附,而是两者同时发生。Biochar（BC） obtained from durian shell carbonization was mixed with silicium-calcium slag particles as adsorbent carrier material. The mixture of BC and silicium-calcium slag particles was impregnated with pentaethylenehexamine（PEHA） liquid and then mixed with wet flue gas desulfurized gypsum（FGDG） slags to prepare wet amine functionalized CO2 solid adsorbents, which significantly improved adsorption activity than FGDG-free adsorbents. The adsorbents were characterized by FT-IR, TGA, SEM and N2 adsorption-desorption. Effect of FGDG slag content, adsorption temperature and CO2 concentration in flue gas on adsorption performance were studied in a fixed bed reactor. The results showed that moisture presence in FGDG slags changed reaction mechanisms between amino groups and CO2. Adsorbent with 30% FGDG had a maximum adsorption capacity of 2.33 mmol/g at temperature of 85℃ and its adsorption capacity decreased slightly by only 4.2% after 12 cycles of regeneration and reuse, showing a favorable adsorption stability. The isosteric heat of CO2 adsorption calculated with Clausius-Clapeyron equation was found between heats of physical and chemical adsorption, suggesting simultaneous occurrence of physical and chemical interactions in adsorption process. Fitting experimental data with kinetic models showed that pseudo-first-order and pseudo-second-order models did not fit accurately but Avrami model fitted well, which further indicated that CO2 adsorption process on BC/SCS-PEHA-30%FGDG is not a simple physical or chemical adsorption process, but a combination of these two adsorption processes.

关 键 词：生物炭 五乙烯六胺 吸附 稳定性 动力学模型 

分 类 号：TQ028[化学工程]