Li Zhonglin, Wang Ding, Shen Jialong, Chen Junxue, Wu Chengzhi, Qu Zizheng, Luo Kun, Meng Zhengbing, Li Yibing
Department of Materials Science and Engineering, Guilin University of Technology, Guilin 541000, China.
Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources, Guilin University of Technology, Guilin 541000, China.
Materials (Basel). 2021 Sep 22;14(19):5465. doi: 10.3390/ma14195465.
To mitigate the global greenhouse effect and the waste of carbon dioxide, a chemical raw material, high-purity γ-phase mesoporous alumina (MA) with excellent CO adsorption performance was synthesized by the direct aging method and ammonium salt substitution method. With this process, not only can energy consumption and time be shortened to a large extent but the final waste can also be recycled to the mother liquor by adding calcium hydroxide. Reaction conditions, i.e., pH value, calcination temperature, and desodium agent, were investigated in detail with the aid of X-ray fluorescence spectrum (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and Barret-Joyner-Hallender (BJH) methods, nonlocal density functional theory (NLDFT), transmission electron microscopy (TEM), temperature-programmed desorption of CO (CO-TPD), and presented CO adsorption measurement. The results of this study are summarized as follows: the impurity content of the MA synthesized under optimal conditions is less than 0.01%, and its total removal rate of impurities is 99.299%. It was found that the MA adsorbent has a large specific surface area of 377.8 m/g, pore volume of 0.55 cm/g, and its average pore diameter is 3.1 nm. Under the condition of a gas flow rate of 20 cm/min, its CO adsorption capacity is 1.58 mmol/g, and after 8 times of cyclic adsorption, the amount of CO adsorption remained basically unchanged, both of which indicate that the material has excellent adsorption properties and can be widely used for the adsorption of carbon dioxide.
为了减轻全球温室效应以及二氧化碳这种化学原料的浪费，采用直接老化法和铵盐替代法合成了具有优异CO吸附性能的高纯度γ相介孔氧化铝（MA）。通过该工艺，不仅能在很大程度上缩短能耗和时间，而且通过添加氢氧化钙，最终废料还能回收到母液中。借助X射线荧光光谱（XRF）、X射线衍射（XRD）、扫描电子显微镜（SEM）、布鲁诺尔-埃米特-泰勒（BET）和巴雷特-乔伊纳-哈伦德（BJH）方法、非局部密度泛函理论（NLDFT）、透射电子显微镜（TEM）、程序升温脱附CO（CO-TPD）以及进行CO吸附测量，详细研究了反应条件，即pH值、煅烧温度和脱钠剂。本研究结果总结如下：在最佳条件下合成的MA杂质含量小于0.01%，其杂质总去除率为99.299%。发现MA吸附剂具有377.8 m²/g的大比表面积、0.55 cm³/g的孔体积，其平均孔径为3.1 nm。在气体流速为20 cm/min的条件下，其CO吸附容量为1.58 mmol/g，经过8次循环吸附后，CO吸附量基本保持不变，这两者均表明该材料具有优异的吸附性能，可广泛用于二氧化碳的吸附。
