| 高比表面积α-AlF3的制备和表征 | |
| Preparation and Characterization of High Surface Area α-AlF3 | |
| 摘要: 采用炭硬模板法制备了高比表面积的α-AlF3(HS-α-AlF3)。首先，将一定浓度的蔗糖溶液浸渍到γ-Al2O3中，然后经过热处理，使得蔗糖分解为炭。其次，将含炭的γ-Al2O3固体用HF气体进行氟化。最后，再利用燃烧法除去炭硬模板。采用XRD、低温氮吸附－脱附、NH3-TPD、SEM-EDX等技术对样品进行了表征。结果表明，当炭化温度为450 ℃时，HF-N2混合气体积比为1∶4，除碳温度为425 ℃时，制得的α-AlF3比表面积最大，为66 m2·g-1。此外，HS-α-AlF3催化剂对CCl2F2歧化反应的催化活性也明显高于常规方法制备的低比表面积的α-AlF3，这是因为高比表面积的α-AlF3催化剂具有较大的酸量。 | |
| 关键词: α-AlF3 高比表面积 炭硬模板 CCl2F2歧化反应 | |
| 基金项目: | |
| Abstract: High surface area α-AlF3(HS-α-AlF3) has been prepared by a carbon hard template method. The synthesis procedure consisted of three steps: (1) the impregnation of a sucrose (C12H22O11) aqueous solution with γ-Al2O3 and subsequent thermal treatment; (2) the thermal treatment of the obtained solid with HF; (3) the removal of the carbon template in C@α-AlF3 upon high temperature combustion. The optimal conditions for the highest surface area of the synthesized α-AlF3(66 m2·g-1) are obtained based on the results from XRD, low temperature adsorption-desorption, ammonia temperature programmed desorption (NH3-TPD), SEM, EDX and the FTIR spectra of pyridine adsorption. The temperatures for fluorination, carbon calcinations and carbon removal are 400, 450 and 425 ℃, respectively, and the HF/N2 volume ratio is 1∶4. In addition, the HS-α-AlF3 catalyst is more active for the dismutation of CCl2F2 than the catalyst prepared by a direct fluorination of the γ-Al2O3 due to its higher amount of acid sites. | |
| Keywords: α-AlF3 surface area carbon hard template dismutation of CCl2F2 | |
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| 于洪波,王月娟,彭小波,朱 琳,罗孟飞.高比表面积α-AlF3的制备和表征[J].无机化学学报,2012,28(5):905-909. | |
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