Zhongguo youzhi (Jan 2023)

TiO2 催化剂改性方法对光热催化麻疯树籽油制备 生物燃油的影响

  • 杨依婕1,2, 刘莹1, 张伟1, 刘娜1, 桂超1, 蔡正达3,孙鲁闽2，陈玉保1 YANG Yijie1,2, LIU Ying1, ZHANG Wei1, LIU Na1, GUI Chao1, CAI Zhengda3, SUN Lumin2, CHEN Yubao1

DOI
https://doi.org/10.19902/j.cnki.zgyz.1003-7969.210695
Journal volume & issue
Vol. 48, no. 1
pp. 53 – 59，65

Abstract

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为改善TiO2在光热催化过程中催化效率不高及回收困难等问题，分别使用固体分散法和溶胶凝胶法将TiO2与HZSM-5分子筛结合，并负载活性金属Pt制备Pt/TiO2-HZSM-5催化剂，对两种催化剂进行X射线衍射（XRD）、N2吸附-脱附、高分辨率透射电镜（HRTEM）、紫外-可见光（UV-Vis）、X射线荧光（XRF）及吡啶-红外（Py-IR）表征，并用于光热催化麻疯树籽油加氢制备生物燃油中，考察两种改性催化剂的催化效果。结果表明：两种制备方法均可使TiO2成功分散在HZSM-5分子筛表面，TiO2的比表面积增加，HZSM-5分子筛孔容和孔径改变；改性后的催化剂衍射峰出现明显红移，对可见光的吸收能力提高，酸性位点增加；相比溶胶凝胶法，固体分散法制备的Pt/TiO2-HZSM-5活性金属Pt分散度较好且无团聚现象，粒径更小，催化性能更优；在反应温度100 ℃、氢压0.4 MPa、反应时间12 h条件下，使用固体分散法制备的Pt/TiO2-HZSM-5光热催化麻疯树籽油制备生物燃油的原料转化率达93.20%、C8~C17烷烃选择性达54.92%，该催化剂的重复利用实验结果表明，催化剂再生后C8~C17烷烃选择性随着再生次数的增加而下降，可再生能力有待加强。 To improve the problems of low catalytic efficiency and difficult recovery of TiO2 in the photothermal catalysis process, the Pt/TiO2-HZSM-5 catalysts were prepared by combining TiO2 with HZSM-5 molecular sieve using solid dispersion method and sol-gel method, respectively, and loaded with active metal Pt.The two catalysts were characterized by X-ray diffraction (XRD), N2 adsorption-desorption, high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible light(UV-Vis), X-ray fluorescence (XRF) and pyridine-infrared (Py-IR), and used in the photothermal catalytic hydrogenation of Jatropha oil for the preparation of bio-fuel to investigate the catalytic effects of the two modified catalysts.The results showed that TiO2 was successfully dispersed on the surface of the HZSM-5 molecular sieve，the specific surface area of TiO2 increased, and the pore volume and pore size of the HZSM-5 molecular sieve changed.The modified catalyst showed a significant red shift in the diffraction peak with improved absorption of visible light, and the acidic sites increased.Compared with sol-gel method,Pt/TiO2-HZSM-5 prepared by solid dispersion method had better Pt dispersion and no agglomeration phenomenon, smaller particle size and better catalytic performance. With this catalyst, the material conversion and C8-C17 alkanes selectivity reaching 93.20%and 54.92%respectively in the photothermal catalytic hydrogenation of Jatropha oil for the preparation of bio-fuel under the conditions of reaction temperature 100 ℃,H2 pressure 0.4 MPa and reaction time 12 h. The results of the reuse experiments of this catalyst showed that the C8-C17 alkanes selectivity decreased with the increase of regeneration times, and the regeneration capacity should be strengthened.

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