School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
Bioresour Technol. 2018 Jul;259:191-197. doi: 10.1016/j.biortech.2018.03.046. Epub 2018 Mar 14.
Catalytic upgrading of pyrolysis vapor from rape straw was performed in a vacuum pyrolysis system over La/HZSM-5 with hierarchical structure. When 3M NaCO was used for alkali treatment, the desilication process of HZSM-5 zeolite was highly controllable and the hierarchical porous HZSM-5(Hi-ZSM-5) zeolite was formed. After that, Hi-ZSM-5 was modified by impregnation with lanthanum ion, the acid sites of Lewis increased and the concentrations ratio of Brönsted acid and Lewis acid of the catalyst was improved. The highest hydrocarbons selectivity (49.86%), the lowest carbonyl compounds content (11.06%), and reasonable catalytic stability were obtained by the La/Hi-ZSM-5 catalyst. In addition, La/Hi-ZSM-5 further reduced the coke content of the catalyst to 11.05%, while increasing the selectivity of high value aromatic hydrocarbons. Obviously, La/Hi-ZSM-5 zeolite had high catalytic activity, and exhibited good potential and a beneficial nature for efficient preparation of high-valued bio-oil from rape straw.
在真空热解系统中，通过浸渍法在具有分级结构的 La/HZSM-5 催化剂上对油菜秸秆热解蒸汽进行催化升级。当使用 3M NaCO 进行碱处理时，HZSM-5 沸石的脱硅过程具有高度可控性，形成了分级多孔 HZSM-5（Hi-ZSM-5）沸石。之后，通过浸渍法用镧离子对 Hi-ZSM-5 进行改性，增加了路易斯酸位，提高了催化剂的 Brönsted 酸和路易斯酸浓度比。通过 La/Hi-ZSM-5 催化剂获得了最高的烃选择性（49.86%）、最低的羰基化合物含量（11.06%）和合理的催化稳定性。此外，La/Hi-ZSM-5 进一步将催化剂的焦炭含量降低至 11.05%，同时提高了高价值芳烃的选择性。显然，La/Hi-ZSM-5 沸石具有较高的催化活性，对于从油菜秸秆高效制备高附加值生物油具有良好的潜力和有益性质。
