负载的Ni催化剂上植物油脂加氢脱氧制备第二代生物柴油

在半连续反应器中,以棕榈酸甲酯为植物油脂模型化合物,进行了加氢脱氧制取高品质生物柴油燃料的研究。采用浸渍法制备了HY、SiO₂、γ-Al₂O₃及SAPO-11四种载体负载的Ni催化剂,采用XRD、NH₃-TPD、H₂-TPR、BET、SEM等技术进行催化剂表征。结果表明,Ni/SAPO-11催化剂由于SAPO-11表面呈现的弱酸和中强酸性质,在保持较高的加氢脱氧反应性的同时,抑制了裂解反应的发生,具有较好的催化性能。进一步对SAPO-11上不同的Ni负载量、反应温度、反应压力等进行了研究,发现当Ni负载量为7%,反应温度为220℃,压力为2MPa时,催化剂具有较高的催化性能,棕榈酸甲酯的转化率达到了99.8%,C_9~16烷烃的总选择性为92.71%。

Catalytic hydrodeoxygenation of vegetable oil over Ni catalysts to produce second-generation biodiesel

A series of Ni catalysts supported on HY, SiO₂, γ-Al₂O₃ and SAPO-11 were prepared by incipient-wetness impregnation and characterized by XRD, NH₃-TPD, H₂-TPR, BET and SEM techniques. Their catalytic performance in hydrodeoxygenation (HDO) of vegetable oil to produce the second-generation biodiesel was evaluated in a semi-batch reactor by using methyl palmitate as a model compound. Owning to the weak and medium acidic properties of SAPO-11, the Ni/SAPO-11 catalyst exhibits high activity in the HDO of methyl palmitate and capability of inhibiting the feedstock and long-chain alkanes from being cracked. The effect of Ni loading, reaction temperature and pressure on the HDO behavior over Ni/SAPO-11 catalyst was considered. Under 220℃ and 2 MPa, Ni/SAPO-11 catalyst with a Ni loading of 7% performs best in HDO; the conversion of methyl palmitate and the selectivity towards C_9~16 alkanes reach 99.8% and 92.71%, respectively.