Synthesis of a Stable, Water-Tolerant, Short Mesoporous Organic Biguanide, Strong Solid Base and Its Application in Catalysis

摘要

Firstly, both a short mesopore thin plate molecular sieve of Zr- doped SBA-15 and a strong organic base of bi-guanides DIC- TMG were respectively prepared. Then, the organic bi-guanides DIC-TMG was grafted onto the short mesopore thin plate molecular sieve to prepare a highly efficient and stable water- tolerant short mesoporous organic bi-guanides strong solid base DIC-TMG/Zr-SBA-15 which was used to catalyze the transesterification of renewable bio-oils to biodiesel under mild reaction conditions. The prepared DIC-TMG/Zr-SBA-15 was elaborately investigated by XRD, BET, SEM, TEM, FT-IR and Elemental analysis. The obtained results showed that compared with TMG/Zr-SBA-15 and DIC-TMG/SBA-15, DIC-TMG/Zr-SBA-15 exhibited the best catalytic activity with 95% of biodiesel yield at reaction temperature 75°C and catalyst dosage 5 wt%. Especially, unlike some other usually solid metal-based cata- lysts, this alkaline organic bi-guanidines DIC-TMG supported on Zr-SBA-15 support catalyst has certain water-tolerant. With 1 wt % of water content existed in the reaction system, the biodiesel yield still reached 90%, and after five recycles of the catalyst, the biodiesel yield was still more than 80%.