A Highly-Efficient KF-Modified Nanorod Support Zr−Ce Oxide Catalyst and its Application

3D Hollow Mg-Ca-Al Hydrotalcite-Like Compounds Doped with KF for Catalytic Transesterification

Herein, a kind of three-dimensional hollow Mg-Ca-Al hydrotalcite-like compounds (HTLCs) microsphere was prepared by self-assembly of hydrotalcite-like nanosheets. Mg-Ca-Al HTLCs microsphere (MS) has large specific surface area and large pore size, and the modification of KF·2H2O increases numerous alkaline active sites on the surface of the catalyst. The prepared catalyst has excellent catalytic effect for the production of biodiesel by transesterification. Under the optimal conditions of the catalyst addition amount which accounts for 2% of the weight of oil, the biodiesel yield of the best catalyst is as high as 92% within 30 minutes. This article also provides a paradigm of a rational structural design for regulating the morphology of HTLCs.

Highly Selective Reduction of Bio-Based Furfural to Furfuryl Alcohol Catalyzed by Supported KF with Polymethylhydrosiloxane (PMHS)

Hydrogenation of bio-based furfural (FUR) to furfuryl alcohol (FFA) is tremendously expanding the application of biomass in many industries such as resins, biofuels, and pharmaceuticals. However, mass manufacture of FFA from FUR is restrained by strict requirements of reaction conditions and expensive catalysts. In this work, an economical and benign catalytic system, containing an easily prepared and reusable catalyst 5 wt.% KF/ZrO2 and a low-cost hydrogen source polymethylhydrosiloxane (PMHS), was developed to be efficient for the hydrogenation of FUR to high-value FFA under mild conditions. The catalyst reactivity was found to be remarkably influenced by the support acid-base properties and KF loading doge. In the presence of 5 wt.% KF/ZrO2, a high FFA yield of 97% and FUR conversion of 99% could be obtained at 25°C in just 0.5 h, which was superior to those attained with other tested catalysts. The KF/ZrO2 catalyst could be recycled at least five times, with the FFA yield slightly decreasing from 97% to 71%. The spare decrease in FFA yield is possibly attributed to the catalyst pore blocking, as clarified by SEM, BET, XPS, and ICP-MS measurements of the fresh and reused catalysts.