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

Zhaozhuo Yu,Song Yang,Hu Li,Weibo Wu

doi:10.1155/2020/4809127

Abstract

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.

Highlights

Diversiform sustainable clean energies have been developed to get rid of the dependence of nonrenewable fossil energy and relieve environmental deterioration caused by combustion of fossil fuel in past decades [1,2,3]
E results listed in Figure 2 show that KF supported on acidic montmorillonite K-10 (K-10) and alkaline hydroxyapatite microspheres (HAP) and nanomagnesium oxide (MgO) performed poor reactivity in this reaction system, which could be attributed to the ion exchange between the support with KF [60] or the competing reaction of fluoride ion and hydroxide released from the support [61], remarkably weakening the nucleophilic attack ability of KF
N2 adsorptiondesorption isotherms of KF/support in different loading rates are presented in Figure S3. e hysteresis loop appearing in the N2 adsorption-desorption isotherms of 5 wt.% and 15 wt.% KF/ZrO2 (Figure S3) is the phenomenon of decrease in pore diameter of 5 wt.% and 15 wt.% KF/ZrO2 catalysts, proving the inference why the catalytic activity of 15 wt.% KF/ZrO2 catalyst is declined

Summary

Introduction

Diversiform sustainable clean energies have been developed to get rid of the dependence of nonrenewable fossil energy and relieve environmental deterioration caused by combustion of fossil fuel in past decades [1,2,3]. With the reaction temperature exceeding the boiling point of FUR (167°C), FFA can be efficiently prepared from gas state FUR and hydrogen gas in atmospheric pressure, which indicates that the hydrogenation of FUR can react in both vapor state and liquid state. Besides gas-phase H-donor hydrogen gas and alcohol H-donor, increasing reports about the hydrogenation of FUR to FFA by another liquid H-donor hydrosilane have been presented in the past decade [50, 51]. In this reaction system, FFA is obtained from FUR in high selectivity under mild conditions (atmospheric pressure,

Results and Discussions

MPa H2 1 MPa H2 3 MPa H2

Conclusion

Materials and Experiments