Bifunctional Ni/CaO-HZSM-5 Catalysts as a Two-Step Strategy To Produce n-Hexanol from Alkali Lignin

Abstract

The production of high-value-added chemicals from the degradation of real lignin still has been an unresolved issue. In this study, a two-step strategy was proposed to obtain n-hexanol from alkali lignin, and high conversion of alkali lignin and selectivity of n-hexanol were achieved. The deoxygenation performance of the synthesized Ni-HZSM-5 catalyst, modified by Ca, was efficiently improved. At first, through the deoxygenation of alkali lignin via Ni/CaO-HZSM-5, the C−O bonds of the material were broken effectively and 44% degree of deoxygenation (DOD) was obtained. Second, n-hexanol was selectively produced over the Ni/HZSM-5 catalyst from the liquid product obtained by the first step. The efficiency of deoxygenation (DOD) was attained at 71%, and the heat value increased to 51.6 MJ/kg from 19.9 MJ/kg after the two-step strategy. This strategy showed a high catalytic effect to produce n-hexanol from alkali lignin using Ni/CaO-HZSM-5 and Ni/HZSM-5 catalysts and revealed a superior advantage in the hydrodeoxygenation of real lignin to form high additional value chemicals.

Selective Conversion of Lignin Catalyzed by Palladium Supported on N-Doped Carbon

“…Among all catalysts, alkaline catalysts have great potential in the selective conversion of lignin. When alkaline catalysts catalyze lignin depolymerization, they can not only improve the selectivity of a single product but also reduce the formation of coke. , …”

“…When alkaline catalysts catalyze lignin depolymerization, they can not only improve the selectivity of a single product but also reduce the formation of coke. 18,20 Noble metal catalysts have good catalytic properties for the hydrogenolysis of lignin. 4,21,22 Meng et al used RuW/HY 30 (3.5 wt % Ru and 20 wt % W) as a catalyst to depolymerize pine lignin, and the yield of benzene reached 18.8 wt %.…”

Efficient Hydrodeoxygenation of Lignin-Derived Phenols to C6+ Cycloalkanols/Cycloalkanes over Magnetic Carbon-Encapsulated Nickel Nanospheres

“…The detriments of carbon emission have prompted the demands of clean energy to replace primary energy, which have become increasingly urgent. Non-food biomass waste as one clean energy would be a low-cost solution for this issue. − Bio-oil as a product of the biomass conversion could be utilized as a liquid energy. , However, the high oxygen content and low heating values would restrict it to be an alternative of fuels. Generally, hydrodeoxygenation (HDO) could be an effective process for the upgradation of lignin. − A series of heterogeneous catalysts have been studied for the HDO process, which loaded noble or non-precious metals. , Noble-metal-based catalysts that relied on their excellent HDO activity have received attention, but widespread industrial applications are confined because of their insufficient resource and high cost.…”