In the present work the valorization of natural mordenite as a catalyst support was investigated. Natural mordenite of Greek origin was activated by acid treatment with an aqueous solution of HCl. This treatment led to a material with a high specific surface area (156 m2 g–1). Ni catalysts (10 wt % Ni) supported on activated mordenite were synthesized by incipient wetness impregnation (IWI), wet impregnation (WI), infiltration (INF), and deposition–precipitation (DP). They were evaluated for the biodiesel upgrading into renewable diesel via hydrotreatment. DP was proven to be the most effective preparation method. In fact, an almost total conversion of biodiesel and production of the highest amount of green diesel (14 wt % of the liquid product) was achieved over the catalyst prepared by DP. Its high efficiency was attributed to its enhanced specific surface area, better nickel dispersion (smaller size of crystallites), and the smaller amount of carbon deposits on its surface compared to the other catalysts of this series. When the DP method was adopted, nickel catalysts supported on activated mordenite were synthesized varying active phase loading in the range 10–30 wt %. The catalyst with the maximum nickel loading exhibited high specific surface area and the highest Ni surface area as well as a balanced population of weak and strong acid sites. These characteristics resulted in the highest efficiency for green diesel production (25 wt % of the liquid product) among the catalysts studied.
In the present work, natural mordenite originated from volcanic soils in Greek islands, activated using HCl solution and HCl solution followed by NaOH solution, was used as support for preparing two metallic nickel catalysts (30 wt.% Ni). The catalysts were thoroughly characterized (XRF, N2 adsorption–desorption, SEM, XRD, TEM, H2-TPR, NH3-TPD) and evaluated for biodiesel upgrading to green (renewable) diesel. Double activation of natural mordenite optimized its supporting characteristics, finally resulting in a supported nickel catalyst with (i) enhanced specific surface area (124 m2 g−1) and enhanced mean pore diameter (14 nm) facilitating mass transfer; (ii) easier nickel phase reduction; (iii) enhanced Ni0 dispersion and thus high active surface; (iv) balanced population of moderate and strong acid sites; (v) resistance to sintering; and (vi) low coke formation. Over the corresponding catalyst, the production of a liquid consisting of 94 wt.% renewable diesel was achieved, after 9 h of reaction at 350 °C and 40 bar H2 pressure, in a semi-batch reactor under solvent-free conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.