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This work investigated the decomposition of anisole (methoxyl-based lignin model compound) in a fluidized bed reactor over no catalysts and a series of HZSM-5 zeolite catalysts with different Si/Al atomic ratios. Transmethylation reaction was identified as the initial step of the thermal decomposition of anisole, leading to the prominent production of phenolic compounds. Methyl phenols were identified as the main products, with the yield of o-cresol being higher than that of p-cresol at the temperatures below 600˚C. The transmethylation reaction over HZSM-5 zeolite catalyst was found to occur at temperatures 150˚C lower than those for non-catalytic reaction, with the yield of the phenolic compounds being promoted by 2.5 times. Production of the main phenolic compounds during the catalytic decomposition of anisole was enhanced to different extents depending on the Si/Al ratio. The highest selectivity of 79 wt. % was achieved over the zeolite catalyst with a Si/Al ratio of 80. The Brønsted acid sites of the catalyst played a significant role in both the preferential formation of phenolic compounds and preservation of the methyl group.

The introduction of light elements into the interstitial sites of metals can significantly modify their surface structure and electronic properties and thus enhance the catalytic performance. However, it is still unclear how the interstitial light elements promote the catalytic activity. Herein, N atoms are incorporated into the bimetallic CoMo system to synthesize Co3Mo3N as an efficient catalyst for reverse water–gas shift (RWGS) reaction. Compared to CoMo, Co3Mo3N significantly promotes the catalytic performance, where the removal of O-containing intermediates is identified as the rate-determining step. The enhanced activity is attributed to the dual functions of interstitial N atoms in Co3Mo3N, which provide additional sites for supplying H atoms to facilitate the hydrogenation of O-containing intermediates and accept electrons from Mo to weaken the binding ability of Mo to O-containing intermediates. These dual functionalized interstitial N atoms promote the redox cycle during the RWGS process and thus improve the catalytic performance. Our work provides an understanding of the interstitial light element-promoted catalytic performance relationship.

This work investigates the deoxygenation reaction during the decomposition of anisole (methoxy-rich model compound of lignin) over bi-functional catalyst. The bifunctional catalyst consisted of a single metal loaded on an acid support; the active metals, i.e. Ni, Co, Mo and Cu, were loaded at various rates, and the acid support was HZSM-5 zeolite with a Si/Al ratio of 25 (HZ(25)). Experiments were conducted in a bench-scale fluidised bed reactor within the temperature range from 400˚C to 600˚C. Experimental results revealed that the increase in temperature and metal loading promoted the selectivity of BTX fraction. Nevertheless, a simultaneous increase in the yield of carbonaceous deposits was also observed at the expense of liquid fraction, both phenolics compounds (Phs) and aromatic hydrocarbons (AHs). 500˚C was the preferred temperature for BTX production. Ni-loaded HZ(25) catalyst