Recent Advances in Direct Synthesis of Value-Added Aromatic Chemicals from Syngas by Cascade Reactions over Bifunctional Catalysts

Value-added aromatic monomers such as benzene, toluene, and xylenes (BTX) are very important building-block chemicals for the production of plastics, polymers, solvents, pesticides, dyes, and adhesives. Syngas-to-aromatics (STA) is a very promising approach for the synthesis of aromatic monomers, and is catalyzed via bifunctional catalysts in a single reactor, wherein methanol/dimethyl ether and/or olefins intermediates formed from syngas on metal components are converted into aromatic monomers exclusively on the HZSM-5 by cascade reactions. Since an optimal Fischer-Tropsch synthesis (FTS) temperature of Fe-based catalysts is very close to an aromatization temperature of HZSM-5, Fe-based catalysts have been frequently used/modified for the synthesis of aromatic monomers from hydrogenation of carbon oxides (CO and CO₂ ). The nature of metal components and amounts of Brönsted acid sites on HZSM-5, and their mesoporosity and intimacy, significantly alter the selectivity for aromatics by tuning BTX distibution and catalyst stability. Although many developments have been achieved regarding the STA process in recent years, no reviews have been published in this flourishing research area over the last two decades. Here, the recent advances and forthcoming challenges in the progress of syngas (CO+H₂ ) chemistry and hydrogenation of CO₂ toward the value-added aromatic monomers through cascade reactions are highlighted.

Ru and Ag promoted Co/Al2O3 catalysts for the gas-phase amination of aliphatic alcohols with ammonia

The present paper describes the synthesis of primary amines from long-chain aliphatic alcohols and ammonia using alumina-supported noble metal doped cobalt formulations with moderate cobalt loading (5 wt%).

Effect of hierarchical meso–macroporous structures on the catalytic performance of silica supported cobalt catalysts for Fischer–Tropsch synthesis

A series of meso–macroporous silica supports with the same macroporous diameter but different mesoporous diameters were prepared by introducing phase separation into a sol–gel process and used to prepare cobalt catalysts for Fischer–Tropsch synthesis.

Effects of CO2 on the deactivation behaviors of Co/Al2O3 and Co/SiO2 in CO hydrogenation to hydrocarbons

Different deactivation behaviors of the prototype Co/γ-Al₂O₃ (CoAl) and Co/SiO₂ (CoSi) catalysts under an excess CO₂ environment were investigated in terms of the surface oxidation and aggregation of cobalt crystallites for the Fischer–Tropsch Synthesis (FTS) reaction.

Ordered mesoporous CoMOx (M = Al or Zr) mixed oxides for Fischer–Tropsch synthesis

A superior structural stability of the ordered mesoporous CoMO_x catalysts synthesized using the KIT-6 hard template was observed under the reductive Fischer–Tropsch reaction conditions due to the formation of strongly interacting stable Co₃O₄–ZrO₂ mixed oxides.