Toluene methylation using methanol offers a high potential molecular engineering process to produce p-xylene (PX) based on shape-selective catalysts. To further improve the process economics, a novel short process was proposed by reducing the high-energy consumption separation of xylene isomers in existing processes since the PX selectivity of the xylene isomers can be enhanced more than the industrial product quality of 99.7%. The PX selectivity intensification was achieved as a result of decreased contact time by considering factors such as the feed ratio, diluents, temperature, and pressure in a toluene methylation reactor. This proposed short process indicated that the reactor effluent could be purified only through the two conventional distillation towers by removing the methanol recovery and separation of xylene isomers. The raw material utilization, energy consumption, and economic data were also analyzed for the six contrastive cases. The short process using catalyst Si–Mg–P–La/ZSM-5 exhibited the highest effective utilization rates of 96.27 and 95.50% for toluene and methanol, respectively. The short process also showed a good economic value in terms of capital investment and operating costs due to the multistage reactor without benzene byproducts. Thus, the obtained total annual cost (TAC) value of 13 848.1 k$·year^–1 was 68.9 and 87.9% of the two existing processes.

Palladium (Pd) nanostructures are highly active non-platinum anodic electrocatalysts in alkaline direct methanol fuel cells (DMFCs), and their electrocatalytic performance relies highly on their morphology and composition. This study reports the preparation, characterizations, and electrocatalytic properties of palladium-copper alloys loaded on the carbon support. XC-72 was used as a support, and hydrazine hydrate served as a reducing agent. Pd_xCu_y/XC-72 nanoalloy catalysts were prepared in a one-step chemical reduction process with different ratios of Pd and Cu. A range of analytical techniques was used to characterize the microstructure and electronic properties of the catalysts, including transmission electron microscopy (TEM), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma emission spectroscopy (ICP-OES). Benefiting from excellent electronic structure, Pd₃Cu₂/XC-72 achieves higher mass activity enhancement and improves durability for MOR. Considering the simple synthesis, excellent activity, and long-term stability, Pd_xCu_y/XC-72 anodic electrocatalysts will be highly promising in alkaline DMFCs.

High-efficiency production of xylene/trimethylbenzene from benzene/toluene with methanol is a potential way to promote the implementation on the coupled cycle development strategy of petrochemical and coal chemical industry and optimize the resource structure. At the same time, relying on the innovation of catalytic new materials, physical chemistry, intelligent capture technology, process engineering, and other principles and methods, p-xylene (PX) and trimethylbenzene (TMB) with higher added value were prepared by C_6-8~arene methylation, which could elevate the level of methylation field and improve the competitiveness of the industry. This paper focuses on the one-step methylation reaction of benzene with methanol or toluene with methanol to obtain high-purity p-xylene (BM-PX/TM-PX), and the one-step methylation reaction of xylene with methanol to obtain mesitylene (XM-TMB). The methylation reaction mechanism and the preparation strategy of a high-performance catalyst were reviewed. The high selectivity of PX obtained by precisely controlling the pore size and acid site distribution of zeolites was emphasized. Meanwhile, the current research progress of TMB, the kinetic/thermodynamics of the BM-PX/TM-PX, and XM-TMB methylation reaction were described. Based on a literature research and the conclusion of our research group, the mechanism of methylation reaction process was expounded. Finally, the new research direction of catalysts used and reaction process in methylation reaction were prospected in order to guide the rapid development of this field.