Methanol to Formaldehyde: An Overview of Surface Studies and Performance of an Iron Molybdate Catalyst

Formaldehyde is a primary chemical in the manufacturing of various consumer products. It is synthesized via partial oxidation of methanol using a mixed oxide iron molybdate catalyst (Fe2(MoO4)3–MoO3). This is one of the standard energy-efficient processes. The mixed oxide iron molybdate catalyst is an attractive commercial catalyst for converting methanol to formaldehyde. However, a detailed phase analysis of each oxide phase and a complete understanding of the catalyst formulation and deactivation studies is required. It is crucial to correctly formulate each oxide phase and influence the synthesis methods precisely. A better tradeoff between support and catalyst and oxygen revival on the catalyst surface is vital to enhance the catalyst’s selectivity, stability, and lifetime. This review presents recent advances on iron molybdate’s catalytic behaviour for formaldehyde production—a deep recognition of the catalyst and its critical role in the processes are highlighted. Finally, the conclusion and prospects are presented at the end.

Effect of Mo Dispersion on the Catalytic Properties and Stability of Mo–Fe Catalysts for the Partial Oxidation of Methanol

Mo–Fe catalysts with different Mo dispersions were synthesized with fast (Cat-FS, 600 r·min−1) or slow stirring speed (Cat-SS, 30 r·min−1) by the coprecipitation method. Improving the stirring speed strengthened the mixing of the solution and increased the dispersion of particles in the catalyst, which exhibited favorable activity and selectivity. The byproduct (dimethyl ether (DME)) selectivity increased from 2.3% to 2.8% with Cat-SS, while it remained unchanged with Cat-FS in a stability test. The aggregation of particles and thin Mo-enriched surface layer decreased the catalyst surface area and slowed down the reoxidation of reduced active sites with Cat-SS, leaving more oxygen vacancies which promoted the formation of DME by the nonoxidative channel.

Photocatalytic partial oxidation of methanol to methyl formate under visible light irradiation on Bi-doped TiO2via tuning band structure and surface hydroxyls

Bi-doped titania is well studied for photocatalytic partial oxidation of methanol to methyl formate under visible light irradiation.

Copper on the inner surface of mesoporous TiO2 hollow spheres: a highly selective photocatalyst for partial oxidation of methanol to methyl formate

To raise the methyl formate (MF) selectivity at high methanol conversion is one of the most challenging topics for photocatalytic partial oxidation of methanol to MF.