Cleaner Production of Acetals/Ketals Using a Phosphorus‐Doped Biomass‐Based Carbon Catalyst via Acetalization Reaction

The transformation of aldehydes and ketones into acetals and ketals has garnered significant attention due to their wide applications as fragrances, bio‐oil additives, and organic synthetic intermediates. Conventional acetalization methods, however, often rely on corrosive acids or stoichiometric additives, necessitating harsh conditions and increasing production costs. Here, the development of a phosphorus‐doped carbon catalyst is presented, that enables the acetalization of aldehydes and ketones into acetals and ketals under mild conditions (e.g., 60 °C, atmospheric pressure). This catalyst achieves a high yield of 2‐phenyl‐1,3‐dioxolane (87.1%) from benzaldehyde and exhibits exceptional stability, operating continuously for 120 h in a continuous fixed‐bed reactor. In the continuous reaction, the yield of 2‐phenyl‐1,3‐dioxolane remains over 96% in the first 18 h and slightly decreases to 86% after 120 h of continuous operation. Comprehensive physicochemical characterizations reveal that phosphorus acts as a Lewis acid sites and plays a critical role in modulating the Lewis acid sites of the PC catalysts. This work highlights the significance of optimizing acid properties for the efficient acetalization reaction, offering a promising approach to sustainable chemical synthesis.