Qualitative treatment of catalytic hydrolysis of alkyl formates

Liquid-phase hydrolysis of alkyl formates was performed in a stirred batch reactor using formic acid as a homogenous catalyst, cation exchange resin as heterogeneous catalyst and an additive as a complexation agent. The catalysts increased the rate of the reaction considerably, but the equilibrium conversion was slightly suppressed by the homogenous catalyst. The additive not only accelerated the reaction rate, but also improved the yield significantly. The effect of external and internal mass transfer limitations present in the heterogeneous reaction steps was investigated and it was observed that there is the existence of internal diffusion limitation for the largest catalyst particles. Other parameters such as temperature, catalyst pre-treatment, catalyst loading and stirring speed were investigated in order to optimize the process. The experiments also demonstrated that the ion exchange resin can be reused more than once.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (80 K)Download as PowerPoint slideResearch highlights▶ Formic acid increases reaction rate but suppresses yield slightly. ▶ The additive, X increases both reaction rate and yield. ▶ Internal diffusion is present in the large particle of the resin. ▶ The catalyst can be used more than once.