Esterification of maleic acid and butanol using cationic exchange resin as catalyst

Dibutyl maleate is a perfumery ester used as an intermediate in the production of paints, adhesives, and copolymers. Esterification of maleic acid and butanol was studied in presence of acidic cation exchange resin as a catalyst. The objective of this work was to test the suitability and efficacy of heterogeneous catalysts such as Indion 225H and Amberlyst-15 in the synthesis of dibutyl maleate. Various parameters deciding the conversion of reaction such as mole ratio, catalyst loading, molecular sieves, speed of agitation and effect of temperature were optimized for the maximum rate and conversion. The activation energy was calculated as 71.5 kcal/mol. Diffusivity value D AB (maleic acid in n-butanol) at 80 ∘ C was calculated as 5.08 × 10 - 10 m 2 / s and effective diffusivity ( D e-A ) was calculated as 5.08 × 10 - 11 m 2 / s . Solid–liquid mass transfer coefficient ( k sl-A ) was calculated as 6.77 × 10 - 6 m/s for the particle size of Amberlyst-15 as 0.5 mm. Graphical Abstract Synopsis. Synthesis of dibutyl maleate was carried out using ion exchange resin as a catalyst. Effect of various parameters on the conversion of reaction like mole ratio, catalyst loading, molecular sieves, the speed of agitation and effect of temperature was studied.