Inversion of sucrose solution by ion exchange

Abstract

Inversion of sucrose solution was studied in a packed column with a strongly acidic cation exchange resin as catalyst. The variables studied were: reaction temperature, feed flow rate, feed concentration, and resin particle size. The inversion reaction can be described as a first order irreversible reaction and experimental results showed that the over-all rate decreases with increasing particle size of resin and increases with temperature. Experiment was performed with 20, 30, and 40% sucrose solutions and it was found that the specific rate constant increases with concentration of the feed solution. From the experimental data the values of specific rate constant, distribution co-efficient and effective diffusivity were estimated by non-linear regression analysis. Distribution coefficient for the system was found to be around 1. For 30% sucrose solution the specific rate constant varied from 0.01148 to 0.73909 min-I in the temperature range of 30 to 70°C. Effective diffusivity varied. from 3.826 x 10-8 to 18.951 x 10-8 cm2fsec for the above concentration and range of temperature. Activation energy and Arrhenius constant for over-all rate and intrinsic rate were obtained. For intrinsic rate they were 24.93 Kcal fmol and 7.657 x 1015 min-! respectively. For 30% sucrose solution the limiting value of over-all activation energy varied from 16.765 to 14.628 Kcal/mol for resin diameter 0.326 to 1.09 mm. It was found that at high space-time mass transfer rate in the liquid film was important. This was of the order of 10-5 cm/sec.