Study On Processing Conditions Of Ion Exchange Chromatography Of Hydrolysis-prepared Inositol

Inositol is a kind of saturated crico-polyol with functions similar to Vitamin B1 and Vitamin H. In this paper, high purity inositol was prepared through acidic hydrolysis of phytin, anion exchange chromatography of the resulting phytic acid, high pressure and high temperature hydrolysis of the eluted sodium phytate solution, resin chromatographic decolorization of the inositol as released, and electrodialytic desalination.The optimum conditions of D318 anion exchange resin chromatography for phytic acid was determined as follows: 16 mg/mL phytin in a pH 2.0~3.0 (achieved by adding concentrated HCl) at a feeding flow rate of 1mL/min for adsorption; and 5% NaOH solution at a flow rate of 2mL/min for desorption. Under this conditions, the dynamic exchange capacity, working exchange capacity and desorption rate of the process were 131.28mg/g, 64.86mg/g and 96.23%, respectively. The optimum conditions were applied on 3 batches of phytin of varying purities and the final yield was all more than 94%. The kinetics and thermodynamics of phytic acid adsorption was found to be an exothermal process with entropy reduction that follows the Langmuir isotherm and correlation coefficient were all more than 0.985; and the adsorption dynamics was in accordance with the second order rate equation and correlation coefficient were all more than 0.99.The optimum hydrolysis conditions of sodium phytate as obtained above was determined via orthogonal experiment: solution concentration increased to 20% by rotary evaporation, hydrolysis pressure 10atm, and hydrolysis time 10h, under which the yield of inositol was more than 80% on average.The sodium phytate hydrolysis solution was decolorized and partially desalinated by D301-F ion exchange resin chromatography with the optimum conditions determined: pH 1.0~2.0, room temperature, flow rate 4mL/min,. The decolorized sodium phytate hydrolysis solution was then subjected to electrodialysis to remove residual salts under the conditions established as follows: concentration of the solution as is, voltage 40V, flow rate 60L/h, and desalination time 21min. The desalination rate and loss rate obtained were respectively 11.26% and 4.13% after the D301-F resin chromatography and 98.51% and 2.71% after electrodialysis. The decolorization rate of the resin was 98.19% and the processing capacity was 2mL/g. The final yield of inositol was 69.58% on completion of electrodialysis, which is higher than that of other procedures reported previously. The infrared spectrum and mass spectrum of the refined inositol was in agreement with that of the standard preparation.