Study on the adsorption kinetics of L-citrulline from the pseudo aqueous solution of watermelon rind on ion exchange resin

This study aimed to extract L-citrulline from the pseudo aqueous solution of watermelon rind through the ion exchange process using Purolite® C100 resin. The adsorption kinetics of L-citrulline onto the cation exchange resins was investigated under different experimental conditions including pH, potassium concentration and L-citrulline concentration of initial solution. The UV spectrophotometer was used to determine L-citrulline content at 490 nm before and after adsorption. The initial sorption rate, pseudo-first order, pseudo-second order and Weber - Morris rate constants for different initial concentrations were evaluated and discussed. For the kinetic analysis, the pseudo-second order was suitable to describe the L-citrulline adsorption. Purolite® C100 resin has an saturated adsorption capacity of 79.128 ± 0.523 mg/g and 138.366 ± 0.749 mg/g with the initial L-citrulline concentrations of 600 and 1,200 mg/L, respectively.