Simultaneous aqueous two-phase flotation of sodium chlorophyllin and removal of sugars from saponified solution of bamboo leaves

Abstract

An ethanol–tripotassium phosphate aqueous two-phase flotation (ATPF) system was first time studied for the separation of sodium chlorophyllin and sugars. The single factors influencing the recovery of sodium chlorophyllin in the top phase and removal of sugars in the bottom phase were investigated and optimized by response surface methodology (RSM). The maximum recovery percentage (88.28%) of sodium chlorophyllin were obtained at 0.55g/mL of tripotassium phosphate, 25mL/min of nitrogen flow rate, 26min of flotation time and 5mL of ethanol, meanwhile, the removal percentage of sugars reached 95.84%. Compared with aqueous two-phase extraction (ATPE), ATPF showed advantages of low consumption of organic solvent, high enrichment factors, and high separation effect. Sodium chlorophyllin were demonstrated theoretically and experimentally to have surfactivity. Finally, the scale-up experiments were conducted to further prepare sodium copper chlorophyllin, and the absorbance ratio (A406.00nm/A631.00nm) was 3.49. This method may blaze the trail for mass production of sodium copper chlorophyllin in industry.