关键词: 红曲红, 钨酸钠, 过氧化氢, 电流效率, 红曲黄色素

Abstract: Using SBS-g-(AA/StSO3Na)/SBS-g-DMAEMA Bipolar Membrane as a separator between the cathode and anode chambers in the electrolysis cell,the optimum conditions of deoxidization of oxygen in cathode were obtained through orthogonal experiment. Then using tungstate/pertungstate as media to indirect electrooxidate hydrophobic monascus red colorant to prepare hydrophobic monascus yellow colorant in cathode. The experiment results show the average current efficiency of cathode was up to 72.39% under the following conditions:that graphite as electrode,10% sulfuric acid as anode electrolyte,0.5 g·L-1 hydrophobic monascus red colorant solution as cathode electrolyte,tungstate concentration:15 mmol/L,pH:3,flow rate of oxygen:65 cm3/min,electrolyze 2 h under the current density of 5.78 mA·cm-2. The FT-IR and UV-VIS results of electrolysis products indicated the epoxidation of hydrophobic monascus red colorant.

Key words: hydrophobic monascus red colorant, tungstate, hydrogen peroxide, current efficiency, hydrophobic monascus yellow colorant