Extraction of chlorophyll from red clover advance processing wastewater and its stability study

A method to extract chlorophyll from RCPW was reported. Firstly, organics in RCPW was precipitated by ethanol;secondly, chlorophyll in precipitate was extracted by ethanol, the single factor and orthogonal test were designed to optimize extraction parameters. The results indicated that the optimal ethanol concentration to precipitate organics in RCPW was 30%, solid sedimentation rate was 39.45%;the optimal conditions to extract chlorophyll from precipitate were ethanol concentration 90%, extraction temperature 60℃, extraction time 6h and solid-to-liquid ratio 1∶25 (g/mL) , chlorophyll extraction rate was 1.72mg/g. The stability study showed that the red clover chlorophyll extracted by above method was well resistant to heat and oxidant, relatively stable in weak acid or base environment, improved by Fe2+, but easily degraded on light illumination.