| Areca-boiled water is a kind of organic acid wastewater, which is high concentration, high chromaticity, and low bio-degradability. Currently, there are few special studies on areca-boiled wastewater treatment in the domestic and foreign research. There is sporadic coverage of treatment for comprehensive wastewater from areca processing. There were only o bit of coverages of treatment for comprehensive wastewater from areca processing, but not specially researches of the craftwork. However, extensive application was hindered by complicated operation and extraordinary cost in areca processing wastewater treatment. In this research, based on the refractory composition contained in areca wastewater contain leading to descending of the biodegradability, and in order to investigate the effective components inhibiting the growth of microorganisms in the areca wastewater. It is to investigate the mechanism of utilizing the Fenton reagent oxidation process to treat the areca wastewater and provide new ideas and design basis by using the Fenton reagent oxidation process to treat the areca wastewater, the response surface method to optimize the process conditions, and the combination technique of the LC and MS to measure the chemical compound in the simulated wastewater dealed with Fenton reagent oxidation process.(1) Liquid Chromatography conditions of epicatechin and rutin was explored by HPLC, and determination of epicatechin and rutin.The conditions of HPLC was runned with the method of the methanol and 0.1% phosphoric acid solution as the mobile phase,the gradient elution procedure was:Omin:20% B,8min:100% B,9min:20% B, 10min:20% B, detection wavelength of 236nm, the column temperature was 40?, the flow rate of 1.0mL/ min, the injection volume was 10ul.In this condition, epicatechin and rutin can be well separated. The linear regression equation of determination of epicatechin and rutin was y=5.6126x-0.1248 and y=12.237+0.2929 (R2=0.9997, R2=0.9994).The average recoveries were 99.1% and 101.6%, and the RSD of precision were 1.7% and 1.9%. The retention time of epicatechin and rutin were 7.56min?8.82min.(2) Fenton reagent oxidation technology has strong oxidation ability, and easier to control the reaction conditions, and the TOC and COD in a simulated wastewater can be removed. The Fenton process was used to treat the simulated wastewater contained the epicatechin to find out the optimal crafts conditions with the TOC and COD removal rate as an indicator. Based on Box-Behnken response surface methodology, the primary focus of this paper is to evaluate simple and combined effects of the initial pH value, H2O2 dosage, FeSO4 dosage and the reaction time, establish a mathematical model between TOC removal rate and the above influence factors, and optimize the removal efficiency in Fenton process. When the condition of the concentration of epicatechin in the simulated wastewater was 200mg/L, and then put the simulated wastewater 200ml in the beaker to carry out Fenton reagent oxidation technology, it indicated that when the condition was the initial pH value 4, H2O2 dosage 7.5 ml/L, FeSO4 dosage 1.25 g/L, the reaction time 120 min, and the PAM dosage 0.2%,the removal efficiency of TOC was 65.22%. Through the response surface conclusion made by Box-Behnken, the combined effect of initial pH value, FeSO4 dosage was significant. Additionally, the effect of H2O2 dosage, FeSO4 dosage and initial pH value on the TOC removal rate was particularly significant. The optimum reaction conditions with the highest TOC removal ratio of 82% were determined to be H2O2 dosage=10.6 ml/L, FeSO4 dosage= 2.25 g/L, initial pH value=4.59, and reaction time=74 min.(3) The Fenton process was used to treat the simulated wastewater contained the epicatechin to find out the optimal crafts conditions with the TOC and COD removal rate as an indicator. Based on the result of Box-Behnken response surface methodology, when the condition of the concentration of rutin in the simulated wastewater was 200mg/L, and then put the simulated wastewater 200ml in the beaker to carry out Fenton reagent oxidation technology, it indicated that when the condition was the initial pH value 4, H2O2 dosage 5 ml/L, FeSO4 dosage 1.5 g/L, the reaction time 120 min, and the PAM dosage 0.5%,the removal efficiency of TOC was 68.3%. Through the response surface conclusion made by Box-Behnken, the combined effect of initial pH value, FeSO4 dosage and the reaction time was significant. Additionally, the effect of FeSO4 dosage, reaction time on the TOC removal rate was particularly significant. The optimum reaction conditions with the highest TOC removal ratio of 74.6% were determined to be H2O2 dosage=1.52 mL, FeSO4 dosage= 0.3 g, initial pH value=3.83, and reaction time=73 min.(4) The Fenton process was used to treat the areca wastewater to find out the optimal crafts conditions with the removal of TOC and COD in wastewater as an indicator. Based on Box-Behnken response surface methodology, the primary focus of this paper is to evaluate simple and combined effects of the H2O2 dosage, FeSO4 dosage, initial pH value and the reaction time, establish a mathematical model between TOC removal rate and the above influence factors, and optimize the removal efficiency in Fenton process. When the condition of the COD concentration of the areca wastewater was 6300mg/L, and then put the simulated wastewater 200ml in the beaker to carry out Fenton reagent oxidation technology, it indicated that when the condition was the initial pH value 5, H2O2 dosage 50ml/L, FeSO4 dosage 12.5 g/L, and the reaction time 120 min, the removal efficiency of TOC was 65%. The combined effect of H2O2 dosage, FeSO4 dosage was significant. Additionally, the effect of H2O2 dosage on the TOC removal rate was particularly significant. The optimum reaction conditions with the highest TOC removal ratio of 70.2% were determined to be H2O2 dosage =54.2 ml/L, FeSO4 dosage= 12.55 g/L, initial pH value=4.98, and reaction time=103min.(5) From the result of using the LC-MS technique to analyze the composition from the simulated wastewater including rutin to be treated by the Fenton reagents, the main way to degradation the rutin was two. The first way was that the rutin was hydrolyzed to quercetin and rutinosein in the condition of acid, and then under the effect of hydroxyl radicals, the hydroxyls was oxidized to keto on the B ring, Further oxidized to small molecule compounds; other way was that the hydroxyl radicals attacked the oxygen atom between the B ring and C ring producing two oxidation, and oxidized to CO2 or small molecule compounds. |
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