Decomposition of dye wastewater by H2O2/Ultrasound

• Main Authors: Tsung-Han Hsieh, 謝宗翰
• Other Authors: Prof.Jia-Ming Chern
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/52961637875360359365

碩士 === 大同大學 === 化學工程學系(所) === 103 === With the rapid growth of industry, many pollutants are directly discharged without proper treatment into rivers and oceans and thus causewater pollutionand environmental stress.In this study,the feasibility of acid dye wastewater treatment by ultrasound combined with hydrogen peroxide is evaluated. The effects of individual and combined treatment and the parameters of reaction kinetics were analyzed and discussed under varying reaction conditions. According to the experimental results, the effectiveness of ultrasound-only or hydrogen peroxide-only treatment is not very satisfactory, but the combined treatment has synergistic effect.The effectiveness ofacid dye degradation increases with increasing ultrasound power, but approaches a plateau at higher power input. The acid dye degrades differently in the presence ofdifferent amounts of hydrogen peroxide and 0.17% hydrogen peroxide was found to bethe optimal dosage. The degradation efficiency of the acid dye is higher in acidic environment. The effectiveness of the dye degradation at pH 2 is 10 times higher than those at pH  4. For different initial dye concentrations, the degradation rate increases with the increase in the initial dye concentration. The effect of reaction temperature on the dye degradation is more comlpicated probably due to reaction mechanism shift with temperature. The optimal 2-h dye conversion in this study was found to be 98% at 50°C and pH 2. Finally, the kinetic analysis showed that the dye degradation was zeroth order at lower conversions and one-and-half order at higher conversions.