Dye and Industrial Effluent Degradation to Reduce Phytotoxicity Employing Microplasma Technique

Abstract This research focuses on the application of non-thermal plasma for treating industrial wastewater containing organic dyes. The study aims to investigate the degradation efficiency of methylene blue and textile effluent using a Microplasma setup. The experimental setup comprises of a reactor head with capillary needles, argon gas flow, and a high voltage DC power supply. The degradation of methylene blue and textile effluent is carried out at different voltages and time intervals. UV-visible analysis is conducted to measure the absorbance spectra of untreated and plasma-treated samples. The results show a decrease in absorbance with increasing plasma exposure time, indicating a reduction in methylene blue concentration. Higher applied voltages lead to more effective degradation and shorter treatment times. Textile effluent was treated at a high voltage of 20kV, which generated energetic electrons and free radicals. After a treatment period of 75 minutes, the color of the effluent intensified. UV-visible analysis of the textile effluent showed an increase in absorbance spectra with irradiation time, confirming the intensified color. FTIR spectra confirmed the presence of the C = C stretching bond with a carbonyl group (C = O) or a carboxylic acid (COOH). The phytotoxicity of untreated and Microplasma-treated textile effluent was examined by germinating tomato seeds. The results illustrated that the effluent treated for 75 minutes exhibited a higher germination rate compared to the 60-minute treatment. The untreated tomato seedlings remained the same, indicating a reduction in the toxicity of the textile effluent. Overall, non-thermal plasma treatment shows promise for efficiently removing organic dyes from industrial wastewater.