JODHPUR : Indian Institute of Technology Jodhpur’s researchers have developed a two-step approach for textile industry-based wastewater recovery. The treatment includes the electrochemical processing of the sample in the first step, followed by the real time photocatalytic degradation using novel ZnO caterpillars outgrown over carbon nanofibers in the second step. This technology possesses several advantages, reducing the constraints of each process when applied separately, along with the complete degradation of pollutants, and no secondary pollution. The coloured waste water emerged from textile industries can be processed with the explored technique and re-used the treated water for various other purposes.
A wide range of synthetic dyes released by the textile industry endangers human and environmental health. Even trace amounts of synthetic dye in water are easily visible and toxic to human health. Therefore, there is a need for innovative treatment techniques that can result in the destruction of dye molecules in wastewater.
Dr. Ankur Gupta, Assistant Professor, Department of Mechanical Engineering, IIT Jodhpur along with his research scholars Mr. Gulshan Verma and Mr. Prince Kumar Rai, and Prof. Jan Gerrit Korvink and Dr. Monsur Islam from Karlsruhe Institute of Technology, Germany, found out this two-step process for treating textile wastewater before discharging them into natural water bodies.
The findings were published in Materials Science and Engineering Journal (https://doi.org/10.1016/j.mseb.2022.116078).
Talking about the need of the research, Dr. Ankur Gupta, Assistant Professor, Department of Mechanical Engineering, IIT Jodhpur, said, “We need to think about recycling the wastewater & reusing the water wherever possible.”
There is an escalating need to address the problem associated with the contaminated water which is the consequence of a huge number of steel and textile industries that release a large amount of polluted wastewater. Degradable organics, heavy metals, dyes, surfactants, and pH-controlled chemicals are among the contaminants found in textile effluents (TEs). Textile industries, as one of the major consumers of water resources, produce wastewater with complex compositions, including toxic compounds, turbidity, high color, inorganic and organic compounds. In general, the type and quality of TEs (reactive dyes) used to produce complex wastewater with a high risk of contamination and coloration. Most of the conventional procedures (precipitation, ion exchange, membrane filtering, etc.) are proving ineffective due to the wide variation in the composition of textile wastewater. Therefore, there is a need for an alternate solution to overcome this problem.
The uniqueness of the research and its salient features are as follows:
Ø The integrated process provides the high organic matter removal efficiency with better reduction of harsh colours present in the real textile samples.
Ø A facile fabrication approach is used to produce ZnO caterpillars outgrown over carbon nanofibers on Si substrate using vapor-liquid-solid method.
Ø A real time textile wastewater degradation is monitored using the IoT technique by integrating a NodeMCU microcontroller board and a pH sensor.
The photo-catalytic decolorization process takes ~240 min to transform the greenish yellow textile effluent to colourless (~99.1%). Additionally, significant amounts of TSS (~75%) and TDS (~80%) were removed from textile wastewater with integration of electrochemical and photocatalytic degradation processes. Further, the hydrophobic nature (CA:130.35̊) of the fabricated ZnO caterpillars and electrochemical processing together has opened a new avenue for exploring and further utilizing for industrial wastewater treatment. As per the researchers the laboratory-based proof-of-concept can be scaled up to process industrial released effluents and remediate wastewater.
