Photocatalytic Degradation of Benzene and Toluene in Aqueous Medium

Document Type : Short Communication


1 Department of Chemistry, Indian Institute of Technology (BHU), Varanasi-221005 India

2 Centre for Studies in Science Policy, Jawaharlal Nehru University (JNU), New Delhi-110067, India

3 Department of Chemical Engineering and Technology, Indian Institute of Technology (BHU), Varanasi-221005 India

4 Institute of Environment and Sustainable Development (IESD), Banaras Hindu University, Varanasi-221005, India



The resource intensive human activities (such as mining and extraction of mineral oils for betterment of life and modernization of society) have increased environmental pollution several folds. Products of mining and petrochemical industries are advantageous for the modern society. But waste generated such as BTEX from such industries are carcinogenic, toxic and causes adverse effects on environment and human health. These wastes are classified as hazardous waste which cannot be used further. Pollution of soil-water interface due to the release of hydrocarbons in environment is a major public health concern, and therefore, remediation of these pollutants is needed to reduce risk to human and environment. Various methods such as biological, chemical and physical method are used to degrade these pollutants from wastewater. In the present works photochemical degradation of toluene and benzene in wastewater are studied using activated Carbon−TiO2 composites as catalysts in the presence of UV irradiation in photochemical reactor. Composites are prepared by sol-gel method and further characterized by X-ray diffractometry (XRD), scanning electron microscope (SEM) and Fourier transformed-Infrared spectroscopy (FT-IR). The Photocatalytic efficiencies of the synthesized composites were determined by the mineralization of toluene and benzene under UV irradiation in photochemical reactor.


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