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India's contribution to the leather industry is 12.9% of the world's total leather manufacture, which produces around 3 billion square feet of leather yearly and provides employment to more than 4 million individuals (Invest India 2019b). The major pollutants present in wastewater discharged from the tanneries are chromium, salts, solids, sulfides, alkalinity, lime, etc. The characteristics of tannery wastewater are high chromium (Cr) concentration (toxic element having an adverse effect on flora and fauna and to the human beings), high BOD and COD, high total dissolved solids (TDS), and high total suspended solids (TSS). Kanpur's leather tanning industries are among the major contributors to river pollution and are classified by the MoEFCC as “Red Category” industries in India (MoEFCC 2017). Untreated or potentially processed effluents have risen to 20 times the number of contaminants, such as cyanide and chromium, in 22 highly contaminated regions of the world. It increases the BOD from 10–190 times, which can destroy human life in the affected region in severe situations. The research conducted by Dandira and Madanhire in 2013 also reported that COD in wastewater discharged via tanneries is in the range of 1000–43000 mg/l, which is 25–275 times greater than normal COD (Chaudhary and Walker 2019).