Turbidimetric study for the decontamination of paint effluent (PE) using mucuna seed coagulant (MSC): Statistical design and coag-flocculation modelling

Abstract

Recently, advances on the usage of natural coagulants in the coag-flocculation process have attracted increasing interest. Previous research has shown that natural coagulant could enhance the coag-flocculation performance. In this study, the performance of mucuna seed coagulant (MSC) an extract from mucuna seed (MS) for the removal of particle load from paint effluent (PE) was investigated. Response surface methodology (RSM) via center composite design (CCD) was used to optimize three operating variables of coag-flocculation process including biocoagulant dosage, time and temperature while treatment efficiency was determined by measuring particle load removal. Furthermore, the mechanism of coag-flocculation was modelled using adsorption isotherm. The morphological and structural results depict MSC to be a compact network with rounded protrusion which is an indication of good coag-flocculation performance. The optimum dosage, time and temperature were found to be 2 g/L, 20 min, and 318 K, respectively. MSC showed optimal particle load removal efficiency of 89.54%. The particle load removal isotherm model followed the Langmuir model. Therefore, it can be inferred from the study that MSC can be used effectively in coag-flocculation for removal of particle load from paint effluent (PE).