Algal biochar: A natural solution for the removal of Congo red dye from textile wastewater
Abdul Ahad Khan, Salman Raza Naqvi, Imtiaz Ali, Wasif Farooq, Muhammad Waqas Anjum, Hamad AlMohamadi, Su Shiung Lam, Meenakshi Verma, Hui Suan Ng, Rock Keey Liew
Abstract
The present study was aimed at synthesizing algae-derived biochar to examine its effectiveness and adsorption capacity to remove Congo red dye. The independent variables such as dye concentration, adsorbent dose, and adsorption time were optimized by using a central composite design (CCD). An adsorption experiment was conducted to evaluate equilibrium using a detailed experimental design and characterized through XRD, TGA, SEM, EDX, and FTIR analysis. This paper also focuses on evaluating non-linear adsorption isotherm and kinetics to describe the adsorption mechanism along with applying an Artificial neural network to validate the removal efficiency. The maximum Congo red removal efficiency (96.14 %) and maximum adsorption capacity of algal biochar (186.94 mg/g) were achieved with the optimized parameters of 1 mg/L of dye concentration, 0.1 g of adsorbent dose, and 240 min of contact time. Adsorption behavior was well described by Langmuir isotherm and Pseudo-nth order. A multilayer perceptron (MLP) MLP 2–5–1 structure best validates the response. Overall, the study sheds light that Algal-derived biochar is a potential material for the elimination of Congo red dye and contributes to achieving sustainable development goals.