Integrated Fuzzy AHP-TOPSIS for selecting the best color removal process using carbon-based adsorbent materials: multi-criteria decision making vs. systematic review approaches and modeling of textile wastewater treatment in real conditions

Abstract

ABSTRACT Here, Fuzzy AHP-TOPSIS methodology proposed for selecting the best colour treatment process using carbon-based adsorbent materials. Cost, safety, accessibility, reuse and adsorption capacity were identified as the main criteria for decision making. The priority of the criteria based on the experts’ opinions ordered as accessibility, reuse, adsorption capacity, environment safety, human safety, material cost, equipment cost with BNP = 0.250, 0.217, 0.172, 0.144, 0.105, 0.070 and 0.049, respectively. The consistency ratio was found 0.7% (less than 10%), which was acceptable to prioritise the criteria results. Fuzzy TOPSIS decision matrix with respect to criteria for evaluating the performance of eight carbon-based adsorbent materials in colour removal was formed and adsorbents ranked according to the NCCi as powder activated carbon>granular activated carbon >carbon nano tube >graphene oxide > graphene >reduced graphene oxide >graphite>coal. Finally, the effect of key factors in the treatment of real textile wastewater using PAC was investigated and optimised with RSM-CCF modelling. The optimal value of the parameters for the best productivity (81.60%) were as follows: pH: 3, PAC dose: 9.99 g L−1 and contact time: 83.19 min, respectively. The adsorption equilibrium and kinetic data were fitted with the Langmuir monolayer isotherm model (qmax: 127.431 ADMI/g, R2: 0.999) and Pseudo-first-order kinetics (R2: 0.998). Thermodynamic parameters, i.e. R2 > 0.995, ΔH°> 0, ΔS°> 0 and ΔG°< 0 also indicated colour adsorption are feasible, spontaneous and endothermic in nature.