Mass transfer simulation on remazol brilliant blue R dye adsorption by optimized teak wood Based activated carbon

Abstract

The reactive dye of remazol brilliant blue R (RBBR) can be toxic to aquatic ecosystems and humans. Hence, the objectives of this study were to optimize teak wood-based activated carbon (TWAC) via response surface methodology (RSM) to adsorb RBBR and to simulate the mass transfer process using Polymath software. The optimum conditions in preparing TWAC were discovered to be 470 Watt of radiation power, 6.40 min of radiation time, and 1.48 g/g of impregnation ratio (IR), resulting in RBBR uptakes of 83.97 mg/g and TWAC’s yield of 30.60%. Isotherm study revealed that the adsorption of RBBR onto TWAC was best described by the Langmuir model with maximum monolayer adsorption capacity, Qm of 337.55 mg/g. The kinetic data were best described by the Polymath Mass Transfer (PMT) model where the rate constant, kPTM was found to increase from 4.84 to 5.22 h−1 when RBBR initial concentration increased from 25 to 300 mg/L. The PMT model predicted the adsorption surface area, am to be 940.79 m2/g, which is highly accurate with the actual mesopores surface area of 983.25 m2/g. The RBBR molecules formed an attraction force with TWAC’s surface functional groups through hydrogen bond (cyclohexane), dipole–dipole force (polysulfides and terminal/medial alkyne), and ion–dipole force (phenol and hydroxy group). Thermodynamic parameters of ΔH°, ΔS°, ΔG°, and Ea were computed to be −3.55 kJ/mol (exothermic), 0.07 kJ/mol.K, −24.37 kJ/mol (spontaneous) and 21.23 kJ/mol (physisorption), respectively.