A Promising Low Cost Adsorbent Based on Tea-Waste for Confiscation of Crystal Violet Dye

The goal of the current study is to eliminate Crystal Violet dye from aqueous solutions because it is one of the refractory dye molecules that can linger for a long period in the environment and cause hazardous effects. To potentially adsorb Crystal Violet (CV), a cationic dye from aqueous solution, tea-powder waste (TP) was used. Utilizing FTIR, SEM, EDX, XRD, and TGA analysis, the pore shape, surface characteristics, thermal stability and crystalline character of TP were evaluated. Several operating parameters, including contact time, TP dosage, and original CV concentration, point of zero charge (pH_pzc), solution pH and effect of temperature were examined in the adsorption of CV onto TP. Under ideal conditions of pH 5.0 ± 0.2, 30 min of adsorption time and 100 mg of adsorbent dose, dye concentration 100 mg/L, TP was found to have highest possible adsorption capacity of 200.64 mg g^-1. From kinetics of adsorption analysis it was found to follow a kinetic model of pseudo-second order. The results for CV adsorption onto TP were found to be accurately characterised by the Langmuir isotherm. Increase in the temperature favoured the adsorption of CV on TP and therefore adsorption process was proven to be spontaneous and exothermic. Studies on fixed bed columns were also done. Column analysis demonstrated the TP's applicability to the greater sample volumes. For the elimination of crystal violet from aqueous solution, TP showed great promise as an adsorbent.