Adsorption of procion red MX-5B and crystal violet dyes from aqueous solution onto corncob activated carbon

Abstract

Textile and dyeing industries are considered as one of the main water utilizing industries and generate a huge amount of colored liquid effluents in their finishing and dyeing processes. In this paper, agricultural waste corncob has been chosen as a renewable source to produce activated carbon at 400 °C (corncob activated carbon, CCAC) for the removal of Procion Red MX-5B (PR) and crystal violet (CV) from dye-polluted effluent using a batch technique. The efficiency of CCAC in adsorbing CV and PR from the water has been carried out as a function of pH, adsorbent dose, contact time, agitation, and initial concentration. The Temkin, Langmuir, and Freundlich isotherm model equations were investigated to understand the adsorption mechanism of dye molecules. The Langmuir isotherm R2 obtained was 0.9958 for CV and 0.9733 for PR. Maximum adsorption capacity obtained was 2.498 mg/g for CV and 2.86 mg/g for PR. Moreover, a pseudo-second-order kinetic equation with R2 value of 0.9999 was found in this adsorption process. To identify the chemical and morphological characteristics and surface functional groups, nanocomposite of CCAC was characterized using field emission scanning electron microscopy and Fourier-transform infrared spectrophotometry. The obtained results indicate that the prepared CCAC can be used as a promising low-cost dye (CV and PR) removing adsorbent from aqueous solutions.