Application of microwave-treated Casuarina equisetifolia seeds in adsorption of dyes

Abstract

Microwave-treated Casuarina equisetifolia seeds were used as adsorbents in batch adsorption of malachite green (MG) and neutral red (NR) dyes. Chemical composition analysis show that amount of cellulose in seeds was as high as 56%. The amount of dye adsorbed increased with the increase of initial MG and NR dye concentrations from 42.47 to 51.18 mg/g and 29.78 to 39.66 mg/g, respectively. Surface morphology observation supports the adsorption process and Fourier Transform Infrared Spectroscopy (FTIR) spectra analysis indicates involvement of functional groups in the adsorption process. Langmuir model fitted well the experimental MG adsorption data with R2 of 0.9928. Both Langmuir and Freundlich models were found to have best fit for the adsorption of NR dye with R2 of 0.9611 and 0.9791 respectively. The adsorption factor, RL of MG and NR dyes reveals that the adsorption process is favorable in nature.

Keywords: Casuarina equisetifolia, microwave, adsorption