ISOTHERMAL KINETIC STUDY ON REMOVAL OF METHYL RED DYE FROM AQUEOUS SOLUTIONS USING GUAVA BARK

In this work, bark of the Guava tree, Psidium guajava L. was used as adsorbent for removal of synthetic dye, i.e. Methyl Red which has given promising results in industrial application. The present investigation involves an isothermal kinetic study of the use of Guava bark as an efficient, low cost adsorbent to remove methyl red dye from aqueous solutions. Guava bark powder is used as a biosorbent. Methyl red dye concentration is determined in prepared aqueous solutions through absorbance - concentration curve. The structural characterization of Guava bark (GB) powder was done by electron microscopy. The adsorption behaviour of the biosorbent was investigated by performing both kinetic and equilibrium isothermal studies. During study the adsorption conditions were calculated by changing different experimental parameters i.e. agitation time, adsorbate concentration, adsorbent concentration, and pH of the solution. Langmuir and Freundlich adsorption isotherms are plotted for analyzing the percentage of methyl red removal. The adsorption studies fit with Langmuir isotherm. The correlation coefficient value indicates a moderate fit for monolayer Langmuir model. Pseudo second order kinetics found to provide a better fit to the data than pseudo first order kinetics.