Nonlinear Regression Analysis of the Adsorption of Basic Green-5 from Aqueous Solutions onto a Low-Cost Biodegradable Adsorbent Material

Abstract

Industrial wastewater containing dyes is a main reason for the pollution of water resources. These dyes are toxic and may threaten ecosystems and the human health and they are resistant to sunlight and to high temperature. Worldwide production of dyes in textile, leather, pharmaceuticals and other large industries such as food, constitutes 10,000 different dyes and pigments with an amount of 8 × 105 tons annually. Nowadays, several physical and chemical methods and technologies are used for the purification process of wastewater before it is discharged to the environment, moreover these methods can be improved. In this study, removal of basic green-5 dye from aqueous solutions by calcined eggshell (ES) through the adsorption process is analyzed. The experiments were carried out at 25, 35, 45oC. Experiments were carried out for four different initial concentration values of the dye. Also, surface fitting plots were created to show the effect of the amount of the eggshell waste, pH and temperature on adsorption. BET surface area and SEM analyzes were performed for calcined ESs. Non-linear regression analysis was applied for Baudu and Fritz-Schlunder Isotherms. Obtained results indicate that the calcined ES can be considered as a good, cheap alternative for this adsorption.