Identification of Water Polluting Organic Dyes by Tomato Plant Root and Silica through Adsorption Mechanism from Aqueous Solution

Abstract

The organic dyes directly pollute the soil, water, plants and all living systems in the environment. In which, water polluting dyes are identified through adsorption mechanism by using anionic dyes such as indigo carmine and congo red. For this study, tomato plant root powder and silica are chosen as adsorbents. The adsorption parameters are optimized for maximum adsorption. The positive DSº values for adsorption of anionic dyes indicate that the high disorder at adsorption interface. The DGº values are not much increased with increase of temperature indicates the adsorption is almost over at room temperature. The adsorptions of both dyes are followed Freundlich and Langmuir isotherms and pseudo second order kinetics. The negative values of DHº less than 40 kJ/mol indicated that the adsorption is physisorption. The high recovery of anionic dyes from tomato plant root and silica is a supportive evidence for the water polluting nature of anionic dyes.