Thermodynamics and kinetics of adsorption of textile dyes on different cellulosic materials

Kinetic parameters and thermodynamics properties are important in both process and equipment design, especially for scale up. Data from previous studies on the technology of adsorption were used. As compared to other treatment methods such as coagulation, flotation, oxidation, and other chemical methods, adsorption technology appears to have better potential in removing color, heavy metals and other toxic substances present in the wastewater due to the following advantages: it requires less land area, has lower sensitivity to diurnal variation; not affected by toxic chemicals; has greater flexibility in the design and operation; and provides superior removal of organic contaminants. This paper discussed and integrated the highlights of several researches on adsorption technology applied to textile wastewater treatment using different cellulosic materials. This also focused on the different types of cellulosic and non-cellulosic adsorbents: corn stalks, bagasse pith, sunflower stalk, bamboo, activated carbon, bentonite, vermiculite, and chitosan, all of which are available in the Philippines. Kinetics of adsorption, equilibrium adsorption isotherm, adsorptive capacity, and thermodynamic properties (enthalphy, entropy and Gibbs free energy) for each type of textile dye on different types of adsorbents, were compared and analyzed for design purposes. In general, this paper presented a comprehensive analysis of the kinetic parameters and thermodynamic properties obtained from results of adsorption studies on various textile dyes using different adsorbents. Specifically, the lecture compared the author's research outputs on adsorption data on corn stalk, bagasse pith, sunflower stalk, bamboo, activated carbon, bentonite, vermiculite, and chitosan. Discussion on how these will be used in scale-up for textile wastewater treatment facilities was also included.