RESUMEN
The adsorption efficiency of cheap, ecofriendly, and easily available agro-waste, Trapa natans (Chestnut) and Citrullus lanatus (Watermelon) peels, has been investigated in their native forms (TNAT and CLAN) as well as citric acid impregnated forms (C-TNAT and C-CLAN), respectively, for the detoxification of toxic, deleterious, and carcinogenic Eosin yellow dye (EYD) from wastewater streams. Different operational parameters were optimized for the investigation of isothermal, kinetic and the thermodynamic models. R2 for sportive decontamination of Eosin by citric acid treated adsorbents were close to one, supporting the applicability of Langmuir, Temkin, and pseudo-second-order in this investigation. Maximum sorption capabilities were 222 and 667 mg/g for chemically treated bio-waste C-TNAT and C-CLAN, respectively, reflecting their efficient and promising performance, while Gibbs free energy revealed exothermic and spontaneous adsorption behavior. The kinetic statics for qe (cal) are quite close to qe (exp), indicating the viability and fitness of pseudo-second-order mechanisms. The present study suggests that both citric acid fabricated bio-waste C-TNAT and C-CLAN can be substantially employed to decontaminate persistent organic pollutants, like: Eosin yellow dye from wastewater using green approach to resolve socio-economic problems of developing countries.
Asunto(s)
Ácido Cítrico , Eosina Amarillenta-(YS) , Lignina , Contaminantes Químicos del Agua , Purificación del Agua , Ácido Cítrico/química , Eosina Amarillenta-(YS)/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Lignina/química , Adsorción , Purificación del Agua/métodos , Cinética , Aguas Residuales/química , Termodinámica , Biodegradación Ambiental , Concentración de Iones de HidrógenoRESUMEN
The peels of Trapa natans (TRA) and Citrullus lanatus (CIT), were modified with a variety of chemicals to boost their surface for the optimization of adsorption performance by providing a greater number of additional active binding sites. Citric acid-processed peels (TRAC and CITC) had shown more favorable adsorption performance to eradicate acid violet 7 dye (AVS). Extra and additional active sites generated after chemical processing, including hydroxyl (OH), carboxyl (COOH), amines NH2, carbonyl, and ester (-O-CO-) groups, as evidenced from FTIR and SEM characterizations, may boost the potential of physicochemical integration of adsorbent surface activity in order to promote and encourage the retention of hazardous and risky AVS molecules from the water. The Langmuir isotherm assessed the qmax for the adsorption of AVS on TRAC, CITC, TRA, and CIT to be 212.8, 294, 24.3, and 60.6 mg/g, respectively, whereas the correlation coefficients assessed for both TRAC and CITC were 0.98 and for TRA and CIT were 0.97, closer to unity reflecting monolayer physio-sorption. According to Temkin, the adsorption of AVS on TRAC, TRA, CITC, and CIT gives "BT" values of 1.275, 0.947, 1.085, and 1.211 mg/g, also suggesting physio-sorption. Therefore, chemically modified peels can be employed for detoxification of AVS.