Skip to Main content Skip to Navigation
Journal articles

Adsorption of ethyl violet dye in aqueous solution by forest wastes, wild carob

Abstract : The adsorption of basic dye (i.e. ethyl violet (EV) or basic violet 4) from aq. solns. onto the forest waste non-modified wild carob (NMWC) was carried out by varying some process parameters, such as initial concn., pH, and temp. The exptl. results showed that an increase in the pH from 2 to 7 led to a strong decrease in the adsorption capacity of the dye (EV) on NMWC, showing the predominance of the dispersion forces compared to the electrostatic interactions, owing to the cationic character of the dye and the pHpzc of the biosorbent (∼6). The adsorption process can be well described by means of a pseudo-second-order reaction model showing that boundary layer resistance was not the rate-limiting step, as confirmed by intraparticle diffusion. In addn., exptl. data were accurately expressed by the Sips equation if compared with the Langmuir and Freundlich isotherms. The high "m" values of the Sips model characterized a multilayer adsorption and the max. amt. adsorbed given by the Sips model was 100.4 mg/g at 20°C, namely close to the exptl. value and increased only weakly with the temp. The values of ΔG0 and ΔH0 confirmed that the adsorption of EV on NMWC was spontaneous and endothermic in nature. The pos. values of ΔS0 suggested an irregular increase in the randomness at the NMWC-soln. interface during the adsorption process.
Complete list of metadatas
Contributor : Laurent Jonchère <>
Submitted on : Tuesday, April 28, 2015 - 3:15:24 PM
Last modification on : Wednesday, January 13, 2021 - 3:12:54 AM



Abdelbaki Reffas, Abdallah Bouguettoucha, Derradji Chebli, Abdeltif Amrane. Adsorption of ethyl violet dye in aqueous solution by forest wastes, wild carob. Desalination and Water Treatment, FHF, 2016, 57 (21), pp.9859-9870. ⟨10.1080/19443994.2015.1031707⟩. ⟨hal-01146563⟩



Record views