CuInSe2 nanoparticles are prepared using a microwave-assisted solvothermal method with ethylenediamine as a solvent. The morphology of the as-prepared CuInSe2 nanoparticles has been successful manipulated by controlling the morphology of selenium seeds. We achieved this through a systematic treatment of selenium powders before the addition of indium and copper precursors. This pretreatment of selenium powders, under microwave heating, converts the morphologies of selenium seed from spherical to nanorod. As a result, this nanorod morphology of selenium seeds are responsible for the formation of crystalline CuInSe2 particles with rodlike morphology, while the crystalline CuInSe2 particles with platelike morphology are obtained without pretreatment of selenium powders. The XRD data and SEM images show that pure chalcopyrite CuInSe2 particles with good crystallinity are obtained with the pretreatment of selenium and ethylenediamine mixture in the microwave heating for 30 min and followed by further microwave-enhanced reaction with indium and copper precursors for 30 min. We proposed the reaction mechanism based on XRD and SEM data, which includes the intermediate products. The Raman spectrum of the chalcopyrite CuInSe2 nanoparticle shows an intense peak at 175 cm−1 corresponds to the A1 phonon mode of tetragonal CuInSe2 chalcopyrite. The compositions of the products consistent very well with their nominal value are confirmed by energy-dispersive X-ray analysis.

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Activated clay, montmorillonite, and activated carbon were used for the removal of two basic dyes, Basic Green 5 (BG5) and Basic Violet 10 (BV10). Both dynamic and equilibrium data were obtained by the batch technique. The dynamic data indicate that the activated carbon was suitable for BG5 but not for BV10 primarily due to the molecular structure, whereas the montmorillonite was not good for either basic dye due to its low surface area for adsorption. The adsorption process was analyzed in terms of two pseudosteady-state equations and the intraparticle diffusion model. The adsorption isotherms of Langmuir and Freundlich as well as Langmuir -Freundlich types were employed to examine the equilibrium adsorption data. Results show that all the adsorption systems could be ORDER REPRINTS adequately fitted by the Langmuir -Freundlich equation. Thermodynamic parameters were also obtained.

An axial dispersion model for the operation of a fixed-bed adsorber with a linear adsorption isotherm was formulated and sol®ed analytically using the separation of ®ari-ables method. The asymptotic solution for a large Peclet number andror a small operation time was also obtained using two limiting cases. The results can be used to correlate or to predict both the mass-transfer zones and the breakthrough cur®es of a fixed-bed adsorber. Influence of both the Peclet number and the retardation coefficient on the operation of a fixed-bed adsorber was also studied. As an example, the axial dispersion model was applied to the experimental data of the remo®al of phenol from the solution in the acti®ated carbon and the Amberlite resin XAD-4 fixed-bed adsorbers.