The removal of copper (II) and cadmium (II) ions from aqueous solutions, by adsorption on activated carbon prepared from rice hulls (ACRH), was investigated depending on pH, activated carbon dosage, contact time, initial metal concentration and solution temperature. The optimum values of pH, ACRH dosage and contact time were determined to be 5-8, 0.5 g ACRH/25 mL solution an 60 minutes respctively for the adsorption of Cu (II) ions and 5-8, 1.5 g ACRH/25 mL solution and 60 minutes for the adsorption of Cd (II) ions. From the initial concentrations, the constants for the Freundlich and Langmuir isotherm were calculated at 293 K and 313 K. The adsorption of Cu (II) and Cd (II) ions from aqueous solutions was found to be exothermic [ ∆ H • =-13.474 KJ/mol for Cu (II) and ∆ H • =-2.302 KJ/mol for Cd (II)]. Furthermore, the other thermodynamic data for ∆ G • and ∆ S • , were also calculated at 293 K and 313 K.

In this study, the dyeability of polypropylene fibres with a disperse dye via microwave and ultrasonic energy was examined. A dye bath having a liquor-to-goods ratio of 20:1, and including dyestuff 2% owf was prepared and dyeing experiments using microwave and ultrasonic energy were carried out. In the case of microwave dyeing, experiments have been carried out at different energy levels (L, M-L, M, M-H and H) and different time ranges (1 to 5 min) while in the case of ultrasonic energy different temperatures (20, 40, 60 and 80 °C) and different time range (1 min to 30 min) were used. Additionally, effect of carrier was also investigated. Dyed samples were examined by determining their K/S values. Diffusion coefficients in all methods were calculated using Shibusawa's approximation of Hill's equation. Washing fastnesses of dyed samples were also examined. This study showed that the dyeability of polypropylene fibres was increased by both microwave and ultrasonic energy.

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Water hyacinth Eichhornia crassipes was found to have biosorption capacity for cationic dyes, malachite green and methylene blue from aqueous solutions. To evaluate the biosorption capacity and characteristics, the effect of solution pH, initial dye concentration, temperature, dose of biosorbent loading, contact time and shaking rate were investigated in a batch mode. Biosorption was increased with the increasing temperature for both studied dyes. The Langmuir and Freundlich adsorption models were used for mathematical description of the sorption equilibrium. Equilibrium data was fitted well to the Langmuir model in the studied concentrations (1-