In Turkey, the commercial laundry wastewater is usually discharged to the receiving water bodies and its reuse potential is ignored. This wastewater is grouped into the greywater due to their content of organic and inorganic pollutants. In recent years, the sequential processes have become more preferable in greywater treatment and reuse. In this study, a batch adsorption process was applied for further treatment of commercial laundry wastewater which is also pre-treated by means of the electrocoagulation process. In adsorption, two different composites of waste hazelnut shell derived activated carbons, which are supported with polyaniline (PAn/HS) and polypyrrole (PPy/HS), were used as adsorbents. The efficiency of the process was evaluated by means of an experimental design, and the response surface methodology was applied for this purpose. In the experiment with PAn/HS, the chemical oxygen demand (COD) 75% removal efficiency was accomplished with adsorbent dosage of 0.9 g, at pH 8, with 125 rpm mixing rate and for 77.5 min reaction time. For PPy/HS under the same experimental conditions, the COD removal efficiency was obtained as 20%. The utilization of waste hazelnut shell derived composites as adsorbents for commercial laundry wastewater treatment is a good alternative. The production costs of adsorbents were estimated as 0.70 USD/g and 3.21 USD/g for PAn/HS and PPy/HS, respectively. In terms of the production cost, the PAn/HS composite is approved more agreeable as adsorbents for commercial laundry wastewater treatment.

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It is known that industrial wastewaters containing textile dyes comprise organics that are difficult to bio-degrade and when they are discharged to receiving bodies, they cause serious impacts on environment. Therefore, this kind of wastewaters require advanced treatment besides conventional ones. Adsorption is accepted one of the favorable processes, which can be applied integrative to conventional systems during the treatment of this kind of wastewater. In addition to the effectiveness of the materials to be utilized in the adsorption process, their cost and availability are also very important factors. In this study, the effi-ciency of environmentally friendly, cost-effective powdered graphite in the removal of diazo type textile dye (Direct Red 243) color from aqueous solution by adsorption was investigated. For this purpose, Response Surface Method was applied via Box-Behnken Design and the most effective parameters were investigated in dye adsorption with graphite. Adsorption study was carried out in batch mode and pH (2-10), adsorbent amount (0.1-1.5 g) and time (15-65 min) were designated as experimental parameters. It has been observed that the most effective parameter in color removal of dye was pH and at low values of this parameters the higher efficiencies were obtained. Additionally, it was observed that the increase in the amount of adsorbent increased the efficiency, and time had no significant effect besides two parameters. Almost complete decolorization (98%) was acquired at pH 2 with 1.5 g adsorbent for 40 min of study. As a result of the study, even it is not expanded further applications, the graphite can be effective for anionic dye color removal under acidic conditions by its pristine form.