Optimization the dye bioremoval potential of some food waste materials

Dyes are intense colored and complex organic compounds that permanently color the material to which it is applied. Synthetic dyes used in various industrial areas are serious organic pollutants which are discharged to the environment, especially to aquatic areas. These synthetic dyes, particularly used in the textile, pharmaceutical, cosmetics, plastic, leather, paint, paper and food industries, have been extensively studied due to their commercial importance and damage to the environment. These organic pollutants released into the environment harm the living organisms in the ecosystem. Especially the synthetic dyes discharged into the aquatic phase and they damage aquatic organisms due to their toxicity. Therefore, the removal these dyes from water is a great importance. Some different methods, such as membrane separation, fungal decolorization, coagulation, biosorption, chemical oxidation and adsorption are usable for the removal of dyes from industrial residues but these methods (exception adsorption techniques) have possess drawbacks. Among these physicochemical methods, adsorption technique which is ecofriendly method has effective for removal of synthetic dyes from the wastewater because of the cheapest, flexibility, simplicity and ease of process. Many waste materials such as orange peel, blackberry, watermelon peel, melon peel, wheat bran, sunflower seeds, sugar beet pulp, egg shell, mushroom wastes have been used as adsorbent for dye removal. In addition, many parameters such as contact time, initial solution concentration, temperature, pH and adsorbent amount are investigated in the adsorption method. In this study; using the adsorption method, the usefulness of tea waste, banana peel and chestnut peel as adsorbent was investigated for biodegradation of methylene blue and eriochrome black T from the aqueous solution. Also, this study was focused on the effect of parameters such as contact time, solution initial concentration, temperature, pH and amount of adsorbent, which are effective in adsorption of methylene blue and eriochrome black T dyes. Experimental working conditions were designed using central composite design. Experimental working conditions were designed using central composite design and these parameters were optimized. A regression model was derived using RSM to predict the responses and analysis of variance (ANOVA) and lack of fit test was used to check model adequacy. It was observed that the quadratic model, which was controlled and proposed, was originated from experimental design data. According to the obtained results; it was determined that both single and binary interactions of parameters affect the adsorption. It was observed that the adsorption of methylene blue increased with increasing pH value, temperature, contact time and initial concentration and decreasing amount of adsorbent, it was found that the adsorbent capacity of the adsorbents used with increased initial concentration, temperature, contact time, low pH value and decreasing amount of adsorbent increased for the eriochrome black T. Adsorption capacity of adsorbents were found for methylene blue as chestnut shell>tea waste>banana shell, for eriochrome black T banana shell>tea waste>chestnut shell.