BIOSSORÇÃO DE CORANTE REATIVO UTILIZANDO CARANGUEJO UÇÁ (Ucides cordatus) JOÃO

Abstract

Bioadsorbents composed by crustacean powder can be used in the unitary adsorption operation with application in the treatment of industrial effluents. These materials are biodegradable, easy to obtain, low cost, high adsorptive potential and can be used as an alternative to the most commonly used adsorbents like activated carbon and silica gel, having high cost. Effluents from textile industries, if not adequately treated, present themselves as a potential risk when released into natural waters, being able to reach reservoirs and water treatment plants, making the treatment the most emergent ecological solution. The use of crustacean processing residues is an alternative to minimize environmental impacts. In this work, the powder obtained from Uçá crab shells (Ucides cordatus) will be used as a bioadsorbent in the removal of the reactive dye blue quimifix bf 115% (Reactive Blue 222) provided by Matesa Têxtil - JP / PB. The dyeing process involves as a final step a washing stage, that removes the excess of the original dye not attached to the fiber in the previous steps and generates an effluent that is harmful to the aquatic ecosystem because it does not allow the absorption of light by the flora and fauna. To obtain crustacean powder, approximately 25 cooked crab shells were used, which were submitted to immersion in aqueous solution with sodium bicarbonate, washing, drying and grinding in a knife mill. The adsorbent material was characterized by granulometric analysis, X-ray Diffraction (XRD), Fourier Transform infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) and Point of Zero Charge (PZC). A factorial planning 22 with three central points was used, varying the pH (5, 6 and 7) and the concentration of the synthetic effluent (20, 50 and 80 ppm); this type of planning allows a significant study with a minimum of experiments, thus saving time, reagents and capital. The adsorbent obtained approximately 92% removal for the lowest level of concentration and pH. According to the literature, materials with a chemical structure similar to cellulose have good dye removal capacity and this work presents itself as an alternative for the aggregation of value to the process of industrialization of crustacean residues.