CONICET | Buscador de Institutos y Recursos Humanos

Crystal violet (CV), a triphenylmethane dye, is a pollutant that is introduced into the environmentmainly as waste from the textile industry. It is also used as mutagenic and bacteriostatic agent inmedical solutions and antimicrobial agent to avoid the fungal growth in poultry feed. The presence ofthis dye molecule in the environment during a large period of time cause disorders in human healthsuch as allergy, cyanosis, and skin irritation. The ingestion of CV is associated with nausea, headache,mental confusion, increase of the heart rate. Therefore, considerable interest in the development ofmore studies regarding the removal of CV from the environment has arisen in the research field.Several operations have been applied in order to remove CV from wastewaters, including biologicaltreatments, coagulation, oxidation, membrane filtration. However, biosorption is an excellentalternative to eliminate contaminants due to it is a low-cost, simple and efficient operation. Withinbiological substrates used for biosorption purposes, bacteria are known as promising biosorbents,since they offer a large area/volume ratio, low cost and relatively simple growth. To date, there arefew studies of biosorption reported in the literature that use biomass of Rhodococcus erytropolis forthe elimination of toxic compounds. In this context, the objective of this work was to study thebiosorption between the aforementioned bacteria and the CV dye, for its removal from aqueoussolutions. The biosorbent was characterized by zero charge point (pHZPC), infrared Fourier transformspectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray scattering energy spectroscopy(EDS). A factorial design 32 was developed to optimize the pH and biosorbent mass. Under optimalexperimental conditions (pH: 9, biosorbent concentration: 12.5 mg), a biosorption capacity of 90 mg/gand a removal of CV of 93% was achieved. Moreover, a kinetic study was performed and the resultsshowed that the removal of the elemental species took place quickly, reaching the maximum responsepractically during the first 90 minutes of contact. These results showed that Rhodococcus erytropolisbiomass is efficient for the removal of CV from aqueous solutions, following the concept of "greenchemistry", by minimizing the use of reagents and the generation of toxic waste to the environment.

enviar mensaje