RESUMEN
Textile dye effluents have many deleterious effects; therefore, it is essential to remove before releasing into waterbodies. This study developed a two-step process for decolorization of textile dye using sugarcane bagasse (SCB). The first step of the process involved functionalization of SCB with alginic acid and applying as packing material in column and assessing its performance for adsorptive removal of Drimarene red. The designed column showed 90% removal of the dye in dye-aqueous solution whereas 80% removal in dye-house wastewater. Adsorption capacity was increased at first 10 min and then gradually decreased with time. Breakthrough point was not achieved during the 60 min of experiment. Three non-equilibrium models were applied to understand the column bed properties. In the second step, the adsorbed dye molecules in SCB were degraded using an edible fungus Pleurotus sp. to obtain a dye-free nitrogen-rich bagasse. The fungus-treated SCB showed no residual toxicity and a considerable improvement in nitrogen content (from 0.14% to 0.62%) was noticed after the study of elemental profile. New design of the column bed, the processes of the chemical functionalization of the SCB, and bioremediation of dye treated bagasse through Pleurotus sp. offer a novel solution for efficient and safe disposal of textile dyes. PRACTITIONER POINTS: Two-step process for remediation of a textile dye using an agrowaste and Pleurotus sp. Chemical functionalization of an agrowaste for enhanced dye removal. New process of adsorption-fungal degradation for safe disposal of the dyes. Novel technology for a sustainable use of the agrowaste for environmental safety.
Asunto(s)
Saccharum , Contaminantes Químicos del Agua , Adsorción , Biodegradación Ambiental , Celulosa , Colorantes , Textiles , Contaminantes Químicos del Agua/análisisRESUMEN
A concentration-dependent decrease in growth rate and pigment concentration of the blue-green alga Spirulina platensis was recorded after the exposure to graded (5-40 ppm) concentration of six textile dyes. The profile of vital elements (C, H, N, S) also showed a significant variation due to dye toxicity. The algal population showed up to 50% decrease in protein content after exposure to the dyes. Among the pigments, the dye exposure resulted in > 90% decreases in phycocyanin however, total chlorophyll and carotenoids exhibited up to a 50% decrease compared to control. The findings indicate that the unregulated discharge of textile dyes will directly impact the photoautotrophic organisms leading to ecological imbalance in aquatic ecosystems. Overall observations of the report provide baseline information about the toxicity of textile dyes and giving a better insight into the little-understood mechanisms of dye toxicity.
Asunto(s)
Microalgas , Colorantes , Ecosistema , Spirulina , TextilesRESUMEN
Toxicity of three textile dyes-Optilan yellow, Drimarene blue and Lanasyn brown, was evaluated in a green alga Chlorella vulgaris. The unialgal populations of the alga showed a concentration-dependent decrease in specific growth rate and pigments after exposure to graded concentrations of above dyes. The elemental profile (C, H, N, S) of the treated and untreated cells showed a change which was evident from a significant decrease in the quantity of elements after exposure to the dyes. The observations provide convincing evidence that the textile dyes inhibited the growth, pigment and elemental composition of the algal cells. The findings of the present investigation will contribute to gaining a better understanding of the impacts of textile dyes on ecologically important aquatic organisms.
Asunto(s)
Chlorella vulgaris/efectos de los fármacos , Colorantes/toxicidad , Fotosíntesis/efectos de los fármacos , Textiles , Contaminantes Químicos del Agua/toxicidad , Chlorella vulgaris/fisiología , Agua Dulce , Proteínas/metabolismoRESUMEN
The aim of the study was to assess the potentiality of an agro-waste (sugarcane bagasse) for removal of the textile dye (Optilan Red) using novel column based filtration unit with a packed column of chemically treated sugarcane bagasse. The treated and untreated sugarcane bagasse (biosorbent) were characterized by Fourier transform infrared (FT-IR) spectroscopy. Effect of initial dye concentration on percentage removal of dye, equilibrium adsorption of sugarcane bagasse, kinetic studies, breakthrough point equilibrium and desorption of dye from the column material were studied. An inverse dependence of initial dye concentration on percent removal of dye was observed, whereas the equilibrium adsorption (qe) showed a direct relationship with dye concentration. The time required for reaching breakthrough point was 120 min. Desorption of dye through alkali wash resulted in complete desorption after 1 h washing of the column for its reuse for next cycle. FT-IR analysis shows vibration in valence bands of the hydrogen bond of OH group, and the bands of intra-molecular and intermolecular hydrogen bonds, which results in interaction of treated bagasse with Optilan Red textile dye. The present study showed that more than 93% removal of the dye can be achieved in the concentration range 10-50 ppm (aqueous solution). The removal efficiency of the column remained almost unchanged for the treatment of dye-house wastewater spiked with the dye. The agro-waste based treatment process shows a considerable potential for a low-cost treatment of dye contaminated water.