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The textile industry is very important because its products are widely used by society, however, this activity has a great contribution to the contamination of water resources due to its effluents that contain large amounts of colorants, among which is the blue of methylene (MB) and methyl orange (MO) that can cause damage to the health of living being. For this reason the present study concerned the removal of these dyes by adsorption using Eichhornia Crassipes (Water lily) with different treatments. The results show that the chemisorption removal process using two sites per dye molecule having an exothermic nature for the water-treated lily and for the NaOH-treated lily is endothermic. The maximum adsorption capacities of 228.9 mg/g for MB (60 °C) and 155.38 mg/g (30 °C) for MO with the NaOH treatment were achieved. The SEM analysis shows that there are significant changes in the surface due to the treatments. The XRD patterns indicate that with the pretreatment with NaOH the crystallinity of WL increases while the treatment with water maintains the presence of amorphous cellulose. In the FTIR spectra, the bands corresponding to different functional groups such as lignin, cellulose and hemicellulose that participate in the adsorption of both dyes are observed.

Co 3 O 4 particles were supported on a series of activated carbons (G60, CNR, RX3, and RB3). Incipient wetness method was used to prepare these catalysts. The effect of the structural and surface properties of the carbonaceous supports during oxidation of benzyl alcohol was evaluated. The synthetized catalysts were characterized via IR, TEM, TGA/MS, XRD, TPR, AAS, XPS, and N 2 adsorption/desorption isotherm techniques. Co 3 O 4 /G60 and Co 3 O 4 /RX3 catalysts have high activity and selectivity on the oxidation reaction reaching conversions above 90% after 6 h, without the presence of promoters. Catalytic performances show that differences in chemistry of support surface play an important role in activity and suggest that the presence of different ratios of species of cobalt and oxygenated groups on surface in Co 3 O 4 /G60 and Co 3 O 4 /RX3 catalysts, offered a larger effect synergic between both active phase and support increasing their catalytic activity when compared to the other tested catalysts.

Pd over TiO 2 (sol-gel and Hombikat uv-100) slurries with and without binders have been deposited on square-channel cordierite honeycombs, and vibration, heat, and abrasion resistance of washcoated minimonoliths have been evaluated. Activity tests were carried out in a microreactor operated at differential conditions. Fresh and used catalyst samples were characterized by elemental analysis, XRD, BET, H 2 -chemisorption, H 2 -TPR, NH 3 -TPD, UV-vis, and SEM in order to assess not only the properties but also the homogeneity of catalyst layers. The results show that washcoat loading and catalytic performance are affected by the kind of binder used in the slurry. Washcoat differences are also found regarding vibration, heat, and abrasion resistance.

Bioremediation is a pollutant removal method that has had a great boom due to the diversity of agroindustrial waste that can be used for this purpose, and that has shown having great efficiency and profitability in the adsorption of heavy metals, such as Pb, Cu, and Co. Based on the above, the present work carried out kinetic and equilibrium studies of bioadsorption of Cr (III) using orange peel (OP) as adsorbent, previously treated with methanol, water, and a water–methanol mixture at different pH (0.91, 1.78 and 2.72), and at 30 °C, finding that the adsorption capacity at equilibrium increases with increasing pH, having a maximum of 55 mg g−1 at pH 2.72—under these conditions, lower adsorption energy was used to remove Cr (III). In addition, it was determined that there are no external mass transfer limitations. An isoelectric point analysis indicated that the adsorption is not carried out by electrostatic forces and a FTIR study of the functional groups of OP showed a decrease in the main functional groups (pectin, cellulose, and lignin, among others), which is directly related to the adsorption capacity of the bioadsorbent.

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En este trabajo se estudió la producción de etanol a partir de jugo de piñas de rechazo (frutos que no cumplen las normas técnicas para su comercialización) del departamento del Chocó. La materia prima se caracterizó y se usó en fermentaciones donde se evaluó el efecto del uso de levadura comercial, la dilución del medio y la adición de suplementos sobre la cantidad de alcohol producido a las 72 h de reacción. El perfil de azúcares y la caracterización bromatológica de esta variedad de piña sugiere que corresponde a un sustrato adecuado para la obtención de alcohol sin necesidad de nutrientes o suplementos adicionales. La producción de etanol utilizando S. cerevisiae fue cercana a los 65 gL-1 en un medio de jugo de piña sin diluir, sin adición de nutrientes y sin control de temperatura (entre 23 y 38 °C) ni pH (entre 4,0 y 4,5) durante la reacción. Bajo condiciones de temperatura (30 °C) y pH (4,5) controlados, el tiempo requerido para alcanzar los mismos rendimientos disminuyó considerablemente (menos de 15 horas). Se espera que estos resultados permitan proponer y desarrollar alternativas para la valorización de los residuos del cultivo de piña de la región y para la disminución del impacto ambiental negativo que representan.