Both photo-Fenton oxidation and the combination of aerobic sequencing batch reactor (SBR) + photo-Fenton processes were investigated in a bench-scale study to degrade and reuse a real textile wastewater with Total Organic Carbon (TOC) = 390 mg L-1, Chemical Oxygen Demand (COD) = 1560 mg L-1 O-2 and Escherichia coli = 80000 CFU mL(-1) in further dyeing processes. The independent variables considered for the evaluation of the oxidative process were temperature, H2O2 and Fe (II) concentrations. Required treated water qualities were determined by both RD 1620/2007 (Spanish Normative for wastewater reclamation and reuse) and specific water qualities for internal reuse. The best results were obtained when applying photo-Fenton process as a polishing step, where previous aerobic SBR under 1 day hydraulic retention time (HRT), gave 75% TOC reduction after 25 cycles. The further photo-Fenton process coupled under: ([Fe (II)] = 66.5 mg L-1; [H2O2] = 1518 mg L-1; T = 25 degrees C and pH = 2.7) conditions, achieved final COD and TOC reductions of 97 and 95% respectively. E. coil was fully removed according to specific normative. Finally, in order to accomplish specific water qualities for 100% internal reuse, resultant water was further conditioned by reverse osmosis and reused in bench-scale simulated dyeing processes, providing similar dyeing results in terms of K/S than those obtained by using fresh water.Preprin

Natural fibers have been used as an alternative to synthetic ones for their greener character; banana fibers have the advantage of coming from an agricultural residue. Fibers have been extracted by mechanical means from banana tree pseudostems, as a strategy to valorize banana crops residues. To increase the mechanical properties of the composite, technical textiles can be used as reinforcement, instead of short fibers. To do so, fibers must be spun and woven. The aim of this paper is to show the viability of using banana fibers to obtain a yarn suitable to be woven, after an enzymatic treatment, which is more environmentally friendly. Extracted long fibers are cut to 50 mm length and then immersed into an enzymatic bath for their refining. Conditions of enzymatic treatment have been optimized to produce a textile grade of banana fibers, which have then been characterized. The optimum treating conditions were found with the use of Biopectinase K (100% related to fiber weight) at 45 °C, pH 4.5 for 6 h, with bath renewal after three hours. The first spinning trials show that these fibers are suitable to be used for the production of yarns. The next step is the weaving process to obtain a technical fabric for composites production.

This research focuses on the tribological behavior of high-tenacity polyamide 6 (HTPA6) multifilaments when interacting with ceramic and coated metal parts, employing a custom-designed apparatus created for this study. The variables analyzed included yarn count, the types of ceramic and metallic materials, and the testing speed, whereas other conditions such as initial tension, length of the tested section, repetitions, temperature, and humidity were kept constant. It was observed that both the yarn count and the number of filaments affect the contact surface and pressure, resulting in a reduction in the coefficient of friction with multifilaments with higher counts and number of filaments. In contrast, increased processing speeds result in a higher friction coefficient. Furthermore, the finish of the ceramic surfaces and the lubrication of the yarns are essential factors in lowering the friction coefficient.