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In this research paper, an eco-friendly extraction process of dyes from Vicia faba L. membranes was developed. In this regard, the influence of independent process factors like the weight of material, the extraction time, the temperature and the sodium hydroxide concentration on the natural dye extraction from Vicia faba membranes was investigated. The optimisation of the extraction conditions and the effect evaluation of the different operating parameters were carried out using a Box-Behnken design under response surface methodology. The optimum conditions were found to be 66 °C, 90 min, 5 g and 0.1628 mol·L−1 for extraction temperature, time, mass of the material and sodium hydroxide concentration, respectively. The efficiency of this extraction process under these optimum conditions was evaluated by measuring the total phenolic content (TPC), the total flavonoid content and the relative colour yield (K/S). In these operating conditions, good fastness ratios were observed for the dyed fabrics. [ABSTRACT FROM AUTHOR]

The Vicia faba membranes are an abundant and a low cost product. In the present research paper, the extracted Vicia faba mucilage was tested as an eco-friendly flocculant for textile wastewater treatment. Its performance as flocculant, in decolorization, chemical oxygen demand (COD) removal and the concentration of total suspended solids was checked. The natural extracted product was characterized using infrared spectroscopy. The total sugars were determined in the extracted product. The effect study, followed by an optimization and modeling analysis, of some experimental parameters on the coagulation-flocculation performance, using Vicia faba mucilage (as a flocculant), combined with aluminum sulfate (as a coagulant), showed that the best conditions for the flocculation process were pH of the effluent about 7, flocculant dose about 6.75 mg/L, flocculation mixing time about 3 min and flocculation mixing speed about 30 rpm, leading to a decolorization equal to 92.32%, COD removal of about 97.52% and total suspended solids of about 15.3 mg/L. A comparison study between the flocculation performance of commercial reagents and the bio-agent showed that the natural product presented a good flocculation performance. [ABSTRACT FROM AUTHOR]

The valorization of a low-cost and an abundant material is a significant work for environmental protection. The objective of this work was to investigate the adsorption of two dyes: Basic Red 46 (BR46) and Reactive Yellow 181 (RY181) onto raw (S1) and modified clays. These modifications were carried out by calcination at different temperature (S2, S3, ..., S9), acidic activation, and acetylation. The surface properties of the adsorbents were characterized by the cation exchange capacity, Fourier transform infrared, and X-ray diffraction analyses. Batch studies were performed to evaluate the effect of the contact time and initial dye concentrations on the removal capacities of adsorbents. Among the kinetic models tested, the adsorption kinetics was best described by the pseudo-second-order equation. The isotherm data fitted well with Langmuir model. The maximum adsorption capacities onto the raw clay (S1), calcined clay at 600°C (S5), acidic activated clay (AC), and acetylated clay (MC) were 2.805, 4.232, 1.968, and 2.756 mmol/g for CI Basic Red 46 and 0.031, 0.030, 0.046, and 0.050 mmol/g for CI Reactive Yellow 181, respectively. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study the influence of bagging deformations caused by stress on the characteristics of certain jersey knitted fabrics. We apply a multidirectional stress on some knitted samples varying in composition, in yarn counts and in some knit parameters. We are interested on the permanent maximum deformation and on the maximum permanent bagging height. Experiments are carried out and we found that the bagging volume depends on the fabric strength properties, yarns count and the knit density, whereas the permanent maximum deformation characterizing the bagging phenomenon decreases when the yarn linear density increase (yarn count decrease) and when the course count decrease. A rheological study shows that the generalized Maxwell model with four parameters fits (represents) the knitted fabric reaction after the application of the multidirectional stress. Also, the statistical study shows that the material composition is the most important parameter on the bagging phenomenon. [ABSTRACT FROM AUTHOR]