Application of Prunus amygdalus By-products in Eco-friendly Dyeing of Textile Fabrics

Natural dyes have become an interesting subject of study because of their better ecological properties in comparison to their synthetic counterparts.This article concerns the dyeing of wool,silk,and polyamide fabrics with natural dyes extracted from almond shells and stems.The developed method of dyeing by these extracts is interesting and very attractive for several reasons:firstly,the extracts used are the black liquor discharged from the industries of delignification,which is a chemical process for removing lignin from agricultural wastes to produce a cellulosic fiber;(ii)these natural dyes are renewable and available in large quantities;(iii)this method is economical;and(iv)lastly,the dyeing performances of the obtained dyed textiles are very promising.The color of each dyed material was investigated in terms of the CIELAB coordinates and their fastness properties measured by washing,rubbing,and light.

A Challenging Approach to Improve the Low Affinity of Acrylic Fibres to Be Successfully Dyed with a Bio-Colorant Extracted from Grape Marc

Acrylic fibres are highly crystalline and non-polar polymers,which makes their dyeing a very difficult step that poses real technical challenges.In order to overcome this concern,it is intended in this paper to modify acrylic fibers by different methods namely cationisation using the Crosscolor DRT then amidoximation using hydroxylamine hydrochloride and ammonium acetate.The resulted samples were dyed then with the bio-colorant extracted from grape marc.The effect of the pretreatment on fibers fine structure using X-ray diffraction and the scanning electron microscope(SEM)images and its correlation with the colour strength of the dyed fabrics was investigated.The dyeing parameters,such as dye bath pH and temperature on the performances of this dyeing process were studied.Good dyeing qualities and new shades varying from brown to grey and dark green have been obtained following process optimization,mordanting and modification of acrylic fibers by the technique of cationisation.

Structural Characterization and Antioxidant Activity of Lignin Extracted from Ficus Carica L.

The most abundant phenolic biopolymer in the biosphere is the lignin.This phenolic biopolymer commonly exists in combination with polysaccharides and other cell wall components.In this study,the solvent system dioxane-water is used to extract lignin,which is considered as unaltered native lignin.The dioxane lignin extracted from fig stems was characterized regarding to its structural feature,quantification of its functional groups,molecular weight,and evaluation of its thermal properties.Purity and molecular weight distribution of the studied lignin indicated that isolated lignin contained a low amount of sugar(c.a.19%)and had a high weight-average molecular weight(10068 g.mol-1).Lignin sample had approximately the same amounts of guaiacyl(G)and p-hydroxyphenyl(H)units with relatively fewer syringyl(S)units.The isolated lignin revealed good antioxidant properties.Therefore,it proved to have a high potential of application in new antioxidants formulations.

Experimental evaluation of eco-friendly flocculants prepared from date palm rachis

Sodium carboxymethylcellulose （CMCNa） is an anionic water soluble polyelectrolyte widely used in many industrial sectors including food, textiles, papers, adhesives, paints, pharmaceuticals, cosmetics and mineral processing. CMCNa was produced by chemical modification of cellulose, and represents many advantages： natural, renewable, non-toxic and biodegradable. In this study, different kinds of CMCNa, prepared from an agricultural waste date palm rachis, were tested as eco-friendly flocculants for drinking water treatment and their performances as flocculants in turbidity removal enhancement were assessed. The prepared materials were characterized by the degree of substitution （DS） and polymerisation （DP）. The study of the effect of some experimental parameters on the coagulation-flocculation performance, using the prepared materials combined with aluminium sulphate （as coagulant）, showed that the best conditions for turbidity treatment were given for pH 8, coagulant dose 20 mg/L, flocculant concentration of 100 mg/L and stirring velocity （during the flocculation step） of 30 r/min. Under the optimum conditions, the turbidity removal using CMCNa, prepared from raw material, was about 95%. A comparison study between the flocculation performance of a commercial anionic flocculant （A100PWG： polyacrylamide） and that of the prepared CMCNa showed that the performance of the waste-based flocculant with a DS of 1.17 and a DP of 480 was 10% better than that achieved by the commercial one.