Using of fluorinated aluminum silicate in the process coloring of textile materials with pigments

The aim of the work is to search for new drugs and technologies for processing textile materials to achieve high quality products with minimum costs and practical absence of harmful industrial emissions. Studies on the use of insoluble aluminum silicate in practical application in the textile industryare conducted at the Ivanovo State University of Chemical Technology. The experience of using silicates for modifying the properties of wool fibre and purification of exhaust dyeing solutions from direct, active and acidic dyes has been accumulated. The article considers the possibility of using fluorinated aluminum silicate (xAl2O3 * ySiO2 * zAlF3), which is a by-product in manufacture of aluminum fluoride, when coloring textile materials with pigment dyes. The uniqueness of this preparation lies in the fact that fluorinated aluminum silicate combines two fractions: insoluble (silicon and aluminum oxides) and soluble (aluminum fluoride). Aluminum fluoride has a limited solubility in water (0.41% by weight at 25 ° C), but is catalytically active and is used in a number of chemical processes as a catalyst. Due to the presence of water-soluble aluminum fluoride, fluorinated aluminum silicate has an acidic reaction. This powder is finely dispersed and its insoluble part has a white color, so it can be used as filler for blending printing inks and a catalyst for the dye fixing process on the fibre. The color and strength characteristics of the obtained stains convincingly prove that the fluorinated aluminum silicate can successfully replace commercially available catalysts. An additional positive feature is an increase in the shelf life of the finished printed composition. The limited solubility of aluminum fluoride, on the one hand, and its distribution in the structure of insoluble alumina and silicon oxides, on the other, makes the preparation catalytically inactive at room temperature, which positively affects the stability of the ink. Another option for the use of fluorinated aluminum silicate in combination with pigments can be purification of exhaust dyeing solutions. In this case, the high sorption activity of fluorinated aluminum silicate with respect to pigments plays a leading role. If fine dispersed fluorinated aluminum silicate is placed in the aqueous dispersion of the pigment, then, settling, it will capture the dye. Within 24 hours, the dispersion completely discolored. At the same time, the settled powder acquires a pigment tint. The results of the research presented in this paper make it possible to talk about the technological possibilities of using fluorinated aluminum silicate in the coloring of textile materials with pigments in which both its sorption ability and catalytic activity are in demand.

CHITOSAN-TEMPLATED LIGHTWEIGHT SPINEL CoAl2O4 NANOFIBRIL AEROGELS

We present lightweight macro-mesoporous spinel CoAl2O4 nanostructured aerogels derived from water-soluble aluminum-chitosan complexes. Chitosan nanofibrils interact with aluminum ions to swell into hydrogels. The aluminum-induced swelling is extended to dissolve the hydrogels in water to form a homogeneous aluminum-chitosan aqueous solution. The addition of cobalt ions in the aluminum-chitosan liquids which are solidified by lyophilization to generate cotton-like aerogel composites. Uniform incorporation of cobalt-aluminum hydroxide ions onto chitosan leads nanofibrils to serve as a hierarchical template to support mixed metal hydroxides in the aerogel composites. We investigated the thermal removal of chitosan template in the composites to obtain spinel CoAl2O4 aerogels that truly replicate spider web-like fibrillar networks of chitosan template. Enlarged porosity, high crystallinity, and lightweight make the CoAl2O4 aerogels useful as a colorful nano-pigment for magnetic ceramics.