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  The Textile industry is not exactly moisture-retentive, nevertheless some of its branches consume large amounts of water and aqueous solutions in the process of preparing semifinished items and manufacturing ready products.

  One of the recent trends of using water and solutions of different chemical substances is the trend associated with preparing bast fiber materials with the help of physico-chemical methods for treatment by cotton processing equipment as raw material replacing cotton.

  The essense of preparing bast fiber materials is that in order to attach properties ensuring technological process' stability and manufactured product quality to the primary element of these complex-structure materials - elementary fiber- it is required to rid it from accompanying substances.

  They are intended by nature for uniting elementary fibers into bunches of 30-40 filaments, which is not suitable for cotton manufacture equipment where such elementary fibers are processed.

  So, to destroy these bonds of chemical nature and to transform destructed connective substances into a solution, an aqueous solution subjected to electrochemical activation is applied.

  Expediency and convenience of its use lies in the fact that for bast fiber materials which have various initial parameters it is mandatory to use solutions of different chemical activity which can be easily conferred on the solutions through different regimes of their activation.

  Experimental treatment of short fiber with the help of physico-chemical methods using electrochemically activated solutions permitted to eventually produce flax fiber of increased softness and fineness, in other words, using the language of textile manufacturers, to improve spinning qualities of raw material, i.e. to receive thinner yarn with higher content of flax component.

  As compared to technologies of other researchers and manufacturers we succeeded in raising flax embedding by 30-80%, when using electrochemically activated solutions for its preparation, the yarn being twice thinner - with no treatment No.30, with treatment No.65.

  Conducted experiments gave only a vague idea of opportunities of using electrochemically activated solutions in textile industry, reducing application of chemical reagents and simplifying technologies, as well as rendering them ecologically friendly.

  In the process of studying different aqueous systems treated by a diaphragm electrolyzer Uzbek scientists discovered a formerly unknown phenomenon of conserving electrode polarization energy in the form of peri-electrode medium potential energy, essentially modifying its reactional ability in chemical reactions. This phenomenon was termed electrochemical activation of liquid media.

  During electrochemical treatment of an aqueous solution two substances are released; anolyte possessing oxidative qualities, in the anode area, and catholyte manifesting reductive properties, in the cathode area. The degree of aqueous solutions' activation is determined by redox potential (ORP) and the medium's pH parameters. The pH and ORP values were estimated with an EV-74 apparatus.

  The main process taking place in the cathode area is liberation of gaseous hydrogen and alkali; besides, en excessive quantity of hydroxyl ions is formed in catholyte (OH^-). In the process of peroxide bleaching hydroxyl ions enhance hydrogen peroxide decomposition followed by formation of perhydroxyl ions (HO₂) which produce a bleaching effect.

  When pH values are high (10-11) and ORP=-(700-800)mV, a certain amount of hydrogen peroxide and monatomic oxygen is formed thanks to which catholyte possesses a bleaching ability. Besides, catholyte has good dissolving, extracting, chemical-adsorptive qualities, as well as the ability to augment the action of substances dissolved in it.

  Having studied the properties of electroactivated aqueous solutions (EAS), a new method of boil-off and bleaching cotton yarn was worked out, which employed activated water. EAS was produced from tap water with averaged mineralization values ranging from 0,2 to 0,8g/l and T=16-18°C, measured by an firm apparatus.

  To achieve desired ORP and pH values table salt was used. As a result of a solution's activation, catholyte's ORP reaches the value range from -700 to -800mV and pH - that from 10 to 10,5; anolyte's ORP varies from +1000 to +1140 and pH - from 2 to 3.

  Under conditions of a thread factory at the Tashkent Industrial Cotton Association approbation of a newly developed method of boil-off and peroxide bleaching of cotton yarn using activated water was conducted. The approbation was performed on yarn of II teх x3x2 linear density, in three variations; control - on common water; on catholyte; on anolyte.

  The developed method of boil-off and bleaching cotton yarn is meant for periodic processes.

  Parameters of physical-chemical and physical-mechanical yarn properties were determined. Analysis of obtained data indicates:

  1. Application of anolyte in the process of boil-off and bleaching is not expedient since it results in fiber damage and loss of strength.

  2. Optimal catholyte parameters for boil-off and peroxide bleaching are: pH10-11 and ORP - -700 to -800mV.

  3. Application of catholyte for boiling-off cotton yarn leads to 30-40 % capillarity increase and permits to rule out alkaline agents discharge (soda and caustic soda).

  4. Yarn bleaching with catholyte makes possible to reduce stabilizer's consumption by 50-70 % (sodium metasilicate) and achieve whiteness of required standard. At the same time there occurs 14 % strengthening of test bleached yarn in comparison with control, breaking load variation ratio is reduced and yarn elongation increases.

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