A Research article on Benefits of Glauber's salt in Textile Wet processing
The Buzz word which is dominating the present decade in the textile processing industry is "Environment aspect". We could not survive without eco friendly approach at the same time we could not change the existing textile processing system completely, which is taxing the environment heavily. However, we can modify processes in such a way that causes less pollution load and are reusable. By keeping an eye on this objective, Textile Research and Application Development Centre (TRADC) carried out a study by using Birla's Glauber salt, which is a byproduct of Birla Cellulose's viscose manufacturing process. In this study, emphasis is given on fabric dyeing by using glauber salt and its comparison with common salt and vacuum salt. Moreover, pollution load caused by addition of all salts are comparatively analyzed. After extensive experimental trials, TRADC got positive results not only in terms of environmental issues but also from fabric processing point of view.
The key things like prevention of premature hardness of the dyestuff, low TDS level, less effluent load and better depth of dye shade are achieved during various trials.
In order to understand the depth of the subject, one should understand the basics behind the term "salt" with respect to textile processing.
1.2 Why salt used in Textiles?
Is an interesting and basic question in the area of textile processing, particularly in dyeing. The textile substrate and dye molecule, not necessarily should have of homogeneous characteristics to combine with each other. In such case, we require some catalyst to facilitate dyeing action on fabric. Salt plays this crucial role of catalyst. Salt has an extremely high affinity for water. Broadly speaking, Salt is necessary in three ways, firstly, to drive dye into textile during the dyeing process in textile. Secondly, use of salt leads to maximum exhaustion of dye molecules during dyeing process in textiles. Thirdly it is used as an electrolyte for migration, adsorption and fixation of the dyestuff to the cellulose material.
Glauber's salt is a common name for sodium sulfate decahydrate, Na2SO410H2O; it occurs as white or colorless monoclinic crystals. Upon exposure to fairly dry air it effloresces, forming powdery anhydrous sodium sulfate. Johann Glauber's was the first to produce the salt (from Hungarian spring waters). The naturally occurring salt is called mirabilite. Glauber's salt is water soluble, has a salty, bitter taste, and is sometimes used in medicine as a mild laxative; it is also used in dyeing.
The author is GM, Textile Research and Application Development Centre (TRADC)