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.
order to understand the depth of the subject, one should understand the basics
behind the term "salt" with respect to textile processing.
Why salt used in Textiles?
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)