Page 151 - Advances in Textile Biotechnology

6

Enzymatic treatment versus conventional
chemical processing of cotton

I. R. HARDIN, The University of Georgia, USA

Abstract: The processes of conventional chemical preparation that
include desizing, scouring and bleaching are compared with those of
fully enzymatic processes that, to date, include desizing and scouring but
not bleaching. Much of the driving force to replace conventional cotton
preparation chemistry has been the belief that enzymatic treatments can
save energy because they operate at lower temperatures, and that the
effluent from enzymatic treatments will be much easier to treat and

clean up. The processes are evaluated with regard to effectiveness on
cotton properties, and environmental and energy impacts, and their costs

and benefits are compared.
Key words: chemical processing, cotton, enzymatic treatment, scouring,
biopreparation, bioscouring.

6.1 Introduction
Over the past 15 years, there has been intense and continuing interest in

the development of enzymatic treatment of cotton fibers and fabrics. The
ultimate goals are to use enzymes to desize the fabric, remove surface
materials and impurities so that water absorption is enhanced, and decolor-
ize the cotton to provide either a white yarn or fabric or a consistent white
base for dye application (Thiry, 2008). Much of the driving force to replace
conventional cotton preparation chemistry has been the belief that enzy-
matic treatments can save energy because they operate at lower tempera-
tures, and that the effluent from enzymatic treatments will be much easier

to treat and clean up. In the past decade, an additional driving force has
been the increasing interest from the consumer in purchasing fabric and
clothing that can credibly be said to be produced by more environmentally
friendly processes than conventional products. To be successful in convinc-
ing textile wet processors to switch from conventional to enzymatic pro-
cesses the latter must be shown to be simple, of equal or lesser cost, it must
be demonstrably less difficult to treat the effluent, and the same or better

quality fabric must be produced (Kuildred, 2006).
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