| dc.description.abstract |
Synthetic dyes are associated with carcinogenic, toxic, and allergic effects on humans and our
environment. Natural dyes have attracted attention globally because of their non-hazardous nature. Beta vulgaris
(Beetroot) plant wastes such as peels and pomaces are an unexploited resource. The present study involved
solvent extraction of natural dye from B. vulgaris peels and pomace, and its application on cellulosic fabrics
alongside natural mordants (alum and tannic acid) in comparison to metallic mordants (potassium dichromate,
ferrous sulfate, and copper sulfate) to improve the colour fastness of the cotton substrate and establish colour
strength equivalence (ceq) relating to synthetic Reactive Orange HER. In mordanting, the three methods (pre-
mordanting, simultaneous, and post-mordanting) were employed. Response surface methodology and central
composite design were used to optimize extraction and dyeing conditions, namely temperature, M:L ratio, time,
and pH. The optimized extraction conditions were M:L ratio of 1:20 and time of 11 hours. This resulted in a
moderate (40%) yield of natural dye from the plant, proving to be better than conventional methods. Optimized
dyeing resulted in temperature 55′C, time 75 minutes, and pH 6. The CIE L*, a*, b*, C*, and h◦ values were
studied by standard methods. The dyed fabrics exhibited very good to excellent colour fastness test (light,
washing, rubbing, and perspiration fastness) in the range of 4–5 in gray scale. These findings reveal that B.
vulgaris peels and pomace can be potential alternatives to synthetic dyes in the colouration of cotton fabrics |
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