By-product utilisation has been recognised as a promising cleaner technology has attracted intense
attention from both academic and industrial fields in the last decade. Industrial society is currently
experiencing constraints imposed by our resource system by improving existing processes or finding
newer way of waste utilisation. Waste and by-product streams from existing industrial sector (e.g. paper
and pulp industry, meat industry) could be used as renewable resources for production of useful artefacts.
This article mainly features recent research progress towards the utilisation of by-product in
leather processing. This study was carried out to evaluate the propriety of using by-product black liquor
from paper and pulp industry as filler in leather processing. Chemical modification of the black liquor has
been performed to sustain a good compatible between the chemicals and also to improve the diffusion of
black liquor into the leather substrate. The modification of black liquor was done by means of pH
adjustment. Effect of filling nature of black liquor on strength property, softness nature, related
morphological changes, and the dyeing property of the leather samples were thoroughly investigated.
The results reveal that chemical composition of black liquor modulated by the pH adjustment was found
to have a strong influence on the overall performance of the leather substrate