Preliminary Investigation of Kaduna-Grown Cashew Nutshell Liquid as a Natural Precursor for Dyestuffs, Pigments and Binders for Leather Finishing

Abstract

The ever-increasing cost of petroleum based products and the increasing environmental concerns and legislation worldwide are forcing industries to look for inexpensive, renewable, locally available and environmentally friendly raw materials. Cashew (Anacardium occidentale) nutshell liquid (CNSL) is one such material that can be polymerized compared to simple phenols from petrochemicals, which have restrictions. CNSL was extracted from cashew nuts purchased from local farmers in Kaduna, Kaduna state (North of Nigeria) using n-Hexane. The crude extract was analyzed for Iodine Value (88mgI₂/100g), Acid value (141mgKOH/g), Saponification Value (53mgKOH/g), Refractive Index (1.689 @ 25⁰C) and pH (3). The results show that CNSL from the Kaduna-grown cashew nuts is a semi-drying oil and suitable for the synthesis of resins and dyestuff intermediates. It, therefore, has a great potential as a natural precursor for dyestuff, pigments and binders for leather finishing.