Extraction, Characterization and Application of Cashew Nut Shell Liquid from Cashew Nut Shells
Sampson Kofi Kyei *
Africa Centre of Excellence in Oilfield Chemicals Research, Department of Pure and Industrial Chemistry, University of Port Harcourt, Nigeria and Department of Chemical Engineering, Kumasi Technical University, Kumasi, Ghana.
Onyewuchi Akaranta
Africa Centre of Excellence in Oilfield Chemicals Research, Department of Pure and Industrial Chemistry, University of Port Harcourt, Nigeria.
Godfred Darko
Department of Chemistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.
Uche J. Chukwu
Africa Centre of Excellence in Oilfield Chemicals Research, Department of Pure and Industrial Chemistry, University of Port Harcourt, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
In this study, cashew nut shell liquid has been extracted from cashew nut shells using an accelerated solvent extraction technique and was employed as a precursor for the synthesis of cashew nut shell liquid resin. The extract was a dark brown viscous liquid with an average yield of 30.61±0.200%. Results of the physical analysis showed a moisture content of 4.45±0.020% and a density of 0.95±0.300 gcm-3. The percentage brix and refractive index were 76.20±0.001 and 1.47 ±0.010 respectively. Chemical characterization showed a pH of 5.65±0.003; acid value of 8.25± 0.200 mg KOH/g; ash content of 1.80±0.6%; free fatty acid of 4.12±0.400 mg KOH/g; ester value of 247.01±0.100 mg KOH/g and a saponification value of 255.26±0.800 mg KOH/g. The FTIR spectra revealed that cashew nut shell liquid is polymeric. These findings confirm that higher phenolic compounds which can be used as potential precursors in industrial applications could be obtained from agro wastes.
Practical Applications: Cashew nut shell liquid, an extract from cashew nut shell, an agro waste has a wide range of functional products. A practical application is synthesis of a high viscous, flexible cashew nut shell liquid resin with physical properties that are consistent with literature and could also be further used in other industrial applications. Further processing of cashew nut shell for the development of value added products like resin can be a better option.
Keywords: Cashew, food processing, accelerated solvent extraction, resin, phenolic compounds.