Synthesis of Co (ii) and Zn (ii) complexes of modified and unmodified cashew nut (<i>Anacardium occidentals L.</i>) shell liquid extract

Abstract

Cashew nut shell liquid (CNSL) extract obtained using soxhlet extraction method with acetone as solvent has been used in the synthesis of Co (II) and Zn (II) metal complexes. The CNSL gave a molecular peak ion of 298g/mol-1 on a GC-MS, an indication that cardanol was more prominent than anacardic acid in the obtained extract. Physicochemical parameters such as saponification value (50.30 mgKOH/g), moisture content (5.10), iodine value (241.00 mgKOH/g), ash content (1.30) and pH (6.31) were equally obtained. The metal complexes of Co (II) and Zn (II) prepared with unmodified (UMCNSL) and aniline modified CNSL (AMCNSL) were characterized using UV-visible, FTIR, melting point and electrical conductivity. Some characteristic FTIR bands were observed for AMCNSL, UMCNCL, AMCNSL-ZnCl₂.H₂O (1612cm-1) and AMCNSL-CoCl₂.6H₂O (1612cm-1). The presence of C=N were confirmed in the metal complex of AMCNSL-ZnCl.H₂O and AMCNSL-CoCl.6H₂O but were not present in the UMCNSL-ZnCl.H₂O and UMCNSL-CoCl.6H₂O.