Adsorption of metal ions and dyes from water by cashew nut testa tannin resin (CATAR) was studied and the effects of temperature, initial pH, initial concentration and time were investigated. Scanning electron microscopy (SEM) and infrared spectroscopy (FTIR) reveal effective adsorption processes. Kinetic studies show that CATAR adsorption is complex and thermodynamic parameters calculated reveal spontaneous and endothermic adsorption of studied pollutants onto CATAR. The use of CATAR as an alternative adsorbent is proposed considering that of simulated wastewaters gave excellent removal performances of 94.0% (Cd ions), 99.4% (Cu ions) and 97.1% (Pb ions) at pH of 6 and 303 K using amount of CATAR. Removal performances obtained for simulated dye wastewaters using CATAR at similar conditions for removal of metal ions gave 71.1%, 79.2% and 86.6%, respectively for crystal violet, methylene blue and malachite green.

Fats and oils undergo hydrolysis reaction. They hydrolyse to yield propane-1,2,3 triol and the corresponding alkanoic acids if it is acid hydrolysis. Alkaline hydrolysis yields sodium or potassium salt of the alkanoic acid and propane-1,2,3-triol. A common approach for bleaching palm oil has been the use of clay materials, particularly the commercially available fuller's earth. In this study, the suitability of chemical bleaching of palm oil using acidified (0.1M H 2 SO 4 ) and non-acidified 1.0M KMnO 4 was examined. This is compared to the adsorptive procedure using clay materials. Average bleaching absorbance values of 0.017+0.005 and 0.115+0.004 for acidified and non-acidified KMnO 4 were respectively obtained from the oxidative bleaching procedure. Those for fuller's earth and its blend with sodium sesquicarbonate (trona, a locally obtained clay) gave absorbance values of 0.121+0.011 and 0.186+0.006 respectively; while that for trona/activated carbon blend was 0.234+0.007. These are in comparison to 0.881 for the unbleached palm oil. Thus, a relatively better bleaching was achieved with the oxidative process. A first order rate reaction with respect to the bleaching agents was obtained for both procedures. Rate constants of 0.079+014 (acidified) and 0.055+0.020min -1 (non-acidified) at 80 0 C were recorded for the oxidative bleaching. These are compared to 0.034+0.009 obtained for the clay mixture. Half-life values of 10min for acidified oxidative process, and 28min for adsorptive clay mixture method, were obtained. Efficiency of 98% was obtained for the acidified oxidative compared to approximately 70% for the clay blend. A significance, p< 0.05, between the absorbance values for the acidified oxidative and each of the adsorptive clay bleaching procedures was obtained.These observations indicate the potentials of oxidizing agents especially the acidified KMnO 4 in the bleaching of palm oil, and therefore, suggest its usage industrially for this purpose.