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Chitosan was obtained from the alkaline N-deacetylation of -chitin, derived from shrimp shells (SS) collected from the Moroccan coast. Effects of temperature, NaOH concentration and reaction time on the kinetics of deacetylation were studied. The degree of deacetylation (DD = 75%) was obtained at T = 120 °C and CNaOH = 12N in a single step for 6h. It was found, from FTIR studies, that the removal of acetyl groups from chitin occur very fast for the reaction time t < 180 min and then becomes constant after, revealing two steps in the deacetylation of chitin following a first-order kinetics for each of them. The second step is considered the limiting step that has, in the temperature range of 25 – 120 °C and maintained CNaOH = 12N, a low apparent rate constant. The activation energy of this step is about 48.76 kJ/mol. The biopolymer (Chitin and chitosan) produced were characterized by X-ray diffraction.

Calcined eggshells (CES) were tested as adsorbent at a low cost for the removal of phenol from the waste water. The shells of Eggs extracts from waste were washed and then dried at a temperature of 60˚C and finally calcined in an oven at the atmospheric air in several temperatures 200˚C, 400˚C, 600˚C, 800˚C, 1000˚C. The chemical composition of the obtained adsorbs was analyzed by the X-ray diffraction. The isothermal study of adsorption of the phenol was realized for the various adsorbates. It showed that the biggest efficiency of the elimination was attributed to the calcined eggshells to 1000˚C with a percentage that reached 37%. The kinetics of adsorption were described by the first rate model. The intra particular distribution is a significant step in the adsorption process of phenol on calcined eggshells (CES). The separation factor gives a favorable adsorption of phenol on the CES.

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