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This study involved preparation of 2-amino-5- mercapto-1,3,4-thiadiazole (AMT) and 2,5- Dimercapto-1,3,4- thiadiazole (DMT) compounds which were identified by its m.p. and FT-IR spectroscopy. Therefore, this book includes modification of the synthetic zeolite (5A) by different compounds ( PbS, PbSn, PbAMT, and PbDMT). These zeolite and modified zeolite surfaces were identified by X-ray Diffraction (XRD), Fourier transformation infrared (FTIR), Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) techniques. The adsorption properties includes a study of the adsorption of Congo red (CR) from its aqueous solution upon the zeolite and modified zeolite surfaces ( ZPbS, ZPbSn, ZPbAMT and ZPbDMT). The influential factors upon the adsorption process were studied which include the effect of initial concentration, temperature, adsorbent weight and contact time for equilibrium. We study contact time and kinetic behavior for Congo red (CR) adsorption with all adsorbent at fixed concentration (40 mg/L), pH =7, particle size ( 150 µm) and different temperatures. The results show that the adsorption capacity for adsorption Congo red dye by zeolite increased with the increase

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Ahmed Al-Juboori, Ph.D., M.Sc. and B.Sc. of Physical Chemistry from University of Baghdad, Iraq. He is currently Lectrurer of Physical Chemistry at Baghdad University, Baghdad, Iraq.

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