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The exchange of chloride ion by phosphate ions in [Zn-Al-Cl] layered double hydroxide was investigated using X-ray diffraction and infrared spectroscopy. The effects of the pH of the solution containing the phosphate ions on the ion exchange was studied. The best sample in terms of crystallinity, was obtained at pH 8. This sample was further characterized by scanning electron microscopy and microanalysis.Layered double hydroxides (LDH)s, also called anionic clays or hydrotalcite-like compounds 1 , are layered solids which have a stacking of positively charged octahedral sheets. The net positive charge, which is due to substitution of trivalent by divalent metal ions in the brucite-like metal hydroxide M(OH) 2 , is balanced by an equal negative charge of the interlayer solvated anions. The LDH compounds can be represented by the general formula 2 :, where M II = Mg 2+ , Zn 2+ , Mn 2+ ,…; M III = Al 3+ , Cr 3+ , Fe 3+ ,…; X m-= Cl -, NO 3 − , CO 3 2− , … and x varies between 0.20 and 0.33 (refs 3,4 ).These materials have received considerable attention in recent years due to their potential technological applications in various domains such as catalysis, electrochemistry, separation technology, and medicine 5-11 . This attention results from the layered strucLayered Double Hydroxide