“…However, phosphate fixation by soils has been widely studied in relation to the adsorption of inorganic phosphates by soils and their mineral components (Beck Copyright @ 1994, The Clay Minerals Society and Riemsdijk, 1979;Goldberg and Sposito, 1985). Several authors have shown the structure of kaolinite (Low and Black, 1948;Haseman et al, 1950), aluminium oxides (Van Riemsdijk et al, 1975;Veith, 1978), and iron oxides (Jonasson et al, 1988;Martin et al, 1988) to be altered by lengthy treatment with dissolved potassium or sodium phosphates, which give rise to crystalline or amorphous aluminium or iron mixed phosphates. By using X-ray diffraction and electron microscopy, Kittrick and Jackson (1954) observed that kaolinite was completely decomposed on treatment with 1 M NaHzPO4 for 31 days.…”