Ion exchange properties of zirconyl phosphates—I

A Simple and Rapid in situ Preconcentration Method for Trace Ammonia Nitrogen in Environmental Water Samples Using a Solid-Phase Extraction Followed by Spectrophotometric Determination

“…[1][2][3][4][5][6] Because of the low sensitivity of these methods, preconcentration methods using solid-phase adsorbents such as zeorite, 7,8 hydrous titanium dioxide, 9 zirconium phosphate, 10,11 and copper zirconium phosphate 12 have been developed for the determination of ammonia in water. Recently, a solid-phase extraction of ammonia as indothymol blue using a C18 membrane has also been done followed by its determination by diffuse reflectance spectroscopy.…”

On the Synthesis of α-Zirconium Phosphate

“…The literature reports that amorphous gels are obtained by the rapid addition of ion phosphate containing solutions to zirconium(IV) salt solutions . If the molar ratio of phosphate to zirconium is less than two, quantitative precipitation of the zirconium still occurs (unless the ratio is less than one), but the product is a hydroxyphosphate. , Even when the ratio of phosphate to zirconium exceeds two in the initial mix, the precipitate which first forms has a ratio lower than two . If the precipitate is aged in the mother liquor, its phosphate content continues to increase with time until equilibrium is reached .…”

Structure of zirconium phosphate gels produced by the sol - gel method

“…The layers are packed into blocks, so that they form the structure of a monoclinic lattice with the following cell dimensions: a = 0.9097 nm, b = 0.5307 nm and c = 1.6284 nm; β = 111.38 • . The amorphous and semicrystalline ZrP gels have been considered by some workers [2,8] to be formed from small crystalline α ZrP particles, and others [9][10][11][12][13] refer to them as polymer formations. The selective sorption properties of ZrP gels are affected by the crystallinity and degree of dehydration of the material [2,8,[13][14][15][16][17].…”