Infrared and Raman spectra of magnesium ammonium phosphate hexahydrate (struvite) and its isomorphous analogues. III. Spectra of protiated and partially deuterated magnesium ammonium phosphate hexahydrate

Influence of airflow rate and substrate nature on heterogeneous struvite precipitation

“…In the 1700-1500 cm − 1 region a broad, weak band is detected that is ascribed to δ H 2 O vibration suggesting the existence of different environments for water molecules. Nevertheless, these experimental data are in full agreement with the recent publications [24][25][26] regrarding infrared analysis of struvite, dittmarite, and newberite.…”

Indications that Amorphous Calcium Carbonates Occur in Pathological Mineralisation—A Urinary Stone from a Guinea Pig

“…The band at 995 cm −1 is due to the anti-symmetric stretching mode (ν 3 ) of the phosphate ion, which is triply degenerate for free phosphates. It has earlier been reported to occur at 1006 cm −1 in magnesium ammonium phosphate hexahydrate (struvite) [33]. There is also a good match of the band frequency for the in-plane bending mode (ν 4 ) of the phosphate group (569 cm −1 ), which has been reported to occur at 571 cm −1 in struvite [33].…”

“…It has earlier been reported to occur at 1006 cm −1 in magnesium ammonium phosphate hexahydrate (struvite) [33]. There is also a good match of the band frequency for the in-plane bending mode (ν 4 ) of the phosphate group (569 cm −1 ), which has been reported to occur at 571 cm −1 in struvite [33]. The minor variances between the band positions and those in literature reports can be rationalized by the coupling with librational modes of water, which occur in this spectral region, as well as additional bands from calcium carbonate and organic compounds.…”

Repeated use of MAP decomposition residues for the removal of high ammonium concentration from landfill leachate

“…2a, the infrared spectrum of the MAP decomposition residues shows a similar shape with that of MAP. However, the characteristic ammonium bands at 1441 cm À1 and 1480 cm À1 and the characteristic N-H band at 3300 cm À1 almost completely disappeared after heating (Stefov et al, 2004(Stefov et al, , 2005, further confirming the effective removal of NH þ 4 from MAP by heating under alkali conditions. XRD analysis indicated that the characteristic MAP crystal disappeared after heating, forming amorphous solids that could be assigned to amorphous magnesium sodium phosphate (MgNaPO 4 (Mathew et al, 1982).…”