Naslov
Formation and morphology of struvite and newberyite in aqueous solutions at 25 and 37 °C

Autori
Kontrec, Jasminka ; Babić-Ivančić, Vesna ; Brečević, Ljerka

Izvornik
Collegium Antropologicum (0350-6134) 29 (2005), 1; 289-294

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
struvite; newberyite; precipitation; morphology

Sažetak
The influence of the initial reactant concentrations (ci(Mg)tot = 5.0×10-6 to 5.0×10-1 mol dm-3, ci(P)tot = ci(NH4)tot = 10×10-3 to 5.0×10-1 mol dm-3) and temperature (25 and 37 °C) on the composition and morphology of the precipitates formed in the system MgCl2-NH4H2PO4-NaOH-H2O at initial pHi = 7.40 has been investigated. Precipitation diagrams are presented showing the concentration regions within which different morphologies of solid phase have been formed. The solid phases aged for 24 hours were characterized by means of optical microscopy, FT-IR spectrophotometry, X-ray diffractometry and thermogravimetry. It was found that struvite was a predominant phase formed within the concentration region examined and newberyite was obtained only in the region where pH24h < 6.5. The influence of the initial pH on the formation and transforation of these two compounds were studied in the region 5.0 #pHi # 9.0 and the results are discussed.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Temeljne medicinske znanosti

POVEZANOST RADA