The influence of ph on the synthesis of mixed fe-mn oxide minerals (1989).

Content Provider	CiteSeerX
Author	Inger, M. H. Eb Schulze, D. G.
Abstract	ABSTRACT: Mn-substituted iron oxides were synthesized atpH 4, 6, 8, and 10 from Fe-Mn systems with Mn mole fractions (Mn/(Mn + Fe)) of 0, 0.2.0.4, 0.6, 0.8, and 1.0, and kept at 50 ~ for 40 days. The Mn mole fraction in goethite was <0-07 at pH 4 but increased to-0.47 at pH 6. Goethite and/or hematite formed in Fe and Fe + Mn syntheses at pH 4 and pH 6 at Mn mole fractions <-0.8, and at Mn mole fractions-<0-2 at pH 8 and pH 10. Hausmannite and jacobsite formed at pH 8 and pH 10 at Mn mole fractions ~>0.4. Inthe pure Mn syntheses, manganite (y-MnOOH) formed at pH 4 and pH 6, whereas hausmannite (Mn304) formed at pH 8 and pH 10. As the Mn substitution increased, the unit-cell dimensions of goethite shifted toward those of groutite, and the mean crystallite dimensions ofgoethite decreased. The substitution of Mn in the crystal structures of iron oxide minerals, particularly goethite,
File Format	PDF
Publisher Date	1989-01-01
Access Restriction	Open
Subject Keyword	Mn Mole Fraction Mn Substitution Fe-mn System Mn Fe Iron Oxide Mineral Fe Mn Mn-substituted Iron Oxide Mean Crystallite Dimension Unit-cell Dimension Crystal Structure Inthe Pure Mn
Content Type	Text
Resource Type	Article