Premium
Zum Chemischer Transport ternärer Übergangsmetall‐ und Erdalkaliwolframate MWO 4 mit Chlor
Author(s) -
Steiner Udo
Publication year - 2005
Publication title -
zeitschrift für anorganische und allgemeine chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.354
H-Index - 66
eISSN - 1521-3749
pISSN - 0044-2313
DOI - 10.1002/zaac.200500095
Subject(s) - chemistry , analytical chemistry (journal) , temperature gradient , ternary operation , metal , alkaline earth metal , materials science , environmental chemistry , physics , organic chemistry , computer science , programming language , quantum mechanics
On the Chemical Vapor Transport of Ternary Transition Metal‐ and Earth Alkaline Tungstates MWO 4 with Chlorine The chemical vapor transport of transition metal tungstates MWO 4 (M=Mn, Co, Ni, Cu, Zn, Cd) was investigated in dependence on mean transport temperature (923 K to 1223 K) and amount of transport agent Cl 2 . All tungstates migrate in a temperature gradient ΔT = 100 K from the region of higher temperature to the lower temperature with migration rates of 0.5 to 8 mg/h depending on experimental conditions. The transport behaviour was determined by continuous measurement of mass change during the transport experiments. The results were compared to thermo chemical calculations and the influence of moisture content discussed in detail. MgWO 4 migrates under the influence of Cl 2 in a temperature gradient 1273 K to 1173 K (migration rate 0.7 mg/h), CaWO 4 and SrWO 4 in a temperature gradient 1423 K to 1323 K (migration rate <0.1 mg/h).