Kinetics of the reaction of niobium pentachloride with water vapor

Journal Article · Sun Dec 01 04:00:00 EST 1963 · Canadian Journal of Chemical Engineering

DOI:https://doi.org/10.1002/cjce.5450410608· OSTI ID:4137956

Ingraham, T. R.; Whalley, B. J. P.

When niobium pentachloride is exposed to moist air, hydrogen chloride is liberated and hydrated niobium pentoxide or niobic acid remains. It is believed that the rate of the reaction is controlled by the rate of diffusion of water across a layer of unidentified intermediate product of constant thickness (about 0.2 mm). The constant thickness of the layer is maintained by the spalling and cracking of the product after it exceeds a critical thickness. Since the reaction takes place at an interference between the niobium pentachloride and the layer of intermediate, it is necessary to normalize the results for the decrease in interfacial area as the reaction proceeds. When this is done, the rate of the reaction, expressed in terms of grams of niobium pentachloride reacting per square centimeter of interface per hour, is: Rate = (7.7 ± 0.4) x 10⁴ (p_s/p) exp[(-8.1 ± 0.6) x 10³]/RT.

• Research Organization: Dept. of Mines and Technical Surveys, Ottawa
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-005263
• OSTI ID: 4137956
• Journal Information: Canadian Journal of Chemical Engineering, Journal Name: Canadian Journal of Chemical Engineering Journal Issue: 6 Vol. 41; ISSN 0008-4034
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
AIR
CHEMICAL REACTIONS
DIFFUSION
HUMIDITY
HYDROCHLORIC ACID
LAYERS
NIOBIUM CHLORIDES
NIOBIUM OXIDES
REACTION KINETICS
THICKNESS
VAPORS
WATER