Oxidation of Cu(I) by oxygen in concentrated NaCl solutions—III. Kinetics in a stirred two-phase and three-phase reactor

• Published in: Chemical engineering science Vol. 41; no. 1; pp. 1 - 9
• Main Author: Gaunand, A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1986; Elsevier
• Subjects: Chemistry; Exact sciences and technology; Inorganic chemistry and origins of life; Kinetics and mechanism of reactions; Oxygen; Transition metal Compounds; Univalent metal Compounds; Oxidation; Kinetics; Mixed tank reactor; Saline solution; Acidic solution
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/0009-2509(86)85191-0

A whole set of data on the oxidation of cuprous chloride in a standard stirred reactor is treated using the recent work by Papassiopi and co-workers ( Chem. Engng Sci. 40, 1527 and thesis, Ecole des Mines de Paris) on homogèneous kinetics. The reaction regime is found to be a slow one and HCl and NaCl concentrations, temperature, volume of solution and stirring speed only influence the quantity k L a (mass-transfer coefficient × specific interfacial area) or the oxygen solubility or both. The system Cu(I)/O 2 is then adequate to measure k L a in gas—liquid contactors. The improvement of oxidation when an immiscible organic phase is added may be attributed either to the decrease of the water surface tension or to the formation of “two-phase bubbles“ or “gas—liquid drops”, more unlikely at low stirring speed.