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1193048 
Book/Book Chapter 
Methylene chloride oxidation and hydrolysis in supercritical water 
Marrone, PA; Lachance, RP; Dinaro, JL; Phenix, BD; Meyer, JC; Tester, JW; Peters, WA; Swallow, KC 
1995 
Yes 
ACS Symposium Series
ISSN: 0097-6156
EISSN: 1947-5918 
ACS SYMPOSIUM SERIES 
608 
197-216 
WOS:A1995BE38K00013 
Hydrolysis and oxidation of methylene chloride (CH2Cl2) in supercritical water were carried out in a tubular plug flow reactor over the range of 450 - 600 degrees C, 4 - 9 seconds reactor residence time, and sub- to superstoichiometric O-2/CH2Cl2 feed ratios, all at a pressure of 246 bar. Major products of both hydrolysis and oxidation were carbon monoxide (CO), carbon dioxide (CO2), formaldehyde (HCHO), methanol (CH3OH), hydrochloric acid (HCl), and molecular hydrogen (H-2), with small amounts of methane (CH4) above 562 degrees C. Trace quantities of one and two carbon chlorinated hydrocarbons were also detected. CH2Cl2 conversions ranged from 26+/-9% to 99.9+/-0.1% over the conditions explored. Conversion under hydrolysis conditions was very close to that under oxidation conditions. The primary effect of O-2 was only to change the product distribution to more CO and CO2 and less HCHO, CH3OH, and H-2 relative to that observed under hydrolysis. Significant corrosion of the Hastelloy C-276 preheater tubing was observed, most likely caused by the presence of aggressive Cl- ions. The experimental evidence suggests a reaction network for CH2Cl2 oxidation that involves reaction with water as a first step to produce primarily HCl and HCHO (and CH3OH at higher temperatures), which are then in turn further oxidized to CO and CO2.