Supercritical Water Oxidation (SCWO) has been proven to be a powerful technology to treat a wide range of wastes, but there are few references in the literature about the application of SCWO to chemical weapon agents. In this work, SCWO has been tested to treat a chemical agent stimulant, dimethyl methylphosphonate (DMMP), which is similar to the nerve agent VX and GB (Sarin) in its structure. The experiments were performed in an isothermal tubular reactor with H2O2 as an oxidant. The reaction temperatures ranged from 398 to 633 ℃ at a fixed pressure of 24 MPa. The conversion of DMMP was monitored by analyzing total organic carbon (TOC) on the liquid effluent samples. It was found that the oxidative decomposition of DMMP proceeded rapidly and a high TOC decomposition up to 99.99% was obtained within 11 seconds at 555 ℃. An assumed first-order global power-law rate expression was determined with activation energy of 32.35±2.21 kJ/mol and a pre-exponential factor of 54.63±1.45 s.1 to a 95% confidence level. By taking into account the dependence of the reaction rate on oxidant concentration, a global powerlaw rate expression was regressed from the complete set of data. The resulting activation energy was 42.00±0.41 kJ/mol; the pre-exponential factor was 66.56±0.48 l1.31 mmol.0.31 s.1; and the reaction orders for DMMP (based on TOC) and oxidant were 0.96±0.02 and 0.35±0.04, respectively.

Supercritical Water Oxidation Kinetic Reaction Rate Chemical Agent DMMP Total Organic Carbon

Akzo Nobel Function Chemical bv, “MSDS of Fyrol DMMP,” Safety Data Sheet, 2002, http://www.phosphoruschemicals.com/pdf/fyrol% 20dmmp%20msds.pdf
Ahn SH, Joung SN, Yoo KP, Noh MJ, Han JH, Han SH, Korean J. Chem. Eng., 15(4), 390 (1998)
Anitescu G, Tavlarides LL, Ind. Eng. Chem. Res., 39(3), 583 (2000) 
Croiset E, Rice SF, Hanush RG, AIChE J., 43(9), 2343 (1997) 
Fogler HS, Elements of Chemical Reaction Engineering, Prentice Hall International (UK) Limited, London (2000)
Frisch M, McBrayer R, SCWO Commercialization: Integrating Bench, Pilot, and Commercial-scale Research, presented at the Annual Meeting of the American Institute of Chemical Engineers, Chicago, IL, Paper 128a, Nov. (1996)
Gopalan S, Savage PE, J. Phys. Chem., 98(48), 12646 (1994) 
Helling RK, Tester JW, Energy Fuels, 1, 417 (1987) 
Jin FM, Kishita A, Moriya T, Enomoto H, J. Supercrit. Fluids, 19, 251 (2001) 
Kim YS, Mitton DB, Latanision RM, Korean J. Chem. Eng., 17(1), 58 (2000)
Koo M, Lee WK, Lee CH, Chem. Eng. Sci., 52(7), 1201 (1997) 
Krajnc M, Levec J, AIChE J., 42(7), 1977 (1996) 
Lee JC, J. Korea Solid Waste Engineering Society, 16, 205 (1999)
Lee JC, J. Korea Solid Waste Engineering Society, 16, 205 (1999)
Mizuno T, Goto M, Kodama A, Hirose T, Ind. Eng. Chem. Res., 39(8), 2807 (2000) 
Oh CH, Kochan RJ, Charlton TR, Bourhis AL, Energy Fuels, 10(2), 326 (1996) 
Oshima Y, Hori K, Toda M, Chommanad T, Koda S, J. Supercrit. Fluids, 13(1), 241 (1998) 
Park JH, Park SD, Korean J. Chem. Eng., 19(6), 960 (2002)
Park SW, Yoon JH, Lee H, Korean J. Chem. Eng., 13(6), 640 (1996)
Park TJ, Lim JS, Lee YW, Kim SH, J. Supercrit. Fluids, 26(3), 201 (2003) 
Pisharody SA, Fisher JW, Abraham MA, Ind. Eng. Chem. Res., 35(12), 4471 (1996) 
Tester JW, Holgate HR, Armellini FJ, Webley PA, Killilea WR, Hong GT, Barner HE, ACS Symposium Series, 513, 35 (1993)
Yoo KP, Lim JS, Kim SY, Han JH, Lee YW, Recent Commercial Applications of SFE, SFD, SCWO, SCORR and Nano-Materials in Korea, presented at 11th International Symposium & Exhibiton Supercritical Fluid Chromatography, Extraction, and Processing, Pittsburgh, USA, August (2004)