WATER DECONTAMINATION FROM ETHYLENE-GLYCOL BY HYDROGEN-PEROXIDE CATALYTIC-OXIDATION

In order to select the method of water regeneration from air moisture condensate in a manned enclosed environment, the procedure of water decontamination from ethylene glycol was investigated. The process developed at t 20-22-degrees-C and the following concentrations of C2H6O2 = 0.0125-0.5 mole/1, H2O2 = 1-5 mole/1, and catalyst = 1.7-50 % wt. In the presence of 6.67 g/1 of homogeneous catalyst FeSO4.7H2O, destructive oxidation of ethylene glycol to yield CO2 in the system 0.1 M C2H6O2 + 1M H2O2 proceeded effectively. However, the iron concentration in the decontaminated water exceeded significantly the maximally allowable concentration of iron in potable water as well as in industrial and nonindustrial sewage. Heterogeneous MnO- and PbO-based catalysts provided no more than 20 % ethylene glycol oxidation. Siderite, a natural mineral containing 33 % wt. Fe2+, proved a more effective catalyst of ethylene glycol oxidation. When ethylene glycol and hydrogen peroxide were used at ratios of 1:30 and 1:80 with 5 % wt. siderite, the degree of C2H6O2 to CO2 conversion was 99.2 % and 99.8, respectively.