Wet Air Oxidation

Wet air oxidation of nitrobenzene enhanced by phenol

“…Shende and Levec (1999) found that the conversion of formic acid was about 11% higher when it was mixed with equal molar of acetic acid under the same operating conditions. Similar evidence was found by Birchmeier et al (2000), who added cellobiose or phenol to solutions containing recalcitrant products of incomplete oxidation and resulted in enhanced oxidation of the recalcitrant low molecular weight acids, and Mishra et al (1995) experienced a similar trend when oxidizing diethanolamine and morpholine. Recently, Vicente and Diaz (2003) found that the degradation rate of thiocyanate was significantly enhanced when simultaneously oxidized together with phenol.…”

Carbon materials and catalytic wet air oxidation of organic pollutants in wastewater

“…A first step towards improved remediation of wastewater was the development and successful application of the Wet Air Oxidation technique (WAO) to treat sewage and other industrial effluents [3,4]. Investment and operation costs of WAO plants, however, are not favourable as WAO employs excessive temperatures between 150 and 300°C and air pressures up to 200 bar.…”

“…WAO performance can be improved by the addition of homogeneous [5,6] or heterogeneous [4] catalysts at subcritical conditions or at severe 'supercritical' operating conditions [7,8]. Alternatively, low temperature oxidation processes replace oxygen by stronger oxidants such as O 3 [9,10] or H 2 O 2 [9,11,12] in combination with an energy input to form reactive OH-radicals [13,14].…”

“…Alternatively, low temperature oxidation processes replace oxygen by stronger oxidants such as O 3 [9,10] or H 2 O 2 [9,11,12] in combination with an energy input to form reactive OH-radicals [13,14]. Several reviews on catalytic and non-catalytic WAO [4,5,[15][16][17][18][19], supercritical water oxidation (SCWO) [7,8,[20][21][22] and advanced oxidation processes (AOP) [23][24][25] are now available in literature.…”

Catalytic Wet Oxidation of Paper Mill Debarking Water: Factors Affecting it

“…Wet oxidation (WO) process, a technique governed by generation of active species at high temperature and pressure such as hydroxyl radicals, is known to have a great potential for the treatment of effluent containing high content of organic matter (chemical oxygen demand (COD) 10-100 g/l), or toxic contaminants for which direct biological purification is unfeasible [2]. WO does not completely oxidize pollutants resulting in the formation of organic intermediates.…”