Hi, Oxygen oxidation is very clean system. The big disadvantage is that sometimes is not enough because the oxidation power of oxygen is lower than other chemicals. The oxygen alone is used commonly with easy oxidable compounds. One option to increase the oxidation capability is to add some catalyzer. There are a lot of catalyzers developed and you must try to look for some one designed for your reaction (or something similar). A key point to install an oxygenation system is how you will distribute the bubbles in the reactor to improve the reaction surface (I gest your reaction is in liquid phase).
I´m researching about ozone oxidation and ozone combined with other things. Even is more expensive than the oxygen (the main cost in large scale is the electrical power supply to turn O2 into O3 with a spark), it is very usefull because the oxidation power is very high. The advantage is that you can obtain ozone from I´m trying to develop a method to increase a little bit more this oxidation power in order to use ozone to destroy very stable compounds.
Of course, other traditional oxidation technique is with chlorine solutions (sodium hipochlorithe or just chlorine dissolved in water). It is very cheap. It isn´t an environmentally friendly option because if you have organic matter you may create organochlorinated compounds, but perhaps is better than chromium wastes. You must evaluate it.
I´m very interested in this topic so you can ask me about.
Sincerely,
Sergio