no meaning of selective reaction  the ability of your oxidant to oxide some pollutants upon on the way they react for example the difference between Ozone and OH radical selectivy .

ozone is more selective to the pollutants where it cam react through 3 direct way with pollutants 1- Cyclo addition

2-Electrophilic reactions

3-  Nucleophilic reactions

while, - Indirect reaction of secondary oxidators, such as free OH-radicals which is non selective

here you can know more about reaction mechanism  by opening this site:

http://www.lenntech.com/library/ozone/reaction/ozone-reaction-mechanisms.htm

regards,

Dear Mohamed, did you read the question? I would flag your response.

Dear Lindelani,

The complete oxidation of organics is the oxidation to CO2. The selectivity is equal to the ratio of formed  epoxide to the amount of consumed olefin. The basic criteria is the cost of the product. You also must learn about the conversion, yield per oxidant, turnover number, etc 

Thanks Mohamed.

Dear Yurii

Thank you for the answer. My reaction is the oxidation of a fluorinated olefin (as opposed to a hydrocarbon). Complete oxidation goes to COF2 instead, but I really get the point. Please assist me on this, as for the selective oxidation, why transition metal oxides, for example, are chosen to catalyze the reaction like this? Does it have to do with the mechanism of a reaction OR maybe with the nature of a starting material, its reactivity as opposed to alkanes maybe?

Clarification on this again please:

1.can we use the same catalyst for both complete oxidation and selective oxidation of a certain compound?

2. can we use the same catalyst for selective oxidation of an alkane and an alkene?

You are entering to a rather complex area. The selective epoxidation is one of the hottest area. Here  is my own opinion after 40 years working in this field. You are in the very beginning and you need to learn much. 

Clarification:

1. Definitely not

2. If you mean epoxidation, I would say no.

 "why transition metal oxides, for example, are chosen to catalyze the reaction like this?"

Hydrocarbon oxidation  by O2 or H2O2 are commonly carried out in homogeneous solutions. The transition metal oxides are not the best choice. In the most of cases the oxidation of organics by O2 proceeds via radical chain mechanisms. There is no simple relationship between alkene epoxidation and hydrocarbon oxidation. Perfluorinated organics oxidation has some specific features, but you still need to learn basics of organics oxidation. The best oxidants are O2 and H2O2 (to some extent). You may contact me directly by e-mail.

The relative proportion of the monovalent binuclear (O2-) and mononuclear (O -) to the divalent mononuclear (O 2-) oxygen species available at the surface plays a decisive role. This is in the sense that the more electrophilic the oxygen species (i.e., O2- and/or O -), the more is the tendency of the surface towards deep (total) oxidation activity, and vice versa. A combination of appropriate molecular spectroscopic studies (e.g. ESR and in-situ IR) can help identifying nature of the surface oxygen species as well as their relative abundance.

Best regards,

Mohamed 

In the case of a radical mechanism, it is likely that only a change of catalyst may help. If, however, we may assume that oxidation proceeds as a system of consecutive reactions, one can change the selectivity with respect to intermediates by changing (reducing) the temperature as a function of time (batch reactor) - easy to implement, or as a function of current bed length (fixed-bed reactor) - difficult to implement. It is possible in case of exothermic reaction, as oxidation is. Read about optimal temperature profiles for consecutive reactions.

Regards.

Total oxidation is to convert your reactants to COx

partial is to convert your reactants to any other product

selective= your desire product

factor effect on selectivity:

oxidation state of oxide

coordination of oxide

electrophilic/nucleophilic characteristic of your oxidant

particle size of active sites

dispersion of active site

 Partial oxidation of Fluorinated alkenes easier than complete oxidation. It is much more difficult to oxidate C-F bond than C-H. If you use same oxidizing agent definitely you can fully oxidate alkenes.

Thanking you a lot with the answers. Much appreciated. They are mind enlightening. Dr. Yurii V. Geletii, I am indeed in the very beginning with this. :) In fact, it is my first year PhD. And yes I can see I still have to learn much.

Thanks for availing yourself for the direct contact, I would really like to do that at some stage. With due respect, may I please have your email address.

Kind regards

Lindelani

Dear Lindelani,

I sent you a private message 

Check out this recently publication

Thank you Ahmed.