Nitrous catalytic abatement

Figure 7.4 Schematic diagram of the catalytic abatement of nitrous oxide.

Early references to catalytic reactions of nitrous oxide canbe found in a book by Marek and Hahn published over 70 years ago [192]. Since that time, for many years interest in this molecule was rather occasional. But starting from the 1980s N20 has been a subject of ever-increasing attention of researchers because of two factors. The first is an ecological concern and a necessity of abating N20 emissions. Numerous works in this field are discussed in several reviews [185-187] and are not considered in this chapter. 

It could also be recovered as nitrous oxide for sale, but this has not been economically attractive. The major adipic acid producers, worldwide, have agreed to implement N2O abatement measures using one or the other of these options by 1998. Feasibility studies of a possible longer range solution have been conducted of an alternate enzymatic route that converts glucose to muconic acid, which could then be catalytically reduced to adipic acid, but this has not as yet been proven on a commercial scale (Eq. 19.74 [35]). 

Different options are available for the abatement of nitrous oxide (i) N2O decomposition in boilers (thermal destruction, efficiency higher than 98%), (ii) conversion of N2O into recoverable NO and (iii) catalytic dissociation of N2O to N2 and O2 (efficiency higher than 90-95%) [9]. 

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