Gas-phase nitration of paraffins - with nitrogen dioxide in presence of chlorine for higher conversion

摘要

The parent patent describes the prepn. of nitroparaffins by gaseous-phase nitration of a hydrocarbon (e.g. propane or butane) with pure NO2 at 180-320 degrees C. In this addition, the reaction is effected in the presence of Cl2 (pref. present as 1-5 vol. % of the reaction mixt.) and ot. O2. Overall conversion of NO2 into nitroparaffins is increased (e.g. from 28% to 48% with propane). The product distribution is modified; with propane the ratio of (-nitro to 2-nitro product is increased, typically from 0.63 to 1.6. Reaction is esp. at 280-320 degrees C for 3-5 mins.; the conversion passes through a maximum. Prefd. reaction mixt. compsn. (vol. %) is 5-20 NO2, 75-90 propane, opt. 5-15 oxygen, and 1-5 (based on total of other reactants) of Cl2. Small amts. of chlorinated products are also formed.