Exothermic nitrations

Since mixing of glycol and MA was very thorough and rapid this AT mirrors the progress of the exothermic nitration reaction. Note the strong influence of mixed acid water content on the nitration rate. This agrees with Oehman et al (Ref 56a), except that Roth et al observed... 

Note The exothermic nitration of phthalic acid or phthalic anhydride by a fuming nitric acid-sulfuric acid mixt may give mixts of the potentially expl phthaloyl nitrates or nitrites or their nitro derivatives. Formation of these compds can be avoided if the nitrating mixt is... 

Investigation, analysis and optimization of exothermic nitrations in microreactor processes, in Matlosz, M., Ehrfeld, W., Baselt, j. P. (Eds.), Microreaction Technology - IMRET 5 Proc. of the 5th International Conference on Microreaction Technology, pp. 446 54, Springer-Verlag, Berlin (2001). 

The dangerously exothermic nitration of the aldehyde with cone, nitric acid is adequately controlled on a several hundred g scale by an automated assembly of laboratory apparatus. 

Use of medium-scale heat flow calorimeter for separate measurement of reaction heat removed via reaction vessel walls and via reflux condenser system, under fully realistic processing conditions, with data processing of the results is reported [2], More details are given elsewhere [3], A new computer controlled reaction calorimeter is described which has been developed for the laboratory study of all process aspects on 0.5-2 1 scale. It provides precise data on reaction kinetics, thermochemistry, and heat transfer. Its features are exemplified by a study of the (exothermic) nitration of benzaldehyde [4], A more recent review of reaction safety calorimetry gives some comment on possibly deceptive results. [5],... 

The main feature of a continuous process is that the final expl product does not remain in the app for a prolonged period of time and the quantiry accumulated at any period of time is much smaller than that in the batch process. The large quantity of expl material accumulated in a batch process, especially at the end of exothermic nitration,presents a serious safety hazard which is more or less absent in current continuous processes... 

Nitrobenzene is produced commercially by the exothermic nitration of benzene with fuming nitric acid in the presence of a sulfuric acid catalyst at 50 to 65 °C. The crude nitrobenzene is passed through washer-separators to remove residual acid and is then distilled to remove benzene and water. 

Strongly exothermic nitrations, polymerization of propylene, styrene butadiene. 1.2-3 MJ/kg (nitration, -130 MJ/kmol amination -120 MJ/kmol sulfonation or neutralization with sulfuric acid,... 

Loebbecke, S., Lutz, N., Tuercke, T., and Schweikert, W. (2003) Analysis and improvement of strong exothermic nitrations in microreactors. Chem. Eng. Res. 

Nitration of toluene is another exothermic nitration performed in 150 pm bore PTFE tube for varying acid strengths, reactor temperatures, and flow ratios [84]. Here too a strong influence of flow velocity on transformation rates of toluene nitration was observed ... 

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