Parameters affecting mechanochemical nitration of aromatic precursors

Document Type

Article

Publication Date

12-31-2021

Abstract

Using MoO3 as catalyst and NaNO3 as nitronium source, aromatic precursors were nitrated in a planetary ball mill. Reaction times and nitrate/precursor molar ratios varied in the experiments. Nitration was observed with maximum yields approaching 80%. Product ratios of para to ortho isomers were consistently above 1, indicating reaction on the catalyst surface. Byproducts, including oxidation products and double nitration products, were observed. The product yield approached its theoretical maximum when the aromatic precursor was the limiting reactant; the yields remained well below their expected maxima when the limiting reactant was nitrate. Thus, the catalyst sites necessary to generate nitronium may be blocked by the excess of the aromatic precursor in such cases. Correlation of the reaction rates with characteristics of the precursors suggests the importance of both physical and chemical parameters. Factors affecting the reaction rate include the aromatic activation, basicity, enthalpy of vaporization, reaction enthalpies and viscosity.

Identifier

85109445400 (Scopus)

Publication Title

Chemical Engineering Science

External Full Text Location

https://doi.org/10.1016/j.ces.2021.116906

ISSN

00092509

Volume

246

Grant

W912HQ19P0007

Fund Ref

Army Research Laboratory

This document is currently not available here.

Share

COinS