Exploding Nitromethane in silico, in real time

TL;DR

This study uses reactive molecular dynamics to analyze nitromethane detonation mechanisms, revealing how oxygen and water influence reaction speed and safety, with implications for industrial applications.

Contribution

It introduces in silico real-time simulation of nitromethane detonation, highlighting the roles of oxygen and water in reaction kinetics and safety.

Findings

Polarity of NM drives initial exothermic reaction

Oxygen accelerates oxidation process

Water inhibits but does not prevent detonation

Abstract

Nitromethane (NM) is widely applied in chemical technology as a solvent for extraction, cleaning and chemical synthesis. NM was considered safe for a long time, until a railroad tanker car exploded in 1958. We investigate detonation kinetics and reaction mechanisms in a variety of systems consisting of NM, molecular oxygen and water vapor. State-of-the-art reactive molecular dynamics allows us to simulate reactions in time-domain, as they occur in real life. High polarity of the NM molecule is shown to play an important role, driving the first exothermic step of the reaction. Presence of oxygen is important for faster oxidation, whereas its optimal concentration is in agreement with the proposed reaction mechanism. Addition of water (50 mol%) inhibits detonation; however, water does not prevent detonation entirely. The reported results provide important insights for improving applications of NM and preserving safety of industrial processes.