Physicochemical principles of the technology of modified pyrotechnic compositions to reduce the chemical pollution of the atmosphere

This paper presents the results of determination of conditions for the production of modified pyrotechnic compositions that allow initiating atmospheric precipitation, neutralizing their acidity and scavenging toxic substances from the atmosphere. Taking into account the requirements of environmental protection, the use of Mg as a fuel and KNO3 as an oxidizing agent in the pyrotechnic composition was suggested. The combustion of the proposed two-layer pyrocomposition impedes the release of chemically hazardous combustion products (NH3 and HCl). Using TERMO-CALC software package, the content of ammonia and hydrogen chloride in the combustion products of the proposed mixtures was determined at the best fuel-oxidizing agent ratio. The thermodynamic calculations were performed to determine the best reducing/oxidizing agent mass fraction ratio which was stated to be 1:8. The experimental study of the main parameters of high-temperature oxidation (temperature and burning rate) of pyrotechnic compositions was carried out. A two-layer structure of the explosive charge with a highly flammable primary layer is proposed, which substantially increases the probability of ignition of the pyrotechnic mixture triggered by an electric spark. In order to intensify a decrease of the acidity of atmospheric precipitation, a technology for modifying pyrotechnic compositions by adding KOH and cellulose was proposed. The modification of the developed composition with the use of NaOH allows effectively neutralizing such dangerous gases as chlorine and phosgene. The established physicochemical basics of the technology for modifying pyrotechnic compositions for complex purposes allow developing multi-functional explosive compositions aimed at artificial initiation of precipitation and chemical neutralization of hazardous substances in the atmosphere.