A method of producing DEMN eutectic comprises reacting a reactant mixture comprising ethylenediamine and diethylenetriamine with aqueous nitric acid to form a reaction mixture comprising diethylentriamine trinitrate and ethylenediamine dinitrate. The reaction mixture is combined with methylnitroguanidine and nitroguanidine to form an aqueous slurry. Water is removed from the aqueous slurry. A method of producing an energetic composition, and a system for producing DEMN eutectic are also described.