Sustainable production of high-energy-density jet fuel via cycloaddition reactions

Developing an energy supply-chain based on renewable biomass holds great potential to build a low carbon society.High-energy-density(HED)jet fuel,featuring unique fused/strained cycloalkanes,is of great significance for volume-limited military aircrafts,as their high density and combustion heat can extend flight duration and increase the payload.Therefore,the exploration of biomass-based routes towards HED fuel has drawn much attention over the past decade.Cycloaddition reaction features rapid construction of various carbocycles in an atom-and step-economical fashion.This elegant strategy has been widely applied in the manufacture of sustainable HED fuel.Here we carefully summarize the progress achieved in this fascinating area and the review is categorized by the cycloaddition patterns including[4+2],[2+2],[4+4],and[2+1]cycloadditions.Besides,the energy densities of the as-prepared biofuels and petroleumbased fuels(conventional Jet-A and advanced JP-10)are also compared.This review will provide important insights into rational design of new HED fuel with different ring-types/sizes and inspire the chemists to turn those literature studies into practical applications in military field.

Functional groups evolution during GBW110031 anthracite combustion based on molecular models construction

Fourier transform infrared spectroscopy(FTIR)and Carbon-13 nuclear magnetic resonance(^(13)C NMR)techniques were applied to establish the molecular models of anthracite combusted at 490℃ and 690℃(490-C and 690-C).The evolution laws of functional groups were investigated based on the constructed models and quantitative changes calculated by FTIR results.The content of aromatic groups kept decreasing before 500℃;-CH_(3)/-CH_(2)-showed a rising trend during combustion;and the content of oxygen functional groups kept declining before 400℃.The chemical formulas of 490-C and 690-C were C_(217)H_(106)O_(12)N_(2)S_(2) and C_(201)H_(59)O_(8)N_(3)S_(2),respectively.690-C model was more compact than that of original anthracite and 490-C due to the spilt of carbon skeleton and the shedding of aliphatic chains during combustion.Total sulfur content in anthracite showed a sudden rise at 690℃ which could be attributed to the generation of organic thiophene;one more pyrrole in 690-C model resulted from the conversion of pyridine at such high temperature.