Catalytic production and application of bio-renewable butyl butyrate as jet fuel blend- A review

Butyl butyrate (BB) derived from bio-renewable resources is the most promising jet fuel blend. This review highlights essential properties of jet fuel, including calorific value, kinematic viscosity, freezing point, flash point, auto-ignition temperature, and density to compare with different bio-renewable chemicals, which are compatible to be blended with the jet fuel. A detailed discussion follows on the importance of intermediate formation, reaction mechanism, and catalyst properties that are critical towards the production of bio-renewable resource-derived BB. BB is primarily produced via the esterification of butyric acid (BA) in butanol (BuOH) with or without using a catalyst. The corresponding reactions are carried out in both homogeneous and heterogeneous phases, provided it has acidic properties. Thus, a wide range of acidic catalysts such as [HSO₃-pmim] HSO₄ ionic liquids, heteropolyacid, methanesulfonic acid, Dowex 50 Wx8-400 resins, and sulfonated char causes up to 98%, 97.9%, 93.2%, 95.3%, and 90% of BB yield, respectively are critically reviewed. Moreover, reaction mechanism, product, and by-product formation that primarily dictate the BB yield and selectivity have been comprehensively reviewed. In addition, catalytic and mechanistic insights on BB production from other bio-renewable resources such as butyric anhydride, butyraldehyde, dibutyl ether, and methanol have been discussed in this review.

Structure-composition relationships in ternary solvents containing methylbenzoate

Thermophysical properties of the hexane+1-chlorohexane (or hexanoic acid or diisopropylether)+methylbenzoate ternary systems and their binary constituents are reported at 298.15 K and 0.1 MPa over the whole composition range. The properties and the optimized geometry of the gas-phase components were appraised from the density functional theory. To find out the causal link between the thermophysical measurements and the molecular level features, the derived mixing and excess functions of the ternary systems were looked into according to the scaled particle and Kirkwood-Buff analyses. The hydrogen bonding and dipole interactions along with the geometry effects brought about by the very different size and shape of the components give rise to complex mixed structures. Application of semiempirical models and use of simple cubic equations of state combined with a one-parameter van der Waals mixing rule has led to prediction of the ternary properties with variable degree of precision.

Properties of 1,8-Cineole: A Thermophysical and Theoretical Study

This paper reports on an experimental and theoretical study of 1,8-cineole, one of the main components of essential oils in different plants. The pressure-volume-temperature behavior of this fluid was evaluated accurately over wide temperature and pressure ranges and correlated successfully with the empirical TRIDEN equation. From the measured data, the relevant derived coefficients isothermal compressibility, isobaric expansibility, and internal pressure were calculated. The isobaric heat capacities at high pressure were extrapolated from the data measured at atmospheric pressure. The cubic equations of state by Soave, Peng-Robinson, Stryjek-Vera modification of Peng-Robinson, Patel-Teja, Sako-Wu-Prausnitz, and the SAFT and PC-SAFT molecularly based equations of state were used to predict the PVT behavior. The SAFT and PC-SAFT parameters for 1,8-cineole were obtained from correlation of available saturation literature data; the best results were provided by Sako-Wu-Prausnitz and PC-SAFT equations of state, whereas the classical ones were shown to be inadequate. The molecular structure was studied by quantum computations at the B3LYP/6-311++g(d) level and classical molecular dynamics simulations in the NPT ensemble with the OPLS-AA forcefield. On the basis of both macroscopic and microscopic studies, a complex fluid structure was inferred.