CALCULATION OF PHASE EQUILIBRIUM OF SYSTEM VAPOR–LIQUID IN TERNARY MIXTURES ISOAMYLOL–ETHANOL–WATER AND ISOBUTANOL–ETHANOL–WATER AT HIGH CONCENTRATIONS OF HIGHER ALCOHOLS

Проведено сравнение экспериментальных и расчетных данных при описании фазового равновесия по методам группового вклада UNIQUAC и NRTL для трехкомпонентных смесей изоамилол–этанол–вода и изобутанол–этанол–вода системы пар–жидкость при атмосферном давлении и высоких концентрациях высших спиртов (10–20% мас.). При расчете упругости паров чистых компонентов использовано уравнение Антуана. Приведены константы Антуана и парные энергетические параметры бинарного взаимодействия исследованных компонентов методов UNIQUAC и NRTL. Оба метода хорошо описывают равновесие в этих системах. The experimental and calculated data are compared in the description of phase equilibrium by the methods of the group contribution of UNIQUAC and NRTL for three-component isoamylol-ethanol-water and isobutanol-ethanol-water mixtures of the vapor-liquid system at atmospheric pressure and high concentrations of higher alcohols (10-20% by weight). The Antoine equation was used for calculation of the elasticity of vapors of pure components. The Antoine constants and the pairwise energy parameters of the binary interaction of the investigated components of the UNIQUAC and NRTL methods are given. Both methods well describe balance in these systems.

Effect of face-layer moisture content and face–core–face ratio of mats on the temperature and vapor pressure behavior during hot-pressing of wood-based panel manufacturing

Wood-based panels are made by consolidating mats of resinous wooden raw materials under a hot-pressing process. This study investigates the effect of face-layer moisture content (MC) and face–core–face (FCF) ratio of mats on the temperature and vapor pressure behavior during the hot-pressing process. Raising the face-layer MC and lowering the face-layer thickness was expected to reduce the time of reaching 100 °C in the hot-pressing process. When the temperature rise was limited or the core temperature decreased after reaching 100 °C (defined as plateau in this study), the mats with 25% and 30% face-layer MC with 1:2:1 FCF ratio reached the highest plateau core temperature, but required a longer time to complete the plateau. The relationship between core plateau temperature and maximum core vapor pressure was well described by the Antoine equation, which empirically models the vapor pressure as a function of temperature. The Antoine equation held across both face-layer MC series (varying face-layer MC at constant FCF ratio) and FCF series (varying FCF ratio at constant face-layer MC). The mat with 20% face-layer MC and 1:2:1 FCF ratio reached 180 °C within the shortest time, regardless of the evaluation conditions.

Determination of Natural Loss of Gasoline and Diesel Fuel during the Tank Storage

In this work, we studied the processes of evaporation of gasoline and diesel fuel during their storage. We assessed of the temperature dependence of the content of hydrocarbon vapors in the gas phase over petroleum products. It was found that the experimental data are best described by the empirical equation based on the Antoine equation. An algorithm is proposed for calculating the natural loss of gasoline and diesel fuel, as well as approaches to its reduction.

Bio-Based Solvents and Gasoline Components from Renewable 2,3-Butanediol and 1,2-Propanediol: Synthesis and Characterization

In this study approaches for chemical conversions of the renewable compounds 1,2-propanediol (1,2-PD) and 2,3-butanediol (2,3-BD) that yield the corresponding cyclic ketals and glycol ethers have been investigated experimentally. The characterization of the obtained products as potential green solvents and gasoline components is discussed. Cyclic ketals have been obtained by the direct reaction of the diols with lower aliphatic ketones (1,2-PD + acetone → 2,2,4-trimethyl-1,3-dioxolane (TMD) and 2,3-BD + butanone-2 → 2-ethyl-2,4,5-trimethyl-1,3-dioxolane (ETMD)), for which the ΔH0r, ΔS0r and ΔG0r values have been estimated experimentally. The monoethers of diols could be obtained through either hydrogenolysis of the pure ketals or from the ketone and the diol via reductive alkylation. In the both reactions, the cyclic ketals (TMD and ETMD) have been hydrogenated in nearly quantitative yields to the corresponding isopropoxypropanols (IPP) and 3-sec-butoxy-2-butanol (SBB) under mild conditions (T = 120–140 °C, p(H2) = 40 bar) with high selectivity (>93%). Four products (TMD, ETMD, IPP and SBB) have been characterized as far as their physical properties are concerned (density, melting/boiling points, viscosity, calorific value, evaporation rate, Antoine equation coefficients), as well as their solvent ones (Kamlet-Taft solvatochromic parameters, miscibility, and polymer solubilization). In the investigation of gasoline blending properties, TMD, ETMD, IPP and SBB have shown remarkable antiknock performance with blending antiknock indices of 95.2, 92.7, 99.2 and 99.7 points, respectively.

Synthesis and Characterization of New Solketal Alkylesters Usable as Diesel Biobased Fuel Additives

There are described experimental studies on the esterification of solketal, (the cyclic acetal produced from glycerol and acetone reaction), by transesterification reactions of the -OH group with methyl esters of C3 -C10aliphatic acids (propionic, pentanoic, hexanoic, octanoic and decanoic). The goal was to obtain better additives for diesel and biodiesel fuels, as compared to solketal. The measured physical properties (especially density, viscosity and water solubility) of the synthesized solketal esters, closer to the corresponding ones for the diesel and biodiesel fuels, permit to suppose that these new compounds should be better additives for diesel type fuels, as compared with solketal. For three of these esters there were studied the liquid-vapor equilibrium at different temperatures, determining also the Antoine equation coefficients for the calculation of vapor pressure.