In this paper, with 1000 kg of oil shale for research, the heat and material balance of Myanmar oil shale processing by Sanjiang gas combustion rectangular retort (SJ-retort) was calculated. The results show that the heat requirement of Myanmar oil shale retorting can be satisfied by its high-calorie retorting gas combustion as well as the heat release from the retorting process. In the study, 33.26% surplus retorting gas is obtained, which indicates that the Myanmar oil shale processing by SJ-retort is theoretically feasible. In addition, a concise and accurate method is proposed to calculate the gas balance of the retorting process, which can calculate the dynamic equilibrium value of various types of gases (total input and output gases, recycle gases, and the new air that enters the retort) when the retorting system reaches a steady state. This method was validated with the successful operation of a pilot-scale test for oil shale retorting in Shenmu of Shanxi province and Yaojie of Gansu province in China.

The reaction involving radical species is a key factor during the pyrolysis process used to form hydrocarbons. In this study, electron paramagnetic resonance (EPR) spectroscopy was used to characterize the properties of free radicals in the pyrolysates of oil shale. Effects of temperature on the yields and the EPR properties of thermal bitumen, shale oil, and semicoke were investigated, with the aim to understand the behavior of free radicals during the oil shale pyrolysis process. This study shows that the free radical concentrations (Ng) of shale oil and semicoke become higher with increasing temperature. The yield and Ng of thermal bitumen as an intermediate product follow the similar trends in the whole temperature range, first increasing and then decreasing. This is attributed to the competing mechnism of thermal bitumen generation and decomposition. The Ng of shale oil is lower than those of semicoke and thermal bitumen due to the coupling reaction of free radicals before the volatiles being condensed. The g-values and linewidths of thermal bitumen, shale oil, and semicoke are also affected by temperature, revealing the changing chemical structure and the surrounding environment of free radicals during the pyrolysis process.

•Five stable structures of cation–anion pair for chloroaluminate IL were obtained.•Multiple H-bonds were characterized between the ion pairs.•The average dispersion energy accounts for 10% of total interaction energy.•The interaction is co-determined by H-bond and Van der Waals interaction.The structures and interactions between cation and anion of triethylammonium chloroaluminate ([TEA]+[Al2Cl7]−) IL were systematically studied using density functional theory. Five stable conformers of ion pairs were obtained. Multiple H-bonds between cation and anion were characterized by geometry, vibrational frequency and interaction energy analysis. The order of interaction energy was obtained. Conformers containing N–H⋯Cl have relatively large interaction energy comparing to the rest of others. Dispersion energy accounts for over 10% of interaction energy for all conformers of interest. Natural bond orbital (NBO) analysis, atoms in molecules (AIM) theory and reduced density gradient (RDG) approach were employed to make a thorough study on the nature of interactions. It is found that medium H-bond interaction, weak H-bond interaction and Van der Waals interaction act together as the determining factor in the cation–anion interactions of [TEA]+[Al2Cl7]− ion pairs.

The pyrolysis experiments on Buton oil sand, Indonesia, were carried out using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) at different heating rates of 15, 20, 25, and 30 °C min−1. The kinetic parameters (apparent activation energy E and frequency factor A) of oil sand pyrolysis were determined using the Friedman procedure. It is found that the apparent activation energy E ranges from 13 to 85 kJ mol−1, corresponding to the conversion of 10−90%. The values of activation energy increase gradually with the increasing conversion. At the higher heating rate, the pyrolysis reaction is performed at the higher temperature region. In addition, it is also shown that the plot of ln A versus E for oil sand pyrolysis becomes a linear line.

Dihydroxy aromatics in coal tar undergo rapid coupling reactions with each other and with some coal-derived species during coal pyrolysis and liquefaction. However, only limited information on the structure of dihydroxy aromatics is known. In this study, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and gas chromatography−mass spectrometry (GC−MS) were used to characterize the dihydroxy aromatics in a low-temperature pyrolyzed coal tar and its distillate and residue fractions. Negative-ion electrospray ionization (ESI) FT-ICR MS spectra of coal-tar-derived samples had low molecular masses and narrow mass ranges. Negative-ion ESI is extremely selective for the dihydroxy aromatics present in coal tar. The O2 class species had the highest ion intensity among the species in the negative-ion FT-ICR mass spectrum for each sample. Dihydroxy compounds with an aromatic core structure of benzene, indan, biphenyl (and/or acenaphthene), and naphthalene were identified in the distillate fractions. Dihydroxy compounds in the residue fraction were dihydroxy fluorenes and phenanthrenes (and/or anthracenes). The O2 class species with relatively high molecular masses were likely dihydroxy acenaphthylenes and/or hydroxy dibenzofurans but could not be distinguished from each other because these compounds have the same molecular mass.

In this paper, the pyrolysis and extraction experiments on Buton oil sand bitumen were carried out. The contents of oil, water, gas, and semi-coke were determined and the pyrolysates were evaluated. The averaged oil content of Buton oil sand is about 20%. As measured by Dean–Stark toluene extraction, oil sand bitumen from Buton has the averaged bitumen content of about 30%. Three kinds of solvents were used to evaluate the bitumen recovery. The optimum conditions of solvent extraction were determined. The pyrolysates and bitumen were analyzed. The pyrolysis kinetics of oil sand were performed using the differential scanning calorimetry (DSC) at different heating rates of 15, 20, 25 and 30 °C/min. The kinetic parameters (apparent activation energy E and frequency factor A) of oil sand pyrolysis were determined using Coats–Redfern method. The value of apparent activation energy E was about 20 kJ·mol− 1, corresponding to the conversion of 5–35%. The apparent activation energy was nearly 40 kJ·mol− 1 while the conversion ranges from 40% to 95%.Highlights► A new solvent was used in experiment of oil sand extraction. ► The yield of extraction is close to the experiment using toluene. ► The Coats-Redfern model was used to calculate kinetics in oil sand and parameters were obtained. ► A lot of basic properties were analyzed. ► The basic data can provide theoretical basis for developing process of oil sands.