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A methodological approach towards synergistic effects from co-pyrolysis of lignocellulosic biomass with low-rank coal was proposed. The main maceral group from low-rank coal and primary organic components from biomass were selected to investigate the interaction of organic components. Thermal behavior and kinetic analysis on the co-pyrolysis of cellulose with acid-washed low-rank coal/vitrinite/inertinite were explored via TGA combined with iso-conversional method. The results indicated that the maceral group from low-rank coal showed different synergistic effects on the pyrolysis parameters and product distribution. The synergistic effect of vitrinite on the yield of volatile was closely related to its mass ratio. Positive and negative synergistic effects were observed when the mass ratio of vitrinite was 25% and 75%, respectively. Inertinite inhibited the formation of volatiles during co-pyrolysis and overall exhibited a negative synergy. No obvious synergy was observed for acid-washed low-rank coal when the heating was 10 °C·min−1 and 20 °C·min−1, while positive synergistic effects were found at a high mass ratio and heating rate. The integrative action of maceral groups played a significant role during the co-pyrolysis process.

CO2 dry reforming of methane (DRM) is one of the most promising routes for the large-scale utilization of greenhouse gases (CO2 and CH4). However, it is still of challenges to develop catalysts that are efficient and cheap but are of high resistivity in coke formation to maintain long-term stability. Herein, K2CO3 was used as a promoter to enable dynamic coke elimination reaction over the Ni/Al2O3 for CO2 reforming of CH4. K2CO3-modified Ni/Al2O3 catalysts were synthesized via a wet co-impregnation method and investigated for DRM. The 1.0 K-Ni/Al2O3 exhibited the best stability in the test of 96 h on stream at 800 °C. It was found that coke resistance of K2CO3 modified catalyst was significantly improved, as the coke formation on 1.0 K-Ni/Al2O3 catalyst was only 1/3 of that on Ni/Al2O3 catalyst after a long-term test. Characterization results showed that the growth of Ni particles was suppressed because the addition of K2CO3 enhanced the interaction between Ni and Al2O3. Meanwhile, the addition of K2CO3 raises the basicity of the catalysts, which enhances the adsorption of CO2 on the surface and subsequently facilitates CO2 dry reforming of CH4. In addition, the transient experiment reveals that K2CO3 enables a dynamic coke elimination reaction (KCER) via enhancing the catalytic reaction of disordered carbon with CO2, which is considered as a promising low-cost approach to stabilize the performance of the Ni-based catalysts in DRM reaction.

A new strategy of using graphene to modify porous organic solid acid catalyst for alkylation desulfurization is proposed by taking advantage of the π-π interaction between graphene and thiophenic sulfur. A graphene-modified sulfonated porous organic polymer (POP) supported phosphotungstic acid (HPW) catalyst (HPW/POP-G-SO3H) is successfully prepared by the solution polymerization-sulfonation-impregnation method. Steam adsorption experiment results show that graphene modification could increase the adsorption capacity of 3- methylthiophene (3-MT), but has little effect on the adsorption of isopentane; therefore, the selective adsorption of 3-MT could be enhanced. DFT calculations plus dispersion corrections also show that the adsorption energy of 3-MT on graphene is higher than that of isopentene on graphene and higher than those of 3-MT and isopentene on sulfonated POP. Subsequently, the catalytic activity test of alkylation desulfurization confirms that graphene-modified supported HPW catalyst shows higher alkylation desulfurization activity. This could support our assumptions. After recycles of 6 times, the 3-MT conversion on HPW/POP-G-SO3H catalyst decreases slightly, which possesses good recycling performance. Therefore, HPW/POP-G-SO3H catalyst will have broad application prospects in the field of alkylation desulfurization.

From the perspective of intensifying the pyrolysis process, suspension pyrolysis characteristics of ultra-fine low-rank coal via conveyor bed (1500 kg/h) were studied. The effects of coal particle size, pyrolysis temperature, and heating rates on the distribution of products were investigated. The relationship between the pyrolysis process and product quality, such as gas, tar, and char, was analyzed. The results showed that suspension pyrolysis enhanced the heat and mass transfer of the upgrading process. When the pyrolysis temperature was between 550 and 650 °C and coal particle size in the range of 0.075 ~ 0.105 mm, the yield of tar reached about 145% of the Gray-King tar yield. The analysis of group composition and four main components of tar showed that each fraction contained a certain amount of chain hydrocarbons or saturated hydrocarbons, which were mainly aromatic hydrocarbon compounds. The effective gas content from pyrolysis was H2 (19.32 vol%), CH4 (17.59 vol%), CO (12.53 vol%), and the low calorific value was about 900 kcal/Nm3. With the increase of pyrolysis temperature, the overall yield of pyrolysis gas increased, and the yields of H2 and CH4 increased linearly with temperature. The mass fraction of volatiles in char was less than 8%, while the mass content of fixed carbon was more than 80%. With the increase of pyrolysis temperature, the fixed carbon and ash content of the char increased, but the volatile matter decreased. This study provides a fundamental basis for the improvement of the pulverized coal pyrolysis process on large-scale installation.

An eight-lump kinetic model contained 21 kinetic parameters was proposed to describe the secondary reaction process of fluid catalytic cracking (FCC) gasoline. The model was solved by hybrid particle-swarm optimization (HPSO) which incorporated evolutionary strategies and the simulated annealing method into particle swarm optimization (PSO). A series of experiments were carried out in a riser reactor over an improved Y zeolite catalyst with different temperatures, catalyst to oil ratios and vapor residence times. The product distribution was obtained to estimate the 21 kinetic parameters of model; the calculated results obtained using the HPSO algorithm agreed well with the experimental results.

To predict the viscosity of any given biodiesel fuel (FAME mixture), a novel topological index based on the distance matrix and adjacent matrix of the molecular structure is proposed. The new topological index can reflect the information of the molecular structure for fatty acid methyl ester (FAME), such as the size of molecular, unsaturated bond and branch degree. Combined with the modified Grunberg–Nissan or Hind equation, the topological index values of the FAME mixture were calculated. Then, relates the topological index values of the FAME mixtures with the viscosities of them, two linear regression equations were obtained. Using these regression equations, the viscosity of biodiesel fuels were predicted. The results show the modified Grunberg–Nissan equation with a higher precision of prediction than the Hind equation regression equation.