The high content of heteroatoms and trace metals makes it difficult to upgrade poor-quality oils (PQO). The copyrolysis or co-hydrogenation of coal tar (CT)/vacuum residue (VR) is a new approach for the efficient utilization of PQO. The products of CT/VR co-pyrolysis and co-hydrogenation were characterized by RV, TG-FTIR, and GC x GC-TOF. Co-pyrolysis reduces the reaction harshness by lowering the activation energy of pyrolysis. Copyrolysis changes the reaction paths of oxygen-containing free radicals by promoting the generation of oxygen-containing organic compounds and inhibiting coke generation by increasing the pyrolysis spillover of unsaturated hydrocarbons. Co-hydrogenation increased the gasoline and diesel yields while reducing coke production. The saturates, aromatics, resins, and asphaltenes of CT and VR experienced a significant increase in the gasoline and diesel fractions after hydrogenation. The gasoline and diesel content enhancement in the fourcomponent hydrogenation products of CT increased with increasing polarity, whereas the opposite trend was observed for the four-component hydrogenation of VR. There was a clear synergistic effect between the aromatics of CT and VR in terms of hydrogenation saturation, while the synergistic effect of the aromatics was somewhat weaker. The saturates and resins had an inhibitory effect on each other.

The high tolerance to feed oil makes slurry bed hydrocracking technology one of the main streams of research, but the relationship between hydrogenation and deactivation of slurry bed catalysts remains unclear. In this study, the distribution of vacuum residue (VR) hydrogenation products, coke generation, and catalyst deactivation patterns were analyzed using MoS2/TiO2 as the hydrogenation catalyst. With an increase in the reaction temperature or decrease in the hydrogen pressure, the cracking performance gradually improved, the hydrogenation saturation effect gradually weakened, and the oil-to-coke ratio (OCR) gradually decreased. This implies that the influence of the lightning effect from coke generation gradually increased. The conversion rate of VR to gasoline and diesel components is 3.8 times higher than the conversion rate to coke and gas. At lower temperatures, coke was dominated by graphitic carbon encapsulated on the catalyst surface. As the temperature increased, the content and lamellar diameter of graphitic carbon decreased, and the content of amorphous carbon increased. An increase in temperature also promoted the dealkylation reaction and coke condensation, resulting in a decrease in pyrolytic activity. VR hydrogenation was subjected to kinetic analysis, and a model for MoTi-5-catalyzed VR deactivation was developed using OCR to deduce the degree of contribution of coke generation to lightning.

Background Molybdenum disulfide is one of the main catalysts used in slurry-bed reactors. However, monolayer molybdenum disulfide with high hydrogenation activity is extremely difficult to obtain owing to the van der Waals forces between layers. Methods MoTi-X catalysts with different MoS2 loadings were synthesized using a hydrothermal method. Changes in the active phase of MoTi-X during hydrogenation were also analyzed by TEM, XPS, and Raman spectroscopy. Significant findings MoTi-X catalysts synthesized by a two-step hydrothermal process allowed for the simultaneous generation of monolayer MoS2 and hydrogenation. The results of the phenanthrene-phenol co-hydrogenation system showed that the different active sites on MoS2 were responsible for its Hydrogenation and Hydrodeoxygenation properties. Using MoTi-X to catalyze coal tar (CT) hydrogenation, the total content of gasoline and diesel fractions was increased by 11.3 %, which is 3.3 times more effective than industrial four-stage hydrogenation. The average molecular mass, viscosity, and density of the coal tar were reduced by 35 %, 96 %, and 6 %, respectively. The application of MoTi-X catalysts for CT hydrogenation can fill the gap in the research on CT slurry-bed hydrogenation catalysts and improve the competitiveness of enterprises.

In this study, the homogeneous catalyst phosphotungstic acid (H3PW12O40, HWP) was immobilized on heterogeneous catalyst AlOOH spheres via an impregnation-calcination method to obtain AlOOH-H3PW12O40 (AlOOHHWP). HWP was successfully impregnated onto the AlOOH, and altered AlOOH's crystal structure, which increased the surface-OH groups and improved catalytic efficiency. Meanwhile, AlOOH stabilizes the molecular structure of HWP. The AlOOH-HWP was used in the catalytic ozonation of coal chemical wastewater, which was 21.79 % higher than that of ozone alone. Through single-factor experiments, the effects of pH, ozone concentration, and catalyst bed height on COD removal and ozone utilization rate were investigated. Response surface methodology (RSM) was employed to optimize experimental conditions, resulting in the highest removal rate of COD (88.83 %) at a pH of 6.27, an ozone concentration of 120 mg/L, and a catalyst bed height of 8.86 mm. After five cycles of use, AlOOH-HWP still exhibited excellent catalytic activity. Electron paramagnetic resonance (EPR) confirmed that the AlOOH-HWP facilitates the decomposition of ozone into hydroxyl radical (center dot OH) and singlet oxygen (1O2), while no radical signals are detected in the single ozone system. The radical quenching experiments found that center dot OH played a more significant role in removing COD. FTIR, UV-Vis, 3D-EEM, and GC-MS analysis revealed significant changes in the types of pollutants in coal chemical wastewater after catalytic ozonation. This study confirmed the potential of AlOOH-HWP for catalytic ozonation in wastewater treatment.

A new coupling process for highly efficient extracting phenols from coal tar and capturing carbon dioxide in exhaust gas employing aqueous amine was developed, which improved the shortcomings of high cost and environment pollution of single industrial process by process coupling and strengthening. The cyclic experiment of this process with monoethanolamine solution as extractant reached a stable state after 4 cycles. Under the steady-state, the total extraction yield of phenols and the total recovery yield of monoethanolamine and water were 100%, 98.8% and 90.9%, respectively. In addition, the empirical and semi-empirical models based on the experimental and literature data were constructed, and the models were linked to Aspen Plus software to simulate and optimize the coupling process. The optimization results showed that the unit production cost of present green process was 274.79 CNY.t(-1), which only 25.4% and 65.6% of the cost for the traditional and improved industrial processes, respectively. Especially, the consumption of mineral resources and pollutant emissions in this process were reduced compared to the industrial processes. This work provides an industrially promising method for extracting phenolic compounds from coal tar and synergistically capturing carbon dioxide in industrial exhaust gas, and lays an engineering foundation.

In the work, bismuth tungstate (Bi2WO6, orthorhombic system) photocatalyst nanomaterial was synthesized by hydrothermal method. The photocatalytic ozonation oxidation synergistic degradation on organic pollutants in coal chemical phenol-ammonia wastewater by Bi2WO6 was studied. The effects of ozone (O3) concentration, catalyst dosage, pH and O3 flow rate on the degradation efficiency of wastewater were investigated, respectively. The study found that the degradation processes of these four single factors were fitted kinetically and aligned with the pseudo second order kinetics model, and the maximum chemical oxygen demand (COD) removal rate of the coal chemical phenol-ammonia wastewater was 56.34 ∙ O_2^- , which results in the degradation on organic pollutants in coal chemical phenol-ammonia wastewater. The analysis of water quality and GC–MS indicated that most pollutants present in coal chemical phenol-ammonia wastewater had degraded upon treatment. Furthermore, the BOD/COD ratio of coal chemical phenol-ammonia wastewater was increased from 0.25 to 0.32. Moreover, the COD removal rate only decreased to 70.25

Co-hydrogenation of coking residual (CR) and coal tar (CT) is an important idea to expand the field of petroleum processing technology. A low crystallinity molybdenum disulfide catalyst was synthesized by the two-step hydrothermal method and applied to CT/CR co-hydrogenation. The co-hydrogenation can increase the yield of light fuel while decreasing gas, and coke yields. In addition, the co-hydrogenation will result in a significant increase of polycyclic aromatic hydrocarbons (PAHs), a significant decrease of alkanes and monocyclic aromatic hydrocarbons (MAH), and a favorable naphthalene generation in the products. This provides a new idea to produce chemicals from poor-quality oils.

Loaded Mo-based nano hydrogenation catalysts were synthesized by a two-step hydrothermal method using highly dispersed TiO2 nanoparticles as carriers. During the hydrogenation of coal tar (H2 and S), the catalysts exhibited a gradual transition from Mo0+ and Mo6+ to highly water-soluble Mo4+, while a large number of monolayered molybdenum disulfide configurations with high hydrotreating activity appeared. MoS2/TiO2 synthesized by a two-step process increased the total content of gasoline and diesel in coal tar from 45.4 % to 54.8 %, and the hydrogenation effect was much higher than that of unloaded MoS2. In addition, the MoS2-T and MoS2/TiO2 catalysts showed significant effects in increasing H/C, decreasing average molecular mass, decreasing asphaltene content, and decreasing trace metal iron content. However, the MoS2/TiO2 catalysts were much better than MoS2-T catalysts, which was attributed to its monolayer MoS2 properties that gave it higher catalytic performance for hydrotreating. It was also shown that the increase in total gasoline and diesel content after catalytic hydrotreating of coal tar was mainly at the expense of asphaltenes.

To improve the adsorption and reusability of polypropylene (PP) fiber membranes, the organically modified saponite (Sap@P(St-co-MMA)) was prepared by solution polymerization. Furthermore, PP-based nanocomposite fiber membranes with strong oil adsorption, thermal stability, and reusability were prepared via melt-blown technology. The increased specific surface area of PP-based nanocomposite fiber membranes (PP-1.5%) provided more active sites for the oil adsorption. Simultaneous rheology and Fourier transform infrared measurements tests showed that Sap@P(St-co-MMA) enhanced the crystallinity of PP matrix, promoted the regular arrangement of molecules, and improved the intermolecular interaction force, which was beneficial for the oil adsorption. The adsorption of PP-1.5% (1.5 wt% addition of Sap@P(St-co-MMA)) fiber membrane for xylene and kerosene reached a maximum of 15.84 and 22.84 g g-1, respectively. In the treatment of coal tar wastewater, the removal rate of oil can reach 62.9%, and the removal rate can still reach 51.17% after five cycles of experiments. In summary, PP-1.5% fiber membrane does not produce secondary pollution to the environment, and is a kind of oil removal material with good application prospect.Highlights PP-based nanocomposites fiber membrane with strong oil adsorption was prepared. Organically modified saponite had strong heterogenous nucleation for PP matrix. Sap@P(St-co-MMA) increased the specific surface area of PP-based fiber membrane. Schematic diagram of the preparation and application of polypropylene/organically modified saponite nanocomposites fiber membrane with strong oil-adsorption. image

With the growing demand for gasoline and diesel fueland the shortageof conventional oil reserves, there has been extensive interest inupgrading technologies for unconventional feedstocks such as heavyoil. Slurry bed reactors with high tolerance to heavy oil have beenextensively investigated. Among them, dispersive MoS2 isfavored for its excellent hydrogenation ability for heavy oil evenunder harsh reaction conditions such as high pressure and high temperature,its ability to effectively prevent damage to equipment from depositedcoke, and its ability to meet the requirement of high catalyst dispersionfor slurry bed reactors. This paper reviews the relationship betweenthe structure and hydrogenation effectiveness of dispersive molybdenumdisulfide, the hydrogenation mechanism, and the improvement of itshydrogenation performance by adding defects and compares the applicationof molybdenum disulfide in heavy oil hydrogenation, desulfurization,deoxygenation, and denitrification. It is found that the current researchon dispersive molybdenum disulfide catalysts focuses mostly on thereduction of stacking layers and catalytic performance, and thereis a lack of research on the lateral dimensions, microdomain regions,and defect sites of MoS2 catalysts. The relationship betweencatalyst structure and hydrogenation effect also lags far behind theapplication of MoS2 in the precipitation of hydrogen, etc.Oil-soluble and water-soluble MoS2 catalysts eventuallyneed to be converted to a solid sulfide state to have hydrogenationactivity. The conversion history of soluble catalysts to solid-typecatalysts and the key to their improved catalytic effectiveness remainunclear.

Abstract Organically modified saponite (Sap@P(St-co-MMA)) additives were prepared by solution polymerization with saponite as matrix and with styrene and methyl methacrylate as monomer, poly (propylene) (PP)/Sap@P(St-co-MMA) nanocomposites fiber membranes are prepared by melt-blown spinning. PP fiber membranes with improved hydrophobicity, thermal stability, crystallinity, and adsorption properties were prepared. The specific surface area of PP fiber membranes (PP-1.5%) with the addition of 1.5% additive is 129.11 m2 g− 1, which provided more active sites for the adsorption of oil substances from wastewater. Simultaneous rheological measurement and FTIR analysis showed that Sap@P(St-co-MMA) could improve the crystallinity of PP matrix, so that PP molecules were regularly arranged to improve the intermolecular interaction force, which was favorable for the adsorption of oil substances. The adsorption of PP-1.5% fiber membrane conformed to a pseudo-second order kinetic model, which could be expressed by the Langmuir isothermal model, and the oil removal of 51% was still achieved after 5 cycles of recycling with a maximum removal of 65%. Accordingly, PP-1.5% fiber membrane can efficiently remove the oil substances in wastewater without secondary pollution to the environment, and it is a kind of oil removal material with good application prospect.

Nucleating agents for polyoxymethylene(POM)at home and abroad were classified in this paper.The influences of inorganic nucleating agent like calcium carbonate,Talc,diatomaceous earth,organic nucleating agent like carbon nanotubes,polyamide,POM,metal nucleating agent like magnesium oxide,ultrafine Fe powder and Talc/elastomer composite nucleating agent on crystallization characteristics and mechanical properties of POM were summarized in detail.Some technical ideas for developing POM nucleating agents were suggested.

Nucleating agents for polyoxymethylene(POM)at home and abroad were classified in this paper.The influences of inorganic nucleating agent like calcium carbonate,Talc,diatomaceous earth,organic nucleating agent like carbon nanotubes,polyamide,POM,metal nucleating agent like magnesium oxide,ultrafine Fe powder and Talc/elastomer composite nucleating agent on crystallization characteristics and mechanical properties of POM were summarized in detail.Some technical ideas for developing POM nucleating agents were suggested.