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Nitrogen and sulfur co-doped porous carbon materials with excellent electrochemical performance were prepared using a one-step carbonization and activation method.

A hierarchical porous zeolite Y (HPZY) supported Ni–Co catalyst was prepared by pyrolyzing nickel tetracarbonyl and using modified deposition-precipitation to highly disperse Ni–Co nanoparticles onto HPZY. Hecaogou subbituminous coal was effectively ethanolyzed to obtain ethanol-soluble portion (ESPE) in a high yield (21.2%). Sequentially, ESPE was subjected to the deep hydroconversion (DHC) over prepared Ni10%-Co3%/HPZY at 150 °C under 4 MPa of initial hydrogen pressure for 24 h in n-heptane to produce deeply hydroconverted ethanol-soluble portion (ESPDHC). All the group components in ESPE, including arenes (53.3%), oxygen-containing organic compounds (24.4%), and nitrogen-containing aromatics (2.3%) were completely converted to chain alkanes (CAs, 36.8%), cyclanes (39.2%), and hydroarenes (24.0%). In addition, the hydroisomerization of CAs and hydroreforming of aromatic rings (ARs) in ESPDHC are predominant over Ni10%-Co3%/HPZY with more accessibility of active sites under mild conditions. Ni10%-Co3%/HPZY with suitable acidity and highly dispersed Ni–Co nanoparticles can effectively activate H2 to H⋯H and further heterogeneously split H⋯H to H+ and H−. H⋯H and H+ transfer plays crucial roles in the DHC of ESPE. Correspondingly, the related mechanisms are evidenced by the DHC of 2,2′-oxydinaphthalene (ODN) over Ni–Co/HPZY. Ni10%-Co3%/HPZY maintains high activity for the DHC of ODN under mild conditions after 4 recycles.

A template-free strategy was designed to prepare hierarchical porous carbons (HPCs) using fluid catalytic cracking oil modified a coal tar pitch (CTP). The resulting HPCs possess large specific surface areas, reasonable pore size distributions, and wrinkled structures, which could improve the overall electrochemical performance. They exhibit a specific capacitance value of 329 F g−1 at 0.5 A g−1 and still maintain 220 F g−1 at 20 A g−1, manifesting the remarkable rate capability. Additionally, the assembled symmetrical supercapacitor delivers a highest energy density of 23.6 Wh kg−1 at a power density of 500 W kg−1 and outstanding cycle stability of 92.8% capacitance retention after 10000 cycles. This work paves a new way to fabricate advanced carbon materials from low-cost CTP and provides a promising approach for value-added utilization of CTP.

A supported nickle catalyst was prepared by loading ca. 11% of nickel nanoparticles (NNPs) on mesoporous zeolite Y (MZY) and denoted as Ni11%/MZY. A straw was methanolyzed at 300 °C to obtain methanol-soluble portion as a straw-derived bio-oil (SDBO) in the yield of 19.3%. According to the analysis with a gas chromatograph/mass spectrometer, SDBO consists of arenes (7.8%), oxygen-containing organic compounds (82.8%), nitrogen-containing organic compounds (6.3%), and sulfur-containing organic compounds (3.1%). It was subjected to catalytic hydroconversion (CHC) over Ni11%/MZY in n-hexane under 5 MPa of initial hydrogen pressure (IHP) at 160 °C for 16 h. As a result, all the compounds in SDBO were converted to chain alkanes (60.1%) and cyclanes (39.9%). In Ni11%/MZY, uniformly dispersed NNPs and strong Lewis acid sites in the defective crystal texture of MYZ play crucial roles in hydrogenating aromatic rings and removing heteroatoms (HAs), respectively. Benzyloxybenzene (BOB) was used as a lignin-related model compound. The main product from the CHC of BOB over Ni11%/MZY in n-hexane under 5 MPa of IHP at 160 °C for 2 h is methylcyclohexane in the yield of 90.9%, indicating that both hydrogenation of benzene rings and deoxygenation significantly proceeded. After being recycled 4 times, Ni11%/MZY is still active for the CHC of BOB.

An extraction-column chromatography system was designed to enrich and purify condensed arenes (CAs) from a high-temperature coal tar (HTCT). Pyrene, fluoranthene, phenanthrene, anthracene, and naph...

Understanding the molecular composition of oxygen-containing aromatics (OCAs) in low-temperature coal tar (LTCT) is of great importance for separating value-added chemicals from LTCT and catalytica...

Hanglaiwan subbituminous coal (HSBC) was subjected to solvent extraction (SE) with an isometric carbon disulfide/acetone mixed solvent (IMCDSAMS) to obtain a residue (RSE). Thermal dissolution (TD)...

The occurrence forms of organic nitrogen in Xianfeng lignite (XL), Xiaolongtan lignite (XLT) and Shengli lignite (SL) as well as their extraction residues were characterized by X-ray photoelectron spectroscopy (XPS). The results show that the content distributions of organic nitrogen in the three extraction residues are different, but all are mainly dominated by pyrrolic nitrogen. The NaOH-catalyzed supercritical methanolysis of lignite extraction residues at 300°C was then investigated, which indicates that the yields of petroleum ether soluble portions from supercritical methanolysis of extraction residues derived from XL, XLT and SL are 46.0%, 43.8%, and 47.6%, respectively. The characterization of nitrogen-containing compounds (NCCs) in petroleum ether soluble portions by Fourier transform ion cyclotron resonance mass spectrometry (FTICR/MS) indicates that NCCs are mainly composed of N1, N1O1-N1O5, N2, N2O1-N2O4, N3O2 and N5O2-N5O4 class species. The molecular structural characteristics of NCCs were speculated according to the distributions of double bond equivalent values and carbon numbers, which shows that most of NCCs contain oxygen-functional groups like hydroxyl and carboxyl groups, and the nitrogen atoms are mainly present in aromatic structures (mainly 1–3 aromatic rings) in the forms of pyrrolic, pyridinic and amino groups. The cleavage of C-O bridged bonds in lignite is an important pathway for producing NCCs.

An effective deep eutectic solvent (DES) combined with column chromatography was designed for separating nitrogen-containing aromatics (NCAs) from the light portion (LP, which is petroleum-ether-ex...

We reports the preparation of hierarchical activated carbon (HAC) obtained by CO2 activation of coal gasification residue (CGR) produced from two-stage acid leaching (TSAL). The performance of HAC on removing methylene blue (MB) from aqueous solution was investigated. The obtained HAC was characterized by N2 adsorption-desorption isotherm, Fourier transform infrared spectroscopy (FTIRS), and scanning electron microscopy (SEM). The results show that HAC exhibits hierarchical pore structure with high BET surface area (SBET = 862.76 m2 g-1) and total volume (Vtotal = 0.684 cm3 g-1). SEM images indicated a hierarchical pore texture, and FTIRS results reveal the presence of abundant organic functional groups. Adsorption studies were carried out and experimental data were fitted to 4 non-linear isotherm models and 4 kinetic models. The adsorption experimental equilibrium data of MB onto HAC were best fitted to the Redlich-Peterson (R-P). The kinetic data show that the pseudo-first-order (PFO) model is more suitable at low MB concentration, while the advantages of the pseudo-second-order (PSO) model and the Elovich model are more obvious as the concentration increases. Furthermore, according to the thermodynamic parameters, the HAC-MB adsorption process is spontaneous and endothermic.

Low-temperature coal tar (LTCT) is a sticky liquid mixture produced mainly from coal pyrolysis, which contains various value-added chemicals (VACs). Liquid-liquid extraction is considered as one of the green and effective ways to explore the organic composition and separate the VACs from LTCT. Herein, petroleum ether, methanol, and carbon disulfide were used to extract arenols from a LTCT. As a result, the relative content and absolute content of arenols extracted from the LTCT are ca. 96.3% and 85.9%, respectively. Among them, p-cresol is predominant, accounting for 22.2%. The isolated contents of arenols are up to 84.6%. Moreover, a kilogram-scale operation was carried out under the same conditions, which offers a potential application in industrial production.

A biochar (BC)-supported non-noble metal catalyst CoMoSxOy@BC was prepared by in-situ co-pyrolysis and ex-situ sulfurization, and a two-step conversion (TSC) strategy, including H2-controlled catal...

Spent auricularia auricular substrate (SAAS) was oxidatively degraded with aqueous hydrogen peroxide (AHPO)/acetic anhydride (AAH) to produce carboxylic acids (CAs) under mild conditions. The results show that up to 53.6% of the organic matter in SAAS was converted to the soluble species (SSs). In total 122 CAs were detected in the SSs by the analysis with a gas chromatograph/mass spectrometer, which can be classified into 29 group components, mainly being aliphatic acids and along with small amount of aromatic acids. Among the aliphatic acids, normal alkanedioic acids are the most abundant. The detected aromatic acids include benzoic acids, phthalic acids, trimellitic acids, pyromellitic acids, and their derivatives. The synergistic oxidation and the released OH, CH3COO , and HOO induced by AHPO/AAH play crucial roles in oxidatively degrading SAAS.

Two attapulgite powder (AP)-supported nickel catalysts were prepared by thermally decomposing nickel tetracarbonyl onto AP in a laboratory (L-Ni/AP) and in a factory (F–Ni/AP). The Ni nanoparticles...

A novel and highly active zeolite Y/ZSM-5 composite zeolite (CZ)-supported nickel catalyst (Ni/CZ with 10% of Ni loading) was prepared by modified deposition–precipitation to uniformly disperse Ni ...