Controllable integration of metal nanoparticles (NPs) and metal–organic frameworks (MOFs) is of significant importance in many applications owing to their unique properties. In situ efficient synthesis of metal NPs with different structures into MOFs is a great challenge. Herein, we report the nanostructures of octahedron and flower Pt–Cu frame@HKUST-1, which is successfully synthesized under a microwave irradiation method in only 30 min. In this study, Pt–Cu alloys, serving as the self-template, are synthesized first, followed by the HKUST-1 shell growing in situ via the consumption of Cu0. As multifunctional catalysts, the core–shell structures exhibit excellent performance for the hydrogenation of 1-hexene. Notably, octahedron Pt–Cu frame@HKUST-1 displays high turnover number (TON) and turnover frequency (TOF) of 1004 and 2008 h–1, respectively. Thanks to the protective effect of HKUST-1, the octahedron Pt–Cu frame@HKUST-1 can be recycled for at least four runs without serious loss of activity and obvious aggregation of Pt–Cu alloys. Furthermore, the size-selective catalysis is also well-demonstrated by choosing 1-hexene, cis-cyclooctene, and styrene as substrates.

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Inferior coker gas oil (ICGO) derived from Venezuelan vacuum residue delayed coking is difficult to process using fluid catalytic cracking (FCC) or hydrocracking (HDC). The high content of nitrogen and condensed aromatics leads to major coking and readily deactivates the acid catalyst. In this work, a sequence of hydrotreating (HDT) and FCC processing is used to effectively convert ICGO to a high-value light oil product. The results show a higher overall conversion and a significant increase in the yield of gasoline compared to FCC processing. Molecular level characterization of the nitrogen compounds and condensed aromatics before and after HDT confirms that the nitrogen content and the 2+-ring aromatic content decreased, whereas the single-ring aromatics increased. The nitrogen compounds were mainly N1, N1O1, N1O2, and N1S1 class species in basic nitrogen and N1, N1O1, N1O2, N2, and N2O1 class species in non-basic nitrogen. Moreover, the double bond equivalent of these species shifted to lower values. The decrease in the nitrogen compounds with a high heteroatom content reduces coking on the FCC catalyst. Subsequently, FCC unit performance and conversion to light oil increased. Moreover, the decrease in the size of N1 class compounds and the ease of their cracking following HDT improved the performance of the FCC unit. Partial saturation of condensed aromatics following HDT also made it easier to crack these compounds.

Non-catalytic hydrogenation with a hydrogen donor is a beneficial way for effective conversion of asphaltene to distillate with minimal coke formation. In this work, detailed product distribution, which includes gas, light oil [initial boiling point (IBP)–350 °C], middle oil (350–540 °C), heavy oil (>540 °C), asphaltene, and coke, obtained from non-catalytic hydrogenation of asphaltene with tetralin as a hydrogen donor, was investigated in an autoclave. The effects of reaction conditions, including reaction time, reaction temperature, and hydrogen donor/asphaltene weight ratio, on asphaltene conversion, detailed product distribution, liquid product yield, and liquid product selectivity were studied. Results showed that through controlling the reaction condition, asphaltene conversion and total liquid yield reached 72.72 and 70.34 wt %, respectively, and produced only 2 wt % coke and 0.34 wt % gas. We then developed a seven-lump kinetic model, including an active hydrogen lump to describe the reaction behaviors of asphaltene hydroliquefaction. Activation energies ranged from 106.07 to 237.50 kJ mol–1. The activation energies of the main reaction that asphaltene decomposed and hydrogenated by active hydrogen to produce heavy oil and middle oil were 106.07 and 109.06 kJ mol–1, respectively, which were lower than those of thermal cracking. The activation energy of distillate formation from active hydrogen combined with macromolecule radicals was 143.78 kJ mol–1. The detailed product yield predicted by the developed seven-lump kinetic model exhibited good consistency with the experimental data.

The hydrogen-donating ability (HDA) of the narrow fractions of coker gas oil (CGO), fluid catalytic cracking slurry (FCCS), and furfural extract oil (FEO) was investigated in an autoclave reactor. Anthracene was selected as a hydrogen acceptor probe for accepting hydrogen released by the hydrogen donor. Proton nuclear magnetic resonance (1H NMR) was employed to identify different categories of hydrogen of the mixture. On the basis of the 1H NMR data, a method for calculating the HDA was developed to characterize the hydrogen-donating properties of selected industrial distillate narrow fractions (IDNFs). The reliability of the proposed method was verified by the average molecular structure and hydrocarbon composition of narrow fractions. The HDA of the narrow fractions follows the order of FEO > FCCS > CGO, and that of the key components of IDNFs is FEO-5 > FCCS-6 > CGO-4. FEO-5 is the optimal candidate for acting as an industrial distillate hydrogen donor. The average molecular structure indicated that the parameters of the average molecular structure have a relationship with the HDA. R N/R A values closer to 1 indicate high HDA. Analysis of the hydrocarbon composition demonstrated that the total percentage of naphthenoaromatics, including naphthenebenzenes, dinaphthenebenzenes, and naphthenephenanthrenes, in the narrow fractions influenced the HDA of IDNFs.

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