The design of Co-Mn composite oxides catalysts derived from MOF is significant for catalytic combustion of toluene. Here, a series of M-Co_aMn_bO_x, with enhanced catalytic properties compared with that of M-Co₃O₄, were successfully prepared through pyrolysis of Mn-doped Co-MOF. The as-synthesized M-Co₁Mn₁O_x (Co:Mn = 1:1) exhibits an optimal catalytic activity with 90% toluene conversion reached at 227 ℃, which benefits from the increase of Co³⁺, O_ads and the synergistic effect between Mn and Co. According to the analysis of the in situ diffuse reflectance infrared Fourier transform spectroscopy, toluene could be degraded easier on M-Co₁Mn₁O_x with lower activation energy than M-Co₃O₄. The main intermediate products are benzaldehyde, benzoic acid, anhydride, and maleate species. Those findings reveal the value of Mn doping for improved activity of toluene oxidation on MOF derived Co₃O₄, which provide a feasible method for the construction of toluene-oxidation catalysts.

Highly efficient and robust electrocatalysts have been in urgent demand for oxygen evolution reaction (OER). For this purpose, high-cost carbon materials, such as graphene and carbon nanotubes, have been used as supports to metal oxides to enhance their catalytic activity. We report here a new Co₃O₄-based catalyst with nitrogen-doped porous carbon material as the support, prepared by pyrolysis of porous polyurea (PU) with Co(NO₃)₂ immobilized on its surface. To this end, PU was first synthesized, without any additive, through a very simple one-step precipitation polymerization of toluene diisocyanate in a binary mixture of H₂O-acetone at room temperature. By immersing PU in an aqueous solution of Co(NO₃)₂ at room temperature, a cobalt coordinated polymer composite, Co(NO₃)₂/PU, was obtained, which was heated at 500 ℃ in air for 2 h to get a hybrid, Co₃O₄/NC, consisting of Co₃O₄ nanocrystals and sp²-hybridized N-doped carbon. Using this Co₃O₄/NC as a catalyst in OER, a current density of 10 mA·cm^-2 was readily achieved with a low overpotential of 293 mV with a Tafel slope of 87 mV·dec^-1, a high catalytic activity. This high performance was well retained after 1000 recycled uses, demonstrating its good durability. This work provides therefore a facile yet simple pathway to fabrication of a new transition metal oxides-based N-doped carbon catalyst for OER with high performance.

Bioethanol, as a clean and renewable fuel, has gained increasing attention due to its major environmental benefits. Pervaporation (PV) is a promising and competitive technique for the recovery of ethanol from bioethanol fermentation systems due to the advantages of environmental friendliness, low energy consumption and easy coupling with fermentation process. The main challenge for the industrial application of ethanol perm-selective membranes is to break the trade-off effect between permeability and selectivity. As membrane is the heart of the pervaporation separation process, this article attempts to provide a comprehensive survey on the breakthroughs of ethanol perm-selective PV membranes from the perspectives of tailoring membrane materials to enhance PV separation performance. The research and development of polymeric and organic/inorganic hybrid membranes are reviewed to explore the fundamental structure–property-performance relationships. It is found that mixed matrix membranes with well-designed membrane structures offer the hope of better control overphysi-/chemical micro-environment and cavity/pore size as well as size distribution, which may provide both high permeability and membrane selectivity to break the trade-off effect. The tentative perspective on the possible future directions of ethanol perm-selective membranes is also briefly discussed, which may provide some insights in developing a new generation of high-performance PV membranes for ethanol recovery.

Anthraquinone dyes are a class of typical carcinogenic and hard-biodegradable organic pollutants. This study aimed to enhance the decolorization of anthraquinone dye by rationally designing an expected immobilized system. Reactive blue 4 (RB4) was used as a substrate model and a previous isolated dye-degrading strain Aspergillus flavus A5p1 was purposefully immobilized. Considering the effects of cell attachment and mass transfer, the polyurethane foam (PUF) with open pore structure was selected as the immobilization carrier. Results showed that the RB4 decolorization efficiency was significant enhanced after immobilization. Compared to the free mycelium system, the decolorization time of 200 mg·L^-1 RB4 was shortened from 48 h to 28 h by the PUF-immobilized cell system. Moreover, the PUF-immobilized system could tolerate RB4 up to 2000 mg·L^-1. In the packed bed bioreactor (PBBR), an average decolorization efficiency of 93.3% could be maintained by the PUF-immobilized system for 26 days. The decolorization process of RB4 was well described by the logistic equation and the degradation pathway was discussed. It was found that the higher specific growth rate of the PUF-immobilized cells was one of reasons for the enhanced decolorization. The good performance of the PUF-immobilized cell system would make it have potential application value for RB4 bioremediation.

Nowadays, efficient removal of antibiotic (e.g. tetracycline, TC) from water bodies has been of great global concern. Hereby, a novel Zn₂SnO₄/SnO₂@ZIF-8 photo-catalyst was first synthesized by a facile self-assembly in-situ growth method. Zn₂SnO₄/SnO₂@ZIF-8 exhibits a remarkable photocatalytic activity towards TC under visible-light driven with a rapid rate constant of 1.5×10^-2 min^-1, and a removal efficiency of 81.2%, which is superior to some catalysts in the literature. Importantly, the photocatalytic activity of Zn₂SnO₄/SnO₂@ZIF-8 could still remain ~77% after the fifth cycle, indicating its good stability and reusability. The remarkable performances of adsorption and photocatalytic were attributed to associative effects of catalytic activity of Zn₂SnO₄/SnO₂ and the unique porous nanostructure and stability of ZIF-8. This work could aid the future design and preparation of novel MOFs composite catalysts for efficient elimination of antibiotics from water.

Excellent mechanical properties are the prerequisite for the application of superhydrophobic polymer coatings. However, significantly improving the mechanical properties without affecting other properties such as hydrophobicity is a huge challenge. In this study, a superhydrophobic coating with excellent mechanical properties was prepared by spraying a mixture of polysiloxane resins based on three siloxane monomers, hexadecyltrimethoxysilane (HDTMS) modified nano-SiO₂ particles (SiO₂-HDTMS) and polystyrene-grafted halloysite nanotubes (HNTs-PS). SiO₂-HDTMS dispersed homogeneously in polysiloxane coatings and the water contact angle of corresponding coating exceeding 150°, achieving superhydrophobicity. The SiO₂-HDTMS/HNTs-PS/polysiloxane composite coatings showed excellent abrasion resistance with the water coating contact angle remaining above 150° after 90 abrasion cycles, indicating that HNTs-PS can significantly improve the mechanical properties of the coating without affecting the hydrophobic properties of the coating. The achieved coating also exhibited excellent antifouling and acid and alkali corrosion resistance. This work provides a convenient and ecologically friendly method to prepare superhydrophobic polysiloxane composite coating with excellent mechanical properties, which is promising in the application of anti-fouling, anti-corrosion, and oil–water separation etc.

The hydrodynamics and mixing during the nonaxisymmetry impingement of a micro-droplet and a sessile droplet of the same fluid are investigated by many-body dissipative particle dynamics (MDPD) simulation. In this work, the range of the impingement angle (θ_i) between the impinging droplet and the sessile droplet is 0°–60° and the contact angle is set as 45° or 124°. The droplets impingement and mixing behavior is analyzed based on the droplet internal flow field, the concentration distribution and the time scale of the decay of the kinetic energy of the impinging droplet. The dimensionless total mixing time (τ_m) is calculated by a modified mixing function. With the Weber number (We) ranging from 5.65 to 22.7 and the Ohnesorge number (Oh) ranging from 0.136 to 0.214, we find τ_m hardly changes with We and Oh. Whereas, θ_i and surface wettability are found to have a significant effect on τ_m. We find that θ_i has no clear effect on τ_m on a hydrophobic surface, while on the hydrophilic surface, τ_m increase with the θ_i. Thus, reducing the impinging angle is a valid method to shorten the τ_m.

Gasification of extraction residue (ER) from direct coal liquefaction with pulverized coal is an efficient way for the utilization of carbonaceous wastes, which improve the overall efficiency of direct coal liquefaction technology. The discharge characteristics of ER mixing with pulverized coal is important paraments for its gasification process, which is seldom studied in the literature. In this study, the discharge characteristics of the pulverized coal (M1) as well as its mixture with ER (M2) were systematically investigated in an atmospheric pressure partial fluidization silo with different fluidization apparent velocity. It was observed that although M2 is a viscous powder with lower flowability than M1, the mass flow rate of M2 is 65% higher than M1 at the 3.7 mm·s^-1 apparent gas velocity. M2 exhibits the properties of Geldart A type powder, which improves the mass flow rate and stability of the discharged material. The mass flow rate of both M1 and M2 first increases and then slowly decreases with the increase of apparent gas velocity of the fluidizing air, which means the discharge process of M1 and M2 can be optimized by the apparent gas velocity.

“Shuttle effect” is detrimental for maintaining the high capacity and cycling reversibility of lithium-sulfur batteries (LSBs). To inhibit polysulfide migration, N-doped carbon nanofibers (N-CNFs) membrane comprising TiO₂ nanoparticles (TiO₂/N-CNFs) is fabricated using an electrospinning-calcination method and further applied as interlayer in LSBs. The TiO₂/N-CNFs interlayer helps the battery to deliver a high specific capacity of 1155.2 mA·h·g^-1 at 0.2 C with high Coulombic efficiency, good rate capability and stability. When cycling at 0.5 C, a capacity retention rate of 62.4% is achieved over 300 cycles, which is higher than that of CNFs and TiO₂/CNFs counterparts. The excellent performance should mainly be attributed to the alleviated “shuttle effect” deriving from high polysulfide trapping ability of TiO₂ nanoparticles and N heteroatoms in interwoven CNFs.

Surface modification of natural cellulose fibers with nanomaterials is an effective strategy for producing functional textiles for multiple applications. A4-sized printing paper is a commonly used, cheap, and easily acquirable office supply which is mainly made of cellulose fibers. Here, we report green and simple nanofabrication of A4 paper to endow it with high capability for fragrance encapsulation and sustained release, and strong adsorption to indoor air pollutants. The method utilizes the sugar molecule of cellulose for in-situ growth of γ-cyclodextrin (γ-CD) metal–organic frameworks (MOFs) on A4 paper. The obtained γ-CD-MOF/A4 nanocomposites have superior specific surface area and high porous structure. The γ-CD-MOF/A4 nanocomposites can effectively encapsulate fragrant molecules through host–guest interaction. The γ-CD-MOF/A4 nanocomposites also show strong absorption capability to formaldehyde and carbon dioxide through the formation of hydrogen bonding and chemical bonds. These γ-CD-MOF/A4 nanocomposites combine the advantages of both A4 paper and γ-CD-MOF, which can be used in indoor air freshening and cleaning.

A double-effect reactive distillation (DERD) process was proposed for the production of propylene glycol methyl ether from propylene oxide and methanol to overcome the shortcoming of low selectivity and high-energy consumption in the tubular plug-flow reactor. A single-column reactive distillation (RD) process was conducted under optimized operating conditions based on sensitivity analysis as a reference. The results demonstrated that the proposed DERD process is able to achieve more than 95% selectivity of the desired product. After that, a design approach of the DERD process with an objective of the minimum operating cost was proposed to achieve further energy savings in the RD process. The proposed DERD configuration can provide a large energy-savings by totally utilization of the overhead vapor steam in the high-pressure RD column. A comparison of the single-column RD process revealed that the proposed DERD process can reduce the operating cost and the total annual cost of 25.3% and 30.7%, respectively, even though the total capital cost of DERD process is larger than that of the RD process.

Due to outstanding performance in cheminformatics, machine learning algorithms have been increasingly used to mine molecular properties and biomedical big data. The performance of machine learning models is known to critically depend on the selection of the hyper-parameter configuration. However, many studies either explored the optimal hyper-parameters per the grid searching method or employed arbitrarily selected hyper-parameters, which can easily lead to achieving a suboptimal hyper-parameter configuration. In this study, Hyperopt library embedding with the Bayesian optimization is employed to find optimal hyper-parameters for different machine learning algorithms. Six drug discovery datasets, including solubility, probe-likeness, hERG, Chagas disease, tuberculosis, and malaria, are used to compare different machine learning algorithms with ECFP6 fingerprints. This contribution aims to evaluate whether the Bernoulli Naïve Bayes, logistic linear regression, AdaBoost decision tree, random forest, support vector machine, and deep neural networks algorithms with optimized hyper-parameters can offer any improvement in testing as compared with the referenced models assessed by an array of metrics including AUC, F1-score, Cohen’s kappa, Matthews correlation coefficient, recall, precision, and accuracy. Based on the rank normalized score approach, the Hyperopt models achieve better or comparable performance on 33 out 36 models for different drug discovery datasets, showing significant improvement achieved by employing the Hyperopt library. The open-source code of all the 6 machine learning frameworks employed in the Hyperopt python package is provided to make this approach accessible to more scientists, who are not familiar with writing code.

Tonalid, an important fragrance ingredient with widespread application, was synthesized via two Friedel-Crafts reactions, which were catalyzed by AlCl₃. The traditional tonalid production was conducted in batch stirring tank reactors, suffering from low production capacity and the safety hazard of temperature runaway. To solve these problems, the continuous-flow technologies were developed for the high-efficiency and intrinsically safe synthesis of tonalid in microreactors. Catalyst AlCl₃ was neatly homogenized in proper solvents by forming complex with reactant, which was a necessary step for the continuous synthesis in microreactors. Several reaction conditions, including reactant molar ratio, catalyst concentration, temperature, and microchannel hydrodynamic diameter, were investigated for the two Friedel-Crafts reactions in microreactors. At optimized conditions, the yields of the two Friedel-Crafts reactions were 44.15% and 97.55%, respectively. In comparison with the batch reactors, the reaction times of these two reactions could both be reduced by nearly two thirds in microreactors at the similar yield.

β-lactam antibiotics in aquatic environment have severely damaged ecological stability and caused a series of environmental pollution problems to be solved urgently. Herein, a novel composite photocatalyst prepared by loading carbon dots (CDs) onto rod-like CoFe₂O₄ (CFO), which can effectively degrade amoxicillin (AMX) by photocatalytic/peroxymonosulfate (PMS) activation under visible light irradiation. The degradation results exhibits that the optimal degradation efficiency with 97.5% within 80 min is achievd by the CDs-CFO-5 composite. Such enhanced activity is ascribed to the introduction of CDs that effectively improves the separation efficiency of photogenerated electron pairs and creates new active sites as electron bridges that improve the photocatalytic performance. More importantly, a strong synergistic between CDs and photo-induced electrons generated from CFO can further activiate PMS to provide more SO₄^-· and ·OH radicals for boosting the degradation ability towards AMX. The present study aims to elucidate positive role of CDs in photocatalytic/peroxymonosulfate activation during the degradation reaction.

Investigations were conducted to purify crude Li₂CO₃ via direct carbonation with CO₂ at atmospheric pressure and pyrolysis with both water bath heating method and microwave heating method. The reaction kinetics of LiHCO₃ pyrolysis was studied and the effect of different operating conditions including initial concentration of LiHCO₃ solution, pyrolysis temperature and stirring speed on the purity of Li₂CO₃ was investigated to obtain the optimal operating conditions. Results showed that the effect law is similar in the two pyrolysis processes. The purity of the Li₂CO₃ increases firstly and then decreases with the increase of the initial concentration of LiHCO₃ solution and the stirring speed, while the purity of Li₂CO₃ first decreases and then increases with the increase of pyrolysis temperature. The product yield increases with the increase of initial concentration of LiHCO₃ solution and pyrolysis temperature and is essentially unaffected by the stirring speed. Under the optimal operating conditions, the purity of Li₂CO₃ can reach up to 99.86% and 99.81% in water bath heating and microwave heating process, respectively. In addition, the pyrolysis rate of microwave assisted pyrolysis is 6 times that of water bath heating process, indicating that the microwave heating technology can significantly improve pyrolysis efficiency and reduce energy consumption.

A series of SO₃-functional Brønsted acidic ionic liquids (SBAILs) were prepared to catalyze the N-formylation of aniline with DMF. The reaction conditions such as ionic liquid type, reaction temperature, catalyst loading and molar ratio of reactants were investigated. To the best of our knowledge, kinetic model for the N-formylation of aniline with DMF using SBAIL was firstly built and simulated. The studies on the reaction order of the reaction were evaluated by initial concentration method, and the kinetic parameters such as reaction rate constant and activation energy were proposed and used to explain the catalytic activities of the SBAILs catalysts. Accordingly, the recycling experiments showed that the SBAIL [Bsmim][HSO₄] can be easily recovered and reused with stable activity. Further, the temperature-controlled study emphasized that the ionic liquid was easy to be separated and environmentally friendly.

In this study, a MOF-derived bimetallic Co@NiO catalyst was synthesized and doped into MgH₂ to improve the hydrogen desorption and resorption kinetics. The Co@NiO catalyst decreased the onset dehydrogenation temperature of MgH₂ by 160 ℃, compared with un-doped MgH₂. The MgH₂ + 9% (mass) Co@NiO composite released 6.6% (mass) hydrogen in 350 s at 315 ℃ and uptook 5.4% (mass) hydrogen in 500 s at 165 ℃, showing greatly accelerated de/rehydrogenation rates. Besides, the desorption activation energy of MgH₂ + 9% (mass) Co@NiO was decreased to (93.8 ±8.4) kJ·mol^-1. Noteworthy, symbiotic Mg₂NiH₄/Mg₂CoH₅ clusters were in-situ formed from bimetallic precursors and inlaid on MgH₂ surface, which are considered as “multi-step hydrogen pumps”, and provides surface pathways for hydrogen absorption. Meanwhile, the introduced Mg₂NiH₄/Mg₂CoH₅ interfaces could provide numerous low energy barrier H diffusion channels, therefore accelerating the hydrogen release and uptake. This research proposes new insights to design high-efficiency bimetallic catalyst for MgH₂ hydrogen storage.

The bare amorphous Al₂O₃-AlPO₄ and Cs/Al₂O₃-AlPO₄ catalysts were developed for the aldol condensation of methyl acetate with formaldehyde to methyl acrylate. The structure and property of catalyst were characterized by XRD, XPS, BET, Pyridine-IR, FT-IR, ²⁷Al-MASNMR, NH₃-/CO₂-TPD and SEM. The correlation between structural features and acid-base properties was established, and the loading effect of the cesium species was investigated. Due to cooperative catalytic effects between the penta-coordinated Al and Al₂O₃, the weak-II acid and medium acid site densities and the product selectivity were improved. While the basic site densities of these catalysts were almost in proportion to the conversion of methyl acetate. The loaded Cs could form new basic sites and change the distribution of acid sites which further enhance the catalytic performance. As a result, the 10Cs/8AlP was proved to be an optimal catalyst with the yield and selectivity of 21.2% and 85% for methyl acrylate respectively. During the reaction, a deactivation behavior was observed on 10Cs/8AlP catalyst due to the carbon deposition, however, it could be regenerated by thermal treatment in the air atmosphere at 400 ℃.