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Developing bioactive materials for bone implants to enhance bone healing and bone growth has for years been the focus of clinical research. Barium titanate (BT) is an electroactive material that can generate electrical signals in response to applied mechanical forces. In this study, a BT piezoelectric ceramic coating was synthesized on the surface of a TC4 titanium alloy, forming a BT/TC4 material, and low-intensity pulsed ultrasound (LIPUS) was then applied as a mechanical stimulus. The combined effects on the biological responses of MC3T3-E1 cells were investigated. Results of scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction showed that an uniform nanospheres -shaped BT coating was formed on TC4 substrate. Piezoelectric behaviors were observed using piezoelectric force microscopy with the piezoelectric coefficient d33 of 0.42 pC/N. Electrochemical measures indicated that LIPUS-stimulated BT/TC4 materials could produce a microcurrent of approximately 10 μA/cm2. In vitro, the greatest osteogenesis (cell adhesion, proliferation, and osteogenic differentiation) was found in MC3T3-E1 cells when BT/TC4 was stimulated using LIPUS. Furthermore, the intracellular calcium ion concentration increased in these cells, possibly because opening of the L-type calcium ion channels was promoted and expression of the CaV1.2 protein was increased. Therefore, the piezoelectric BT/TC4 material with LIPUS loading synergistically promoted osteogenesis, rending it a potential treatment for early stage formation of reliable bone-implant contact., Graphical abstract Image 1, Highlights • BT piezoelectric ceramic coating was hydrothermally synthesized on the surface of TC4 titanium alloy to form BT/TC4 material. • The BT/TC4 material under ultrasound loading could produce a microcurrent of approximately 10 μA/cm2. • The piezoelectric BT/TC4 material with LIPUS loading synergistically promoted biological activity of MC3T3-E1 cells. • Electroactivity of BT/TC4 material stimulated by LIPUS loading promoted the intracellular Ca2+ influx in MC3T3-E1 cells.

To solve the poor sustainability of electroactive stimulation in clinical therapy, a strategy of combining a piezoelectric BaTiO3-coated Ti6Al4V scaffold and low-intensity pulsed ultrasound (LIPUS) was unveiled and named here as piezodynamic therapy. Thus, cell behavior could be regulated phenomenally by force and electricity simultaneously. First, BaTiO3 was deposited uniformly on the surface of the three-dimensional (3D) printed porous Ti6Al4V scaffold, which endowed the scaffold with excellent force-electricity responsiveness under pulsed ultrasound exposure. The results of live/dead staining, cell scanning electron microscopy, and F-actin staining showed that cells had better viability, better pseudo-foot adhesion, and more muscular actin bundles when they underwent the piezodynamic effect of ultrasound and piezoelectric coating. This piezodynamic therapy activated more mitochondria at the initial stage that intervened in the cell cycle by promoting cells' proliferation and weakened the apoptotic damage. The quantitative real-time polymerase chain reaction data further confirmed that the costimulation of the ultrasound and the piezoelectric scaffolds could trigger adequate current to upregulated the expression of osteogenic-related genes. The continuous electric cues could be generated by the BaTiO3-coated scaffold and intermittent LIPUS stimulation; thereon, more efficient bone healing would be promoted by piezodynamic therapy in future treatment.

Herein, catalytic aqueous phase photoreforming of cellulose was carried out over Pt/m-TiO2 (i.e., mixed phase of anatase and rutile) and Pt/anatase catalysts to investigate the effect of the TiO2 support structure and Pt loading on the production of H2. The effect of the TiO2 support on the properties of the resulting Pt/TiO2 catalysts (such as actual Pt loading and BET surface area) was not significant. At low Pt loading of 0.16 wt.%, the TiO2 supports affected the sub-nanometre Pt structures which was confirmed by the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) characterisation (using CO as the probe). Conversely, the effect of TiO2 supports on larger Pt particles (on 1 wt.% catalysts) was insignificant possibly due to the reduced effect of restructuration of bigger Pt particles on the TiO2 supports. With an increase in Pt loading from 0.16 wt% to 1.00 wt.%, the normalised H2 production rate (with respect to the actual supported Pt amount and specific surface area of the catalysts) showed a decreasing trend over the two types of the catalysts, i.e., from 10.6 to 1.4 μmol h−1 m−2 mgPt−1 for Pt/m-TiO2, and from 8.5 to 1.2 μmol h−1 m−2 mgPt−1 for Pt/anatase. Specifically, large Pt particle sizes reduced the CO2/H2 production from cellulose photoreforming over both Pt/m-TiO2 and Pt/anatase catalysts, indicting an important role played by Pt particle size in photoreforming. Interestingly, in this study, the m-TiO2 supported catalysts only showed the benefits of enhanced charge separation across the phase junction in producing H2 with small Pt particles (at sub-nanometre), whilst, when large Pt particles (at around 1–2 nm) were supported, such a benefit was not significant in cellulose photoreforming. The promoting effect of small, sub-nm particles is attributed to the better capture of photoelectrons from bulk TiO2 and better activity of H+ coupling on small Pt particle. Further fundamental study on such guest-host interactions is devised to optimise Pt/TiO2 catalysts for improving H2 production from photoreforming reactions.

The stability of catalysts in dry reforming of methane (DRM) is a known issue. In this paper an encapsulation strategy has been employed to improve the stability compared with conventional impregnation methods. Herein, nickel nanoparticles encapsulated in silicalite-1 were prepared using a range of methods including post treatment, direct hydrothermal and seed-directed methods to investigate the effect of synthesis protocol on the properties of catalysts, such as degree of encapsulation and Ni dispersion, and anti-coking/-sintering performance in DRM. The Ni@SiO2-S1 catalysts obtained by the seed-directed synthesis presented the full encapsulation of Ni NPs by the zeolite framework with small particle sizes (∼2.9 nm) and strong metal-support interaction, which could sterically hinder the migration/aggregation of Ni NPs and carbon deposition. Therefore, Ni@SiO2-S1 showed stable CO2/CH4 conversions of 80% and 73%, respectively, with negligible metal sintering and coking deposition (∼0.5 wt%) over 28 h, which outperformed the other catalysts prepared. In contrast, the catalysts developed by the post-treatment and ethylenediamine-protected hydrothermal methods showed the co-existence of Ni phase on the internal and external surfaces, i.e. incomplete encapsulation, with large Ni particles, contributing to Ni sintering and coking. The correlation of the synthesis-structure-performance in this study sheds light on the design of coking-/sintering-resistant encapsulated catalysts for DRM.

A novel ZSM-5@SiC structured catalytic packing (ZSM-5@SiC SCP) was recently proposed to combine catalysis and separation functionality in one unit for reactive distillation (RD) towards the synthesis of green solvent ethyl lactate (EL). This work conducts life cycle assessment (LCA) and economic analysis for the RD process to identify relevant hot spots and suggest further development. Based on the cradle-to-gate LCA, the major environmental hot spots of the proposed RD process based on SCP are identified as in the section of raw materials extraction and RD. Compared to the petrochemical counterparts, bio-derived lactic acid and ethanol show the advantage to reduce carbon emission and resource depletion, but having significant impacts on aggravate stratospheric ozone depletion and land use especially. LCA results also show that preparation ZSM-5@SiC SCP creates environmental impacts due to the usage of electricity and relevant raw materials. Comparative LCA and economic analysis were conducted for the RD processes using ZSM-5@SiC SCP and seepage catalytic packing internal (SCPI), respectively, and a conventional process with separated reaction and separation unit operations. The findings suggest that compared to the conventional process RD processes can reduce greenhouse gas emissions and total annual cost (TAC) due to process intensification. The process employing ZSM-5@SiC SCP incurs a higher TAC than that based on SCPI (with resin catalysts), which is due to its comparatively low catalytic activity, requiring more ZSM-5@SiC SCP and higher column to achieve the production target.

This work presents an efficient method of supporting zirconia (ZrO2) on –COOH functionalized multi-walled carbon nanotubes (ZrO2/MWCNTs(C)) via a microwave (MW)-assisted method, which can be used as an efficient catalyst for converting fructose to 5-HMF. The developed composite by the MW-assisted route shows highly dispersed ZrO2 with small sizes of 4–5 nm on the carbon support, which could not be achieved the conventional hydrothermal synthesis. Characterization shows a unique zirconia amorphous structure which was ascribed to the special interaction between the carbon support and MW irradiation. Specifically, MWCNTs were heated selectively due to their strong MW-absorbing ability, which led to the formation of microscopic “hot spots”, enabling rapid synthesis (8 min) of highly dispersed ZrO2 with smaller sizes on the hot surface of MWCNTs. Conversely, under conventional heating, the nucleation rate of ZrO2 was slow and prone to form agglomerated particles on the carbon support. The amorphous ZrO2 contributed to the excellent activity of ZrO2/MWCNTs(C) in fructose conversion to 5-HMF. In detail, fructose conversion and 5-HMF yield were achieved at ~72.8% and ~62.9%, respectively, for the catalyst prepared by the MW method, whilst they are only about 24.7% and 15.7% over the catalyst prepared by the conventional hydrothermal synthesis.

The aim of this study was to evaluate the biocompatibility and osteogenic potential of a Zeolite Socony Mobil-5 (ZSM-5) coating on a Ti-24 Nb-4 Zr-7.9 Sn (Ti-2448) surface. ZSM-5-modified Ti-2448 (ZSM-5/Ti-2448) and Ti-2448 (control) groups were employed. The physical and chemical properties of the two types of samples were evaluated by scanning electron microscopy, Fourier-transform infrared spectroscopy, nitrogen adsorption/desorption, and contact angle methods. The surface of the ZSM-5/Ti-2448 was rougher than that of the original Ti-2448, while the contact angle of the ZSM-5/Ti-2448 was smaller than that of Ti-2448. In addition, the ZSM-5/Ti-2448 largely increased the specific surface area and introduced silanol groups. A bone-like apatite layer could be formed on the surface of ZSM-5/Ti-2448 after 14 days of incubation in a simulated body fluid. ZSM-5/Ti-2448 was not cytotoxic. The number and alkaline phosphatase (ALP) activity of osteoblasts on ZSM-5/Ti-2448 were significantly higher than those on Ti-2448 surfaces, obtained in vitro using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide and ALP activity assays. Few inflammatory cells were observed around ZSM-5/Ti-2448 after insertion into the femurs of Japanese white rabbits after 4, 12, and 26 weeks through hematoxylin–eosin staining. The average gray scale of transforming growth factor-β1 (TGF-β1) on ZSM-5/Ti-2448 peaked earlier than that on Ti-2448, according to immunohistochemical staining. These results indicate that ZSM-5/Ti-2448 has a good biocompatibility and improved early osteogenic potential compared to a noncoated Ti-2448.

This study presents a novel combination of microwave irradiation and structured zeolite/SiC foam catalyst to improve the methanol-to-hydrocarbons (MTH) process as well as its environmental sustainability. Accordingly, ZSM-5/SiC foam was studied under microwave irradiation at various reaction temperatures (400–550 °C) and space velocities (8 and 12 h−1) and compared to conventional ZSM-5 pellets. ZSM-5/SiC foam promoted higher selectivity towards C1−C5 hydrocarbons (∼95%) and particularly propylene (∼40% at 400 °C and 8 h−1) compared to ZSM-5 pellets (∼40% and 6–9%, respectively) due to the enhanced mass and heat transfers. The microwave-assisted MTH process with both the structured catalyst and pellets was also assessed on the environmental sustainability via life cycle assessment in comparison with the conventionally-heat process with the structured catalyst. The results showed that the microwave-based process with the structured catalyst could reduce the environmental impacts of propylene production by 22–30% compared to the conventionally-heated process with the same catalyst.

Bone defect repair at load-bearing sites is a challenging clinical problem for orthopedists. Defect reconstruction with implants is the most common treatment; however, it requires the implant to have good mechanical properties and the capacity to promote bone formation. In recent years, the piezoelectric effect, in which electrical activity can be generated due to mechanical deformation, of native bone, which promotes bone formation, has been increasingly valued. Therefore, implants with piezoelectric effects have also attracted great attention from orthopedists. In this study, we developed a bioactive composite scaffold consisting of BaTiO3, a piezoelectric ceramic material, coated on porous Ti6Al4V. This composite scaffold showed not only appropriate mechanical properties, sufficient bone and blood vessel ingrowth space, and a suitable material surface topography but also a reconstructed electromagnetic microenvironment. The osteoconductive and osteoinductive properties of the scaffold were reflected by the proliferation, migration, and osteogenic differentiation of mesenchymal stem cells. The ability of the scaffold to support vascularization was reflected by the proliferation and migration of human umbilical vein endothelial cells and their secretion of VEGF and PDGF-BB. A well-established sheep spinal fusion model was used to evaluate bony fusion in vivo. Sheep underwent implantation with different scaffolds, and X-ray, micro-computed tomography, van Gieson staining, and elemental energy-dispersive spectroscopy were used to analyze bone formation. Isolated cervical angiography and visualization analysis were used to assess angiogenesis at 4 and 8 months after transplantation. The results of cellular and animal studies showed that the piezoelectric effect could significantly reinforce osteogenesis and angiogenesis. Furthermore, we also discuss the molecular mechanism by which the piezoelectric effect promotes osteogenic differentiation and vascularization. In summary, Ti6Al4V scaffold coated with BaTiO3 is a promising composite biomaterial for repairing bone defects, especially at load-bearing sites, that may have great clinical translation potential.

Biomedical materials with effective hemostatic properties are in great demand in clinical and battlefield application for severe hemorrhage control. In this study, nearly amorphous chitin is obtained by treating α-chitin with superfine grinding, and the solubility of chitin in hexafluoro-2-propanol (HFIP) is significantly increased. Chitin and gelatin mixtures are prepared by adding different amount of gelatin to the 8 mg mL

Plasma-catalysis systems are complex and require further understanding to advance the technology. Herein, CO poisoning in CO2 hydrogenation over supported ruthenium (Ru) catalysts in a nonthermal p...

Hydrogen (H2) production from photocatalytic reforming of cellulose is a promising way for sustainable H2 to be generated. Herein, we report a systematic study of the photocatalytic reforming of cellulose over Pt/m-TiO2 (i.e. mixed TiO2, 80% of anatase and 20% of rutile) catalysts in water. The optimum operation condition was established by studying the effect of Pt loading, catalyst concentration, cellulose concentration and reaction temperature on the gas production rate of H2 (rH2) and CO2 (rCO2), suggesting an optimum operation condition at 40 °C with 1.0 g·L−1 of cellulose and 0.75 g·L−1 of 0.16-Pt/m-TiO2 catalyst (with 0.16 wt% Pt loadting) to achieve a relatively sound photocatalytic performance with rH2 = 9.95 μmol·h−1. It is also shown that although the photoreforming of cellulose was operated at a relatively mild condition (i.e. with an UV-A lamp irradiation at 40 °C in the aqueous system), a low loading of Pt at ~ 0.16 wt% on m-TiO2 could promote the H2 production effectively. Additionally, by comparing the reaction order expressed from both rH2 (a1) and rCO2 (a2) with respect to cellulose and water, the possible mechanism of H2 production was proposed.

A novel post-synthetic method combining the microwave (MW)-assisted dealumination and hydrothermal (HT) alkaline treatment for obtaining mesoporous Y zeolite catalysts is presented. In the first-step MW-assisted dealumination of the pristine Y zeolite, both the mineral acid (i.e. hydrochloric acid, HCl) and organic carboxylic acids (e.g. oxalic and diethylenetriaminepentaacetic acid) were used (all at 0.16 M), and their effects on the physical and chemical properties of the resulting modified zeolites (after the identical HT alkaline treatment using 0.2 M sodium hydroxide solution) are studied in detail by comprehensive characterisation of the bulk silicon-to-aluminium (SAR) ratio, crystallinity and textural properties. The findings show that, in the developed sequential method, (i) HCl was only effective to achieve the hydrolysis of the zeolite, (ii) carboxylic acids with the function of chelation was very capable of extracting Al species and creating mesopores, and (iii) the mesopores formation is a function of the number of coordination sites in the carboxylic acid. The hierarchical feature of the mesopores in the modified zeolites (using carboxylic acids) was probed by the model reaction of aldol condensation of 1-heptanal with benzaldehyde for the selective formation of jasminaldehyde. The normalised selectivity to jasminaldehyde (with respect to the strong acidity) was proportionally related to the specific mesopores volume of the zeolites, revealing hierarchical porous networks in the relevant modified Y zeolites and indicating the effect of hierarchical mesopores in the zeolites on their catalytic performance.

The kinetics on structured catalysts is very important for the design and application of catalytic distillation processes. While the kinetic studies in the previous literatures were focused on the intrinsic kinetics using batch reactors that had eliminated the fluid flow situations, this work successfully utilized SiC foam materials to develop a structured catalyst with a ZSM-5 zeolite coating, and the kinetics were characterized by the synthesis of n-amyl acetate. A comparative study on the effect of the temperature (378.15–403.15 K) and flow rate (10.77–30.91 L h−1) revealed that the kinetics exhibited a strong fluid flow characteristic (e.g., Re number) dependence, and the rate of liquid renewal may be the cause of the reaction process over the structured catalyst. The reaction kinetics was modeled and regressed as a pseudo homogeneous model for both structured and particulate catalysts, and the model showed good agreement with experiments. The obtained models can be used for the analysis and guidance of catalytic distillation processes with structured catalytic packing.

This work presents a two-step method for preparing structured Cobalt-Manganese Oxides nano-sheet (CMO) on SiC nano-whisker (SNW) modified SiC foam support (i.e. CMO@SNW@SiC) and its application to catalytic combustion of toluene. Firstly, SiC nano-whiskers were synthesized on the surface of SiC foam via carbothermal reduction to increase the specific surface area of the resulting structured support (SNW@SiC). Then, CMO were grown on SNW@SiC by hydrothermal synthesis. SNW@SiC provide more surface area, and the nano-sized SiO2/SiCxOy layer on the surface of the SNW promotes the redox reaction of the reactants on the surface, thereby ensuring the directional growth of CMO on SNW@SiC. Compared to the bare SiC foam, CMO loading was increased 67.5% on SNW@SiC. Analysis methods such as H2-TPR, O2-TPD and XPS prove that the redox ability of the CMO on SNW is similar to that of the powder CMO. Toluene catalytic combustion was used as a probe reaction to evaluate catalytic activity. The results show that the CMO@SNW@SiC catalyst could lower the light-off temperature compared to the CMO supported on SiC foam catalyst, which was equivalent to the bulk catalyst (CMO-24h). At the same time, in comparison with the bulk CMO catalyst, the CMO@SNW@SiC catalyst possessed a higher geometric external surface area, which promoted complete conversion of toluene at lower temperatures. In addition, the stability test shows that the CMO@SNW@SiC catalyst also had very good thermal stability and hydrothermal stability as well. The work provided not only the highly performed catalytic oxidation catalyst, but also presented a generic strategy for improving the design of structured catalysts.Keywords: structured catalyst; porous SiC foam; SiC nano-whiskers; cobalt-manganese oxides; catalytic combustion

Ethyl lactate is a promising green solvent, which can be produced via esterification of biomass derived lactic acid and ethanol. Herein, we report the development of highly active and stable polyoxometalates (POMs) supported on zeolite catalysts for synthesis of ethyl lactate. Repetitive stability tests were performed using the developed catalysts, and comparative characterization of the fresh and used catalysts was performed to understand the changes in the physicochemical properties of the catalysts. It was found that low-silica Y zeolites (silicon-to-aluminum ratio, SAR, of 2 and 5) are prone to be dealuminated (by lactic acid) under the reaction conditions, and thus being not suitable to be used as the catalyst support. Direct support of 12-tungstophosphoric acid (by impregnation) on high-silica Y zeolite (SAR40) led to deactivation during catalysis due to 12-tungstophosphoric acid leaching. This issue was solved by surface modification of the high-silica Y zeolite using cesium (Cs) ions before impregnation of 12-tungstophosphoric acid because the formed cesium phosphotungstate is insoluble in the reaction. As a result, a stable composite catalyst of Cs exchanged 12-tungstophosphoric acid supported on high-silica mesoporous Y was developed, which showed good reusability. In detail, after seven cyclic tests, the physiochemical properties of the catalyst and the catalytic performance remained relatively stable, e.g., the yield of ethyl lactate remained at around 29.6%. Findings of the study show that the stability of the zeolitic support and the support heteropolyacid are equally important for obtaining a stable catalyst for ethyl lactate synthesis via esterification.

Oxidative dehydrogenation of butenes to butadiene is a highly exothermic and diffusion-controlled reaction. The problems of high adiabatic temperature rise and pressure drop, low gas velocity and conversion, as well as high consumption of water exist in the conventional reactors. In order to ease these problems, SiC foam supporting ZnFe2O4-α-Fe2O3 (ZnFe2O4-α-Fe2O3/SiC foam) structured catalyst was prepared by a slurry-coating method. Its performance was systematically studied with varied reaction temperature, oxygen/1-butene molar ratio, steam/1-butene molar ratio and 1-butene gaseous hourly space velocity (GHSV), respectively. The results showed that the 1-butene conversion and butadiene selectivity over the structured catalyst could reach about 87% and 91%, respectively, at a 1-butene GHSV of 300 h−1, and even at a 1-butene GHSV of 600 h−1, the conversion could still maintain at 78%, which was much better than that of the particulate catalysts. In addition, compared to the particle packed bed, the structured bed showed lower temperature rise and nearly isothermic, could lower the consumption of water and allowed to be operated with a wider range of O2/1-butene molar ratio and a much higher 1-butene GHSV, due to its better process intensification capacity.

In this study, Al2O3-washcoated SiC (Al2O3–SiC) foams and Al2O3 powder were employed as the supports of a Ni catalyst for the liquid-phase hydrogenation of benzaldehyde. A series of Ni/Al2O3–SiC foam catalysts and Ni/Al2O3 powder catalysts with a Ni loading from 10 wt% to 37 wt% of the weight of Al2O3 were first prepared by a deposition–precipitation (DP) method. The catalytic activity and recyclability of both kinds of catalysts were then compared. Although it had a smaller accessible surface area with the reactant, the foam catalyst with a Ni loading of 16 wt% exhibited a slightly higher conversion of benzaldehyde after 6 h (of 99.3%) in comparison with the Ni/Al2O3 catalyst with identical Ni loading (conversion of 97.5%). When the Ni loading increased from 16 wt% to 37 wt%, the reaction rate obtained with the foam catalyst increased significantly from 0.108 to 0.204 mol L−1 h−1, whereas the reaction rate obtained with the powder catalyst increased from 0.106 to 0.123 mol L−1 h−1. Furthermore, the specific activity (moles of benzaldehyde consumed by 1 g min−1 of Ni) of the foam catalyst with a Ni loading above 30 wt% was superior to that of the powder catalyst because of its smaller Ni-particle size and higher mass-transfer rate. The foam catalyst displayed a high recyclability as a function of run times owing to the strong interaction between the Ni component and the Al2O3 coating. The conversion of benzaldehyde over the foam catalyst remained almost unchanged after being used 8 times. In comparison, a drop of 43% in the conversion of benzaldehyde with the powder catalyst was observed after being used 7 times due to the leaching of the Ni component.

Structured foam catalysts are technologies which address challenges in catalytic processes due to the mass and heat transfer limitations. In this work, ZSM-5 coated silicon carbide (SiC) foams were prepared by a dispersion-based method, resulting in a thin and uniform zeolite layer on the foam support (i.e. ZSM-5/SiC foam catalysts). A comparative study of catalytic cracking of n-hexane was studied over ZSM-5/SiC foam and ZSM-5 pellets catalysts at space velocities of 4–40 h−1, showing the improved n-hexane conversion, total selectivity to C2–C4 olefins and anti-deactivation performance, especially at the relatively high space velocities (>10 h−1), achieved by the ZSM-5/SiC foam catalysts. The light olefin yield obtained by the ZSM-5/SiC foam catalyst (with 45 ppi cell density) was almost five times higher than that by the conventional ZSM-5 pellets. A detailed analysis reveals that the specific surface area of SiC foams has the significant effect on the coating quality, and hence the catalytic performance in the cracking reaction.

Pore network is regarded as one of the most important aspects of FCC (Fluid Catalytic Cracking) catalysts for delivering reactants to active sites and transporting out products, and the structure of which can significantly influence the process efficiency. In this work, six characterization methods complementing each other were employed to study the full-scale pore structure (0.4 nm − 20 µm) of fresh FCC particles, especially the X-ray computed tomography (CT) and focused ion beam-scanning electron microscope (FIB-SEM). To focus on nano-scale pores, 3D reconstruction of a whole FCC particle was achieved based on nano-CT, from which the pore network model (PNM) was successfully extracted. Then, permeability simulations along different directions and through various sub-volumes were carried out to demonstrate the anisotropy and heterogeneity of pore structure, respectively. It was also found that the tortuosity of the pores distributed in the outer layer of the FCC particle was more significant than that in the central part of the particle, which could be the mass transfer limiting region during catalysis. Comprehensive acknowledgment of pore structure provides guidance for the optimization of the design of FCC particles, and the multi-scale characterization strategy is a generic strategy for in-depth investigation of structured porous materials.

Distillation reactor is one of the important equipment to improve the reaction conversion limited by the chemical equilibrium, however, the design of distillation reactor in industrial scale is still challenging due to the lack of efficient catalytic packing with corresponding kinetics. This work developed the novel catalytic packing consists of the structured ZSM-5@SiC foam catalyst and corrugated sheet, which used in distillation reactor for synthesis of ethyl levulinate (EL). The kinetic of structured ZSM-5@SiC foam catalyst was measured and model regarding the “structure factor” of ZSM-5@SiC catalyst and fluid flow conditions. Furthermore, the design of distillation reactor in industrial scale has been performed based on the developed kinetics, which demonstrated an excellent performance in the designed distillation reactor (EL yield 37.65% with energy consumption 3695 kJ/kg) are achieved. X-ray CT characterization revealed that the ZSM-5 coating thickness has the significantly effects on the kinetics and performances of distillation reactor.

We report a low-cost, highly energy efficient microwave-assisted chelation (MWAC) method, which enabled the post-synthetic modification of synthetic zeolites for adopting hierarchical structures within minutes. Exemplified by Zeolite Y, hierarchical Y zeolites prepared in this way showed exceptional specific external surface areas of >300 m2 g−1 and mesopore volumes of >0.46 cm3 g−1. Comparative assessments revealed that developed zeolites have shown significantly improved catalytic activities for catalysis involving large substrates, such as catalytic cracking and hydrocracking of plastics.

Mesoporous Y zeolites were prepared comparatively using the bottom-up templating (with carbon nanotubes, CNTs, and nanocrystalline cellulose, NCC, as the templates) and the top-down post-synthetic treatment (with the sequential chemical and alkaline treatment) methods and characterised comprehensively using various techniques. The relevant findings show that the mesoporous Y zeolites with the intercrystal mesoporosity were prepared by the templating methods, and the NCC is the more effective, economic and sustainable hard template than the CNTs for promoting the formation of intercrystal mesoporosity. While for the post-synthetic strategy, the microwave (MW)-assisted chemical treatment (using ethylenediaminetetraacetic acid, EDTA, as the chemical agent for dealumination) was much more effective than the conventional hydrothermal (HT) treatment for introducing intracrystalline mesoporosity under the comparable condition, e.g. the external surface area: 287 m2 g−1 by 1 min MW treatment vs. 205 m2 g−1 by 6 h HT treatment. The prepared mesoporous Y zeolites, along with the parent Y, were assessed using the catalytic cracking of 1,3,5 triisopriopylbenzene (TiPBz). It was found that the well-developed intracrystalline mesoporosity promoted by the effective MW-assisted post-synthesis method is highly beneficial to the catalysis involving the bulky molecules, and accordingly showed the comparatively best catalytic performance (regarding the conversion and selectivity) among all zeolites under study in this work.

Bone defect repair at load-bearing sites is a challenging clinical problem for orthopedists. Defect reconstruction with implants is the most common treatment; however, it requires the implant to have good mechanical properties and the capacity to promote bone formation. In recent years, the piezoelectric effect, in which electrical activity can be generated due to mechanical deformation, of native bone, which promotes bone formation, has been increasingly valued. Therefore, implants with piezoelectric effects have also attracted great attention from orthopedists. In this study, we developed a bioactive composite scaffold consisting of BaTiO

ZSM‐5 zeolite nanoboxes with accessible meso‐micro‐pore architecture and strong acid sites are important in relevant heterogeneous catalysis suffering from mass transfer limitations and weak acidities. Rational design of parent zeolites with concentrated and non‐protective coordination of Al species can facilitate post‐synthetic treatment to produce mesoporous ZSM‐5 nanoboxes. In this work, a simple and effective method was developed to convert parent MFI zeolites with tetrahedral extra‐framework Al into Al‐enriched mesoporous ZSM‐5 nanoboxes with low silicon‐to‐aluminium ratios of ≈16. The parent MFI zeolite was prepared by rapid ageing of the zeolite sol gel synthesis mixture. The accessibility to the meso‐micro‐porous intra‐crystalline network was probed systematically by comparative pulsed field gradient nuclear magnetic resonance diffusion measurements, which, together with the strong acidity of nanoboxes, provided superb catalytic activity and longevity in hydrocarbon cracking for propylene production., ZSM‐5 nanoboxes with low SARs: Rapid ageing of a sol gel synthesis mixture produces a parent zeolite with tetrahedral extra framework Al and a low silicon‐to‐aluminium ratio (SAR) value of ≈12, which is transformed to mesoporous ZSM‐5 nanoboxes with low SARs of ≈16 during post‐synthetic TPAOH treatment. The mesoporous ZSM‐5 nanoboxes show comparatively enhanced mass transfer ability, catalytic cracking activity and longevity.

In this work, titanosilicate MFI (TS-1) crystals with different Si/Ti ratio were treated with tetrapropylamonium hydroxide (TPAOH) solution of different concentrations. The results showed that the properties – crystal structure, titanium position, secondary pore structure and volume – of the treated samples strongly depend on the Si/Ti ratio of the parent TS-1 sample and the TPAOH concentration. For instance, high TPAOH concentration is necessary to induce titanium re-insertion into framework position and to create inter-connected open meso/macropore in TS-1 with low Si/Ti ratio. On the contrary, TPAOH treatment even at high concentration was found to be ineffective in the post-synthesis treatment of low titanium containing TS-1 samples and result in a phase change from orthorhombic to monoclinic. The post-treated high titanium containing and inter-connected secondary pore TS-1 samples exhibited higher activity for cyclohexene epoxidation than the parent TS-1 sample with similar Si/Ti. This technique provides a controlled way of mesopore creation in TS-1 materials, which may be extended to other titanium base microporous materials.

For large segmental bone defects, porous titanium scaffolds have some advantages, however, they lack electrical activity which hinders their further use. In this study, a barium titanate (BaTiO3) piezoelectric ceramic was used to modify the surface of a porous Ti6Al4V scaffold (pTi), which was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and roughness and water contact angle analyses. Low intensity pulsed ultrasound (LIPUS) was applied in vitro and in vivo study. The activity of bone marrow mesenchymal stem cells, including adhesion, proliferation, and gene expression, was significantly superior in the BaTiO3/pTi, pTi + LIPUS, and BaTiO3/pTi + LIPUS groups than in the pTi group. The activity was also higher in the BaTiO3/pTi + LIPUS group than in the BaTiO3/pTi and pTi + LIPUS groups. Additionally, micro-computed tomography, the mineral apposition rate, histomorphology, and the peak pull-out load showed that these scaffold conditions significantly enhanced osteogenesis and osseointegration 6 and 12 weeks after implantation in large segmental bone defects in the radius of rabbits compared with those resulting from the pTi condition. Consequently, the improved osteogenesis and osseointegration make the BaTiO3/pTi + LIPUS a promising method to promote bone regeneration in large segmental bone defects for clinical application., Graphical abstract Image 1, Highlights • BaTiO3 coating was successfully fabricated by a wet chemical method on the surface of porous Ti6Al4V scaffolds. • BaTiO3 coating showed better surface hydrophilicity and roughness than pure porous Ti6Al4V scaffolds. • BaTiO3 coating improved the biological behavior of BMSCs in vitro and promoted the formation of new bones in vivo. • LIPUS activated piezoelectric effect of BaTiO3 coating, enhanced cell viability in vitro and promoted osteogenesis in vivo. • BaTiO3/pTi + LIPUS conditions showed promising potential as a method to repair long bone defects for clinical application.

ZSM-5 zeolite coating supported on SiC foams was prepared by a precursor dispersion-secondary growth method and the resulting structured ZSM-5/SiC foam catalyst was used for the proof-of-concept study of catalytic bio-oils upgrading (i.e. deoxygenation of the model compounds of methanol and anisole) in reference to ZSM-5 catalyst pellets. A layer of ZSM-5 coating with inter-crystal porosity on SiC foams was produced by curing the zeolite precursor thermally at 80 °C. The use of SiC foam as the zeolite support significantly improved transport phenomena compared to the packed-bed using ZSM-5 pellets, explaining the comparatively good catalytic performance achieved by the structured ZSM-5/SiC foam catalyst. In comparison with the ZSM-5 pellets, the ZSM-5/SiC foam catalyst showed 100.0% methanol conversion (at the weight hourly space velocity, WHSV, of 8 h–1) and 100.0% anisole conversion (at WHSV =5 h−1) at the initial stage of the processes, while only about 3% were obtained for the ZSM-5 pellets, under the same conditions. Based on the comparative analysis of the characterisation data on the fresh and spent catalysts, the deactivation mechanisms of the ZSM-5/SiC and the ZSM-5 pellet catalysts were explained. The process intensification using SiC foam to support ZSM-5 improved the global gas-to-solid mass transfer notably, and hence mitigating the pore blocking due to the carbon deposition on the external surface of supported ZSM-5.

Mesoporous Y zeolites were prepared by the sequential chemical dealumination (using chelating agents such as ethylenediaminetetraacetic acid, H4EDTA, and citric acid aqueous solutions) and alkaline desilication (using sodium hydroxide, NaOH, aqueous solutions) treatments. Specifically, the ultrasound-assisted alkaline treatment (i.e., ultrasonic treatment) was proposed as the alternative to conventional alkaline treatments which are performed under hydrothermal conditions. In comparison with the hydrothermal alkaline treatment, the ultrasonic treatment showed the comparatively enhanced efficiency (with the reduced treatment time, i.e., 5 min vs. 30 min, all with 0.2 mol·L−1 NaOH at 65°C) in treating the deal-uminated Y zeolites for creating mesoporosity. For example, after the treatment of a dealuminated zeolite Y (using 0.1 mol·L−1 H4EDTA at 100°C for 6 h), the ultrasonic treatment produced the mesoporous zeolite Y with the specific external surface area (Sexternal) of 160 m2·g·−1and mesopore volume (Vmeso) of 0.22 cm3·g−1, being slightly higher than that by the conventional method (i.e., Sextemal= 128 m2·g−1 and Vmeso = 0.19 cm3·g−1). The acidic property and catalytic activity (in catalytic cracking of n-octane) of mesoporous Y zeolites obtained by the two methods were comparable. The ultrasonic desilication treatment was found to be generic, also being effective to treat the dealuminated Y zeolites by citric acid. Additionally, the first step of chemical dealumination treatment was crucial to enable the effective creation of mesopores in the parent Y zeolite (with a silicon-to-aluminium ratio, Si/Al = 2.6) regardless of the subsequent alkaline desilication treatment (i.e., ultrasonic or hydrothermal). Therefore, appropriate selection of the condition of the chemical dealumination treatment based on the property of parent zeolites, such as Si/Al ratio and crystallinity, is important for making mesoporous zeolites effectively.

Carbon dioxide (CO2) hydrogenation to value-added molecules is an attractive way to reduce CO2 emission via upgrading. Herein, non-thermal plasma (NTP) activated CO2 hydrogenation over Ru/MgAl layered double hydroxide (LDH) catalysts was performed. The catalysis under the NTP conditions enabled significantly higher CO2 conversions (∼85 %) and CH4 yield (∼84 %) at relatively low temperatures compared with the conventional thermally activated catalysis. Regarding the catalyst preparation, it was found that the reduction temperature can affect the chemical state of the metal and metal-support interaction significantly, and thus altering the activity of the catalysts in NTP-driven catalytic CO2 hydrogenation. A kinetic study revealed that the NTP-catalysis has a lower activation energy (at ∼21 kJ mol−1) than that of the thermal catalysis (ca. 82 kJ mol−1), due to the alternative pathways enabled by NTP, which was confirmed by the comparative in situ diffuse reflectance infrared Fourier (DRIFTS) coupled with mass spectrometry (MS) characterisation of the catalytic systems.

In the past five decades, our knowledge in porous materials has been increased significantly, in particular, our understanding of how the porosity and chemical nature of porous materials influence their final properties and performances in heterogeneous catalysis. This chapter briefly reviews the current porous materials with industrial relevance, especially their sustainable aspects regarding synthesis, treatment, and catalytic application. Specific focuses are given to hierarchical zeolites (i.e., a class of zeolites with mesoporosity) and structured zeolites supported on macroscopic support catalysts (i.e., structured zeolites), which have the potential to enable the sustainable use of zeolites and zeolite-based catalysts for intensified catalytic transformations in industry. Detailed information on the recent development of these materials and on their real or potential uses is also discussed.

A systematic study of Ni supported on metal–organic frameworks (MOFs) catalyst (i.e., 15Ni/UiO‐66) for catalytic CO2 hydrogenation under nonthermal plasma (NTP) conditions was presented. The catalyst outperformed other catalysts based on conventional supports such as ZrO2, representing highest CO2 conversion and CH4 selectivity at about 85 and 99%, respectively. We found that the turnover frequency of the NTP catalysis system (1.8 ± 0.02 s−1) has a nearly two‐fold improvement compared with the thermal catalysis (1.0 ± 0.06 s−1). After 20 hr test, XPS and HRTEM characterizations confirmed the stability of the 15Ni/UiO‐66 catalyst in the NTP‐activated catalysis. The activation barrier for the NTP‐activated catalysis was calculated as ~32 kJ mol−1, being lower than the activation energy of the thermal catalysis (~70 kJ mol−1). In situ DRIFTS characterization confirmed the formation of multiple carbonates and formates on catalyst surface activated by NTP, surpassing the control catalysts (e.g., 15Ni/α‐Al2O3 and 15Ni/ZrO2).

Faujasite (FAU) Y zeolite assemblies with high mesoporosity (Sext. = 347 m2 g−1 and Vmeso = 0.52 cm3 g−1) were synthesised using sustainable and economic cellulose nanocrystals (CNCs) via a template-directed synthesis method, i.e. CNCs-Y. In comparison with the control zeolite catalysts of the conventioanl microporous Y and carbon nanotubes templated Y (CNTs-Y) zeolites, the resulting CNCs-Y demonstrated superior performance in catalytic dealkylation with excellent activity and longevity, as well as the anti-coking ability thanks to the exceptional mesoporous features of CNCs-Y zeolites. Thereby the method and relevent CNCs-Y mesoporous zeolites based on the sustainable CNCs presented here have significant implications for being developed further for improving the sustainability of relevent catalytic processes such as fluid catalytic cracking (FCC).

Plasma-assisted dry reforming of methane (DRM) was performed in a dielectric barrier discharge (DBD) reactor. The effect of different packing materials including ZrO2, UiO-67 MOF and PtNP@UiO-67 on plasma discharge was investigated, showing that ZrO2 suppressed the plasma generation while UiO-67 improves it due to its porous nature which favours the formation of filamentary microdischarges and surface discharges. The improved plasma discharge increased the conversion of CH4 and CO2 by about 18% and 10%, respectively, compared to the plasma-alone mode. In addition, the distribution of hydrocarbon products changed from dominant C2H6 in the plasma-alone mode to C2H2 and C2H4 in the UiO-67 promoted plasma-assisted DRM. The UiO-67 MOF was stable in plasma, showing no significant changes in its properties under different treatment times, discharge powers and gases. Pt nanoparticles (NPs) on UiO-67 improved plasma-assisted DRM, especially the selectivity due to the presence of surface reactions. Due to the dehydrogenation of hydrocarbons over Pt NPs, the selectivity to hydrocarbons decreased by 30%, compared to the UiO-67 packing. In situ diffuse reflectance infrared Fourier transformed spectroscopy (DRIFTS) was carried out to probe the surface reactions on PtNP@UiO-67 catalyst, showing the decomposition of surface formats to CO and C2H4 dehydrogenation over the metallic Pt. The PtNP@UiO-67 catalyst showed good reusability in the plasma-assisted DRM, and H2 production was improved by high CH4/CO2 molar ratio and low feed flow rate.

Excess crude glycerol derived as a by-product from biodiesel industry prompts the need to valorise glycerol to value-added chemicals. In this context, catalytic steam reforming of glycerol (SRG) was proposed as a promising and sustainable alternative for producing renewable hydrogen (H2). Herein, the development of nickel (Ni) supported on ceria-modified mesoporous γ-alumina (γ-Al2O3) catalysts and their applications in catalytic SRG (at 550–750 °C, atmospheric pressure and weight hourly space velocity, WHSV, of 44,122 ml·g−1·h−1 (STP)) is presented. Properties of the developed catalysts were characterised using many techniques. The findings show that ceria modification improved Ni dispersion on γ-Al2O3 catalyst support with highly active small Ni particles, which led to a remarkable catalytic performance with the total glycerol conversion (ca. 99%), glycerol conversion into gaseous products (ca. 77%) and H2 yield (ca. 62%). The formation rate for H2 production (14.4 × 10−5 mol·s−1·g−1, TOF (H2) = 3412 s−1) was significantly improved with the Ni@12Ce-Al2O3 catalyst, representing nearly a 2-fold increase compared with that of the conventional Ni@Al2O3 catalyst. In addition, the developed catalyst also exhibited comparatively high stability (for 12 h) and coke resistance ability.

Due to the superior performance in thermal conductivity and mechanical strength, the foam SiC-supported ZSM-5 catalyst is favorable in fixed bed methanol-to-propylene (MTP) reactions, where the temperature distribution and pressure drop are strictly controlled. However, its performance and service life in multiple reaction–regeneration cycles has not been proved yet. Both the activity and selectivity of the catalyst will be tested in six reaction–regeneration cycles in a fixed bed reactor. In addition, the properties of the catalyst during the fourth cycle were characterized by various techniques (scanning electron microscopy, Brunauer–Emmett–Teller, 27Al nuclear magnetic resonance). The results show that, as the reaction progresses, the catalyst continuously deposits carbon, and the local high temperature of carbon burning during regeneration leads to the removal of aluminum from the zeolite framework. Therefore, the catalyst life in one single process increases first and then decreases. At the same time...