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Zeolite nanosheets with excellent mass transfer are attractive, but their successful syntheses are normally resulted from a huge number of experiments. Here, we show the design of a small organic template for the synthesis of self-pillared pentasil (SPP) zeolite nanosheets from theoretical calculations in interaction energies between organic templates and pentasil zeolite skeletons. As expected, the SPP zeolite nanosheets with the thickness at 10-20 nm have been synthesized successfully. Characterizations show that the SPP zeolite nanosheets with about 90% MFI and 10% MEL structures have good crystallinity, the house-of-card morphology, large surface area, and fully four-coordinated aluminum species. More importantly, methanol-to-propylene tests show that the SPP zeolite nanosheets exhibit much higher propylene selectivity and longer reaction lifetime than conventional ZSM-5 zeolite. These results offer a good opportunity to develop highly efficient zeolite catalysts in the future.

The SSZ-39 zeolite is regarded as a promising small-pore zeolite for industrial applications due to its excellent catalytic properties and this review briefly summarizes the recent advances in the synthesis and application of the SSZ-39 zeolite.

An organotemplate-free synthesis of Al-rich ZSM-35 (Si/Al ratio at about 5) and ZSM-22 (Si/Al ratio at about 20) zeolites has been successfully shown with the addition of ZSM-57 zeolite seeds in the absence of organic templates.

Rapid synthesis of Si-rich (SiO

The metal-exchanged zeolites as catalysts have been widely applied in many catalytic reactions, but their syntheses are environmentally unfriendly due to the multiple steps such as ion-exchange for the formation of a large amount of wastes. Herein, we for the first time report a method for one-pot fabrication of metal-zeolite catalysts (M-SSZ-13, M-Beta, M-ZSM-5, and M-EU-1; M = Cu, Co, Ni) from a combination of solvent-free and sodium-free routes by mixing, grinding, and heating the raw materials of aluminosilicate gel, organic templates, and metal-amine complexes. As a typical example, Cu-SSZ-13 zeolite is successfully synthesized from heating the mixture of aluminosilicate gel, organic template, and Cu-amine complex. Catalytic tests in selective catalytic reduction of NOx with NH3 (NH3-SCR) show that the synthesized Cu-SSZ-13 zeolite before and after hydrothermal aging at 750 °C for 16 h are completely comparable with the commercial Cu-SSZ-13 zeolite from the conventional hydrothermal synthesis. Very interestingly, the method in this work has obvious advantages such as high yield, reduced pollutants, and simple process, which should be potentially important for practical applications of the metal-zeolites in the future.

In this work, we show for the first time that high-silica zeolites (MFI, TON, MTT, and *MRE) could be synthesized from a combined strategy of both zeolite seeding and alcohol filling in the absence of organic structure-directing agents (OSDAs). High-silica ZSM-5 zeolites with Si/Al ratios ranging from 38 to 240 (TF-Al-ZSM-5) could be synthesized via this route. The key to the success of this technique was the employment of an aluminosilicate precursor with a fully 4-coordinated aluminum species as the initial source, wherein the rearrangement and condensation of the silicate species, rather than the aluminate species, occurred during zeolite crystallization. In addition, heteroatoms, such as Fe and B, could be incorporated into the zeolite frameworks. Catalytic tests for the methanol-to-propylene (MTP) reaction exhibited good catalytic performance for TF-Al-ZSM-5, which was comparable to that of the aluminosilicate ZSM-5 zeolite synthesized with OSDAs. Hence, this method offers viable opportunities for the industrial production and catalytic application of high-silica zeolites in the future.

Fluoride-free synthesis of beta zeolite with enrichment of polymorph B is successfully achieved by using raw materials of solid silica gel, organic templates, sodium hydroxide, and zeolite seeds in the absence of any solvents.

Ionothermal synthesis has been widely used for the preparation of aluminophosphate-based molecular sieves, coordination polymers, metal-organic frameworks, and covalent organic frameworks. However, this method is still challenging for synthesis of silica-based zeolites. Herein, we show a generalized ionothermal route to synthesize silica-based zeolites with MTT, TON, ITW, and MFI structures in the presence of NH4F as a mineralizing agent and ionic liquid as a solvent and/or structure directing agent. The presence of a suitable amount of NH4F plays a key role for the successful synthesis of these silica-based zeolites. This methodology might open a pathway to ionthermally synthesize silica-based zeolites.

Currently, the synthesis of pure silica zeolites always requires the presence of organic structure-directing agents (OSDAs), which direct the assembly pathway and ultimately fill the pore space. A sustainable route is now reported for synthesizing pure silica zeolites in the absence of OSDAs from a combined strategy of zeolite seeding and alcohol filling, where the zeolite seeds direct crystallization of zeolite crystals from amorphous silica, while the alcohol is served as pore filling in the zeolites. Very importantly, the alcohol could be fully washed out from zeolite pores by water at room temperature, which completely avoids calcination at high temperature for removal of OSDAs in the synthesis of pure silica zeolites.

For the first time, SSZ-39 zeolite has been directly prepared using conventional colloidal silica and sodium aluminate instead of using FAU zeolite as the raw material in the alkaline media. The adjustment of the Si/Al ratios in the starting materials to the suitable values is a key factor to prepare the aluminosilicate SSZ-39 zeolite. Various characterizations (for instance, X-ray diffraction, scanning electron microscopy, nitrogen sorption, solid 27Al NMR, and NH3-temperature-programmed desorption) display that the aluminosilicate SSZ-39 zeolite owns high crystallinity, uniform cuboid morphology, large surface area, four-coordinated aluminum species, and strong acidic sites. Inductively coupled plasma analysis shows that the SiO2/Al2O3 ratios of the SSZ-39 products are ranged from 12.8 to 16.8. Considering the special framework of the SSZ-39 zeolite, the yield of this synthesis is not higher than 21.3%. Moreover, the catalytic performance of Cu-SSZ-39 catalyst synthesized from this route is excellent in the selective catalytic reduction of NO x with NH3 (NH3-SCR).

Photocatalytic synthesis of hydrogen peroxide (H2O2) from water and oxygen is an alternative route for clean energy storage and chemical synthesis, but still having problems with insufficient H2O2 productivity and solar-to-chemical energy conversion efficiency. Herein, we reported a hybrid catalyst of proton-form titania nanotube with carbon dot (HTNT-CD) that is highly efficient for the production of H2O2 under visible-light irradiation (λ > 420 nm, H2O2 productivity at 3.42 mmol gcat−1⋅h−1), outperforming the titania catalysts containing noble metals and the carbon nitride catalysts reported previously. Multiple studies demonstrate that the protons on the HTNT-CD are crucial for the production of H2O2 by efficiently accelerating the half reaction of molecular oxygen reduction to form H2O2, and effectively hindering H2O2 decomposition under the irradiation conditions. This HTNT-CD catalyst gives solar-to-H2O2 apparent energy conversion efficiency at 5.2%, which is even 4.9 times of that (1.06%) over the catalyst derived from commercial P25 and CDs. More importantly, the HTNT-CD is stable, giving high H2O2 productivity in the continuous recycle tests.

Developing sustainable routes for the synthesis of zeolites is still a vital and challenging task in zeolite scientific community. One of the typical examples is sustainable synthesis of aluminosilicate EU-1 zeolite, which is not very efficient and environmental-unfriendly under hydrothermal condition due to the use of a large amount of water as solvent. Herein, we report a sustainable synthesis route for aluminosilicate EU-1 zeolite without the use of solvent for the first time. The physicochemical properties of the obtained EU-1 zeolite are characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry-differential thermal analysis (TG-DTA), N2 sorption, inductively coupled plasma (ICP) analysis, and solid nuclear magnetic resonance (NMR), which show the product has high crystallinity, uniform morphology, large BET surface area, and four-coordinated aluminum species. Moreover, the impact of synthesis conditions is investigated in detail. The sustainable synthesis of aluminosilicate EU-1 zeolite under solvent-free

As one of the most important porous materials, zeolites with intricate micropores have been widely employed as catalysts for decades due to their large pore volume, high surface area, and good thermal and hydrothermal stabilities. Among them, ferrierite (FER) zeolite with a two-dimensional micropore structure is an excellent heterogeneous catalyst for isomerization, carbonylation, cracking, and so on. In the past years, considering the important industrial application of FER zeolite, great efforts have been made to improve the synthesis of FER zeolite and thus decrease the synthesis cost and enhance catalytic performance. In this review, we briefly summarize the advances in the synthesis of FER zeolite including the development of synthesis routes, the use of organic templates, organotemplate-free synthesis, the strategies of morphology control, and the creation of intra-crystalline mesopores. Furthermore, the synthesis of hetero-atomic FER zeolites such as Fe-FER and Ti-FER has been discussed.

The incorporation of metal heteroatoms into zeolites is an effective modification strategy for enhancing their catalytic performance. Herein, for the first time we report a generalized methodology for inserting metal heteroatoms (such as Sn, Fe, Zn, and Co) into the layered zeolite precursor RUB-36 via interlayer expansion by using the corresponding metal acetylacetate salt. Through this generalized methodology, Sn-JHP-1, Fe-JHP-1, Zn-JHP-1 and Co-JHP-1 zeolites could be successfully prepared by the reaction of RUB-36 and corresponding metal acetylacetate salt at 180 °C for 24 h in the presence of HCl solution. As a typical example, Sn-JHP-1 and calcined Sn-JHP-1 (Sn-JHP-2) zeolite is well characterized by the X-ray diffraction (XRD), diffuse reflectance ultraviolet-visible (UV-Vis), inductively coupled plasma (ICP), N2 sorption, temperature-programmed-desorption of ammonia (NH3-TPD) and X-ray photoelectron spectroscopy (XPS) techniques, which confirm the expansion of adjacent interlayers and thus the incorporation of isolated Sn sites within the zeolite structure. Notably, the obtained Sn-JHP-2 zeolite sample shows enhanced catalytic performance in the conversion of glucose to levulinic acid (LA) reaction.

Ultrathin nanosheets (6–8 nm) of aluminosilicate FER zeolites have been successfully synthesized using a sole small organic ammonium (N,N-diethyl-cis-2,6-dimethyl piperidinium, DMP). Catalytic tests on the skeletal isomerization of 1-butene to isobutene show that the FER nanosheets exhibit much higher conversion and selectivity than conventional FER zeolites.

Modern methodologies for synthesizing zeolites typically involve the employment of costly organic structure-directing agents. Herein, we report the design synthesis of aluminosilicate zeolite with ITE structure using an inexpensive nickel–amine complex (nickel–pentaethylenexamine) as a novel structure-directing agent. Characterizations including X-ray diffraction, scanning electron microscopy, N2 sorption isotherms, and 27Al magic-angle spinning NMR techniques show that the ITE zeolite has high crystallinity, perfect crystals, large surface area, and abundant aluminum species in the framework. More importantly, catalytic tests on the hydrogenation of CO2 into methane show that the Ni–ITE zeolite exhibits better catalytic performance than aluminosilicate-supported and silica-supported nickel catalysts. Obviously, the use of nickel–amine complex offers an alternative and facile way to synthesize aluminosilicate zeolites.

In this work, several efficient heterostructured nanocomposites with enhanced CO2 photoreduction activity were successfully constructed by anchoring carbon quantum dots onto TiO2 using a facile microwave assisted synthesis strategy. The carbon quantum dots obtained by microwave treatment of thiourea and citric acid acted as a sensitizer in the composites to enhance light absorption. The high-resolution transmission electron microscopy (HR-TEM) revealed that a closely integrated interface between carbon quantum dots and TiO2 nanosheets was formed in the heterostructured nanocomposites. Furthermore, the photogenerated charge transfer and separation in the heterogeneous nanocomposites were demonstrated to be significantly improved when compared with that in pristine TiO2. Consequently, a remarkable enhancement of photocatalytic activity evaluated for CO2 photoreduction under simulated solar light irradiation can be found in the nanocomposites. Maximum CH4 and CO yields of 0.769 and 1.153 μmol, respectively, have been obtained from the photoreduction after one hour irradiation without any noble metal loaded on photocatalyst. The amounts of CH4 and CO generated over nanocoposite are 7.79 and 7.61 times as high as those on pristine TiO2. This encouraging performance in CO2 photoreduction shows that these nanocomposites might be a prospective material in environmental protection and energy conversion.

2,6-methyl-N-methylpyridinium, as a novel organic template, is employed for the synthesis of RTH aluminosilicate zeolite with a SiO2/Al2O3 ratio of 17.6. The amount of 2,6-methyl-N-methylpyridinium template, the Na2O/SiO2 ratio, the SiO2/Al2O3 ratio, and the H2O/SiO2 ratio in the starting gel significantly influence the crystallization of RTH zeolite. Several analytical methods such as XRD, SEM, N2 sorption, TG-DTA, DRIFT and NMR were employed for the characterisation of the obtained RTH zeolites and to understand the crystallization process with the new template. Very interestingly, the crystallization of RTH zeolite with the new template takes a very short time (12 h at 130 °C and 50 min at 240 °C) compared with conventional RTH zeolite synthesis reported in the literature (72 h at 130 °C). Theoretical calculations show that this novel organic template has lower interaction energies for zeolite cage space filling than those of the organic templates previously reported in the literature, which lead to stronger structural directing. Kinetic results show that the activation energy of this novel organic template is much lower than that of the traditional one. Catalytic tests show that copper exchanged RTH zeolite (Cu-RTH) exhibits good catalytic properties in the NH3-SCR reaction and the H-RTH zeolite catalyst has excellent selectivities for ethylene and propylene in MTO reactions.

Exploring appropriate supports is a key step to prepare efficient water-gas shift (WGS) catalysts. In this sense, supports with some oxygen vacancies are preferable, but there have been no efficient methods to obtain abundant stable surface oxygen vacancies. Here, a black TiO2−x support rich in stable surface oxygen vacancies was prepared by hydrogen-etching technology. More impressively, compared with the gold catalyst supported on traditional white TiO2, the gold catalyst supported on black TiO2−x has been proven to be an efficient and stable WGS catalyst. According to the in-depth characterization of its structural properties, the disordered layer and abundant stable surface oxygen vacancies of the black TiO2−x support lead to higher microstrain and more metallic Au0 species, respectively, which are all in favor of higher WGS catalytic activities. Furthermore, we successfully linked the WGS thermocatalytic activities with the optoelectronic properties, and then tried to understand the WGS pathway from the view of an electron flow process. Hereinto, the Ohmic barrier has been decreased because of the narrowed forbidden band gap, which improves the transmission efficiency of “hot-electron flow”. Meanwhile, the abundant surface oxygen vacancies function as electron traps, thus promoting the flow of “hot-electrons” and reduction reaction of H2O. As a consequence, the WGS catalytic activity is enhanced. The involved hydrogen-etching method resulting in abundant stable surface oxygen vacancies can be extended to other supported catalysts for WGS reaction or other thermocatalytic reactions.

We show that a nickel-amine complex (nickel-diethylenetriamine, Ni-DETA) is an efficient organic template for the one-pot synthesis of Ni-SSZ-13 zeolite. The effects of the reaction compositions, including the molar ratios of SiO2/Al2O3, H2O/Al2O3, Ni-DETA/Al2O3, and Na2O/Al2O3, on the synthesis of the pure product were investigated using different temperatures and synthesis times. Physicochemical characterizations, including XRD, SEM, and 27Al NMR, show that the zeolitic product has good crystallinity, uniform crystals, and contains a tetrahedral Al3+ species. The N2 sorption isotherms, TG–DTA curves, IR spectra, and UV–Vis spectra show that Ni-DETA acts as a template in the product obtained. Interestingly, Ni-SSZ-13 zeolite is obtained by the conversion of Ni-Y zeolite produced in the crystallization process.

Development of the sustainable routes for synthesis of ITQ-family zeolites is very important because of their unique structures and excellent catalytic and adsorptive properties. The burden of costly raw materials and low efficiency of synthesis put a strong challenge for their widespread commercial application. Here, we show an alternative and simple route for synthesis of ITQ-12, ITQ-13, and ITQ-17 zeolites using commercially available organic templates by a facile grinding process of anhydrous starting raw solids, followed by heating at 140—180 °C. Compared with the conventional hydrothermal synthesis, this approach has obvious advantages such as employment of low-cost organic templates with very high effectiveness, high yield of zeolite products, short crystallization time, and relatively simple procedures. This methodology might open a pathway to synthesize ITQ zeolites with more sustainable manner.

Preparation of aluminosilicate ferrierite (FER) zeolite nanosheets with controllable thickness in the presence of a sole organic ammonium is attractive, but still challenging. In this report, with the employment of N,N-diethyl-cis-2,6-dimethylpiperidinium (DMP) as both a structure directing agent and crystal growth inhibitor, aluminosilicate FER zeolite nanosheets, with a variety of crystal thicknesses, ranging from 6 to 200 nm, are successfully synthesized under hydrothermal conditions. Very interestingly, the amount of DMP in the starting gel is the key factor for crystal thickness control of aluminosilicate FER zeolite nanosheets. The obtained FER products, with different thicknesses, are well characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), N2 sorption, thermogravimetric analysis (TG), inductively coupled plasma (ICP), and magic angle spinning nuclear magnetic resonance (MAS NMR) techniques. This simple strategy might provide a novel avenue for the synthesis of other zeolite nanosheets with controllable thickness.

Aluminosilicate SSZ-39 zeolite shows the excellent catalytic performance in selective catalytic reduction of NOx with NH3 (NH3-SCR) reaction, but their synthesis is still not efficient due to the use of a large amount of water as a solvent under hydrothermal condition. Herein, for the first time, we report a solvent-free synthesis of aluminosilicate SSZ-39 zeolite without addition of water in the presence of N,N-dimethyl-3,5-dimethylpiperidine (DMDMP) cation as an organic structure-directing agent. Various characterizations, including powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry-differential thermal analysis (TG-DTA), N2 sorption, inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis, solid nuclear magnetic resonance (NMR) and NH3-temperature-programmed desorption (NH3-TPD), show that the aluminosilicate SSZ-39 zeolite displays high crystallinity, uniform sheet-like morphology, large surface area, four-coordinated aluminum species, strong acidic sites and excellent hydrothermal stability. Compared with the conventional synthesis for aluminosilicate SSZ-39 zeolite, the solvent-free synthesis of aluminosilicate SSZ-39 zeolite has the obvious advantages such as high product yield, simple synthesis procedures, and the reduction of pollutants. More importantly, the copper-exchanged aluminosilicate SSZ-39 zeolite shows the good catalytic performance in NH3-SCR reaction, which is fully comparable with that of the Cu-SSZ-39 zeolite synthesized under hydrothermal condition from the reported literature.

The nanocomposite preparation procedure plays an important role in achieving a well-established heterostructured junction, and hence, an optimized photocatalytic activity. In this study, a series of g-C3N4/ZnO nanocomposites were prepared through two distinct procedures of a low-cost, environmentally-friendly, in-situ fabrication process, with urea and zinc acetate being the only precursor materials. The physicochemical properties of synthesized g-C3N4/ZnO composites were mainly characterized by XRD, UV–VIS diffuse reflectance spectroscopy (DRS), N2 adsorption-desorption, FTIR, TEM, and SEM. These nanocomposites’ photocatalytic properties were evaluated in methylene blue (MB) dye photodecomposition under UV and sunlight irradiation. Interestingly, compared with ZnO nanorods, g-C3N4/ZnO nanocomposites (x:1, obtained from urea and ZnO nanorods) exhibited weak photocatalytic activity likely due to a “shading effect”, while nanocomposites (x:1 CN, made from g-C3N4 and zinc acetate) showed enhanced photocatalytic activity that can be ascribed to the effective establishment of heterojunctions. A kinetics study showed that a maximum reaction rate constant of 0.1862 min-1 can be achieved under solar light illumination, which is two times higher than that of bare ZnO nanorods. The photocatalytic mechanism was revealed by determining reactive species through adding a series of scavengers. It suggested that reactive ●O2− and h+ radicals played a major role in promoting dye photodegradation.

The conversion of bioethanol into valuable products is an important area in the conversion of biomass. We demonstrate the successful synthesis of bimetallic gold-palladium (Au-Pd) nanoparticles encapsulated within S-1 zeolite crystals (AuPd@S-1) by a solvent-free strategy. This strategy allows highly efficient use of the noble metals, with more than 96 % of the gold and palladium being loaded into the final samples. Electron microscopy characterization and investigations with probe molecules confirm that the Au-Pd nanoparticles are encapsulated inside the S-1 crystals. The AuPd@S-1 catalyst is very active for the aerobic oxidation of bioethanol, giving 100 % conversion and 99 % selectivity to acetic acid. Even in the presence of 90 % water, the catalyst still gives a conversion higher than 80 % and a selectivity of 95 %. More importantly, the AuPd@S-1 catalyst exhibits excellent stability in the oxidation of bioethanol. These features are important for future practical applications of the AuPd@S-1 catalyst.

We report a solvent-free synthesis of all silica Beta zeolite using a cheap organic template of tetraethylammonium bromide (TEABr). The method includes mixing, grinding and heating solid raw material in the absence of water solvent but the presence of zeolite seeds. The absence of water solvent significantly improves the efficiency of synthesis, while the addition of seeds remarkably enhances the crystallization rate. In addition, the use of a cheap organic template of TEABr greatly decreases the synthesis cost. The effects of the reaction compositions, including the molar ratios of NH4F/SiO2, TEABr/SiO2, and mass ratios of seeds to the silica, on the synthesis of the pure product were investigated using different temperature. Physicochemical characterizations, including XRD, SEM, TG and N2 sorption, show that the zeolitic product has good crystallinity, uniform crystals, and high surface area.

Structurally interlocked multi-armed carbon with a highly extended surface may be conveniently prepared by the deterministic growth of ZIF-8 on ZnO multiarms and the subsequent pyrolysis, which exhibits excellent stability and methanol corrosion resistance for oxygen reduction application.

The development of highly-efficient catalysts for conversion of glucose and fructose to 5-hydroxymethylfurfural (HMF) is of great importance. In this work, theoretical simulations form the basis for rational design and synthesis of a superhydrophobic mesoporous acid, that can completely prevent HMF hydration, giving HMF as sole product from full conversion of fructose. Interestingly, the combined superhydrophobic solid acid and superhydrophilic solid base catalysts are very efficient for one-pot conversion of glucose to HMF, giving a yield as high as 95.4 %. The excellent catalytic data in the conversion of glucose to HMF is attributed to the unique wettabilities of the solid acid and base catalysts.

Homogeneous chiral catalysts usually show higher catalytic activities than corresponding heterogeneous chiral catalysts, because of their easy interaction between catalytically active sites with reactant molecules. We demonstrate here superhydrophobic, chiral, and mesoporous catalysts (TsDPEN-Ru) synthesized from copolymerization of N-p-styrenesulfonyl-1,2-diphenylethylenediamine (V-TsDPEN) with divinylbenzene and loading of Ru species exhibiting much higher activities in asymmetric transfer hydrogenation (ATH) of ketones in aqueous solution than corresponding homogeneous chiral catalyst. This phenomenon is strongly related to the unique features of high enrichment for the reactants in superhydrophobic TsDPEN-Ru catalysts due to their good wettability, as well as easy transfer of product from the catalyst into water phase. These features open a door for design and developing a wide variety of chiral catalysts for asymmetric catalysis.

Sulfated porous carbon (PC-SO 3 H) catalyst was successfully synthesized from one-pot treatment of porous polydivinylbenzene in H 2 SO 4 at 250 °C, which exhibited very good catalytic performances in the production of 5-hydroxymethylfurfural from fructose.

Co-salen functionalized on graphene with an average pore size of 27.7 nm as a heterogeneous catalyst exhibited good catalytic activity and recyclability in cyclohexene oxidation.

Reported in this paper is a solvothermal synthesis of highly porous polydivinylbenzene. The nanoporous structures of the resultant polymers could be modulated from macro/mesoporosity to meso/microporosity by simply changing the amount of acetone solvent in the synthesis. A micro-phase separation during the solvothermal process was found to be the key factor for this transition in porous structures. The hierarchically porous polymers prepared here were characterized by N 2 physi-sorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and contact angle testing. Experimental results show that these nanoporous polymers have large BET surface areas (up to 420 m 2 /g), large pore volumes (up to 1.73 cm 3 /g), and superhydrophobicity due to their highly porous structures, which make these nanoporous materials an excellent candidate for selective removal of toxic volatile organic compounds (VOCs). In the adsorption tests, the nanoporous polymers show outstanding adsorptive capacity and very high selectivity to organic compounds, giving a great potential for indoor VOCs removal.

Magnetically active, thermally stable, and ordered mesoporous resin (MOMR-200) and carbon (MOMC-200) monoliths were prepared by one-pot hydrothermal synthesis from resol, copolymer surfactant, and iron cations at high-temperature (200 ∘C), followed by calcination at 360 ∘C and carbonization at 600 ∘C. X-ray diffraction results show that both MOMR-200 and MOMC-200 have ordered hexagonal mesoporous symmetry, and N2 isotherms indicate that these samples have uniform mesopores (3.71, 3.45 nm), high surface area (328, 621 m2/g) and large pore volume (0.31, 0.43 cm3/g). Transmission electron microscopy shows that iron nanoparticles, which are superparamagnetic in nature, are dispersed in the network. More importantly, the high temperature (200 ∘C) products exhibit much better stability than the samples synthesized at low temperature (100 ∘C). Interestingly, MOMC-200 has higher adsorption capacity for organic dyes when compared with commercial adsorbents (activated carbon and macroporous resin: XAD-4). Combining the advantages such as magnetically active, thermally stable networks, ordered and open mesopores, high surface area, large pore volume, adsorption of pollutants in water and desorption in ethanol solvent, MOMC-200 is potentially important for water treatments.

Magnetically active and SO3H-functionalized ordered mesoporous resin and carbon (MOMR-SO3H, MOMC-SO3H) were successfully prepared by high-temperature hydrothermal synthesis from resol, copolymer surfactant, and iron cations at 180 °C, followed by sulfonation from sulfuric acid fuming. X-ray diffraction patterns show that MOMR-SO3H and MOMC-SO3H have ordered hexagonal mesoporous symmetry. N2 isotherms indicate that these samples have uniform and opened mesopores, high surface areas (335–591 m2/g), and large pore volumes (0.34–0.35 cm3/g). Transmission electron microscopy shows that iron nanoparticles, which are superparamagnetic in nature, are highly dispersed in MOMC-SO3H sample. Catalytic tests show that MOMC-SO3H is highly active and excellently recyclable in esterification of acetic acid with butanol, esterification of acetic acid with cyclohexanol, and condensation of benzaldehyde with ethylene glycol. More interestingly, MOMC-SO3H catalyst is magnetically active, showing potential applications for separating catalysts by a magnetic field in the future.

Small-pore zeolite levyne has been successfully synthesized following an organotemplate-free route using RUB-50 zeolite as seeds with the aid of a small amount of alcohols. Physicochemical characterization with a combination of techniques including XRD, N 2 adsorption, FE-SEM, 27 Al and 29 Si NMR, and TPD-NH 3 shows that the zeolitic product from this seed-directed organotemplate-free synthesis approach (designated as LEV-SDS) has good crystallinity, high surface area, uniform crystals, tetrahedral Al 3+ species, and abundant acidic sites. It is also found that alcohols play an important role in preparation of LEV-SDS zeolite by inhibiting the formation of MOR zeolite. Catalytic tests for the conversion of methanol-to-olefins (MTO) show that H-form of LEV-SDS zeolite exhibits good conversion of methanol and high selectivities for ethylene and propylene, which could be potentially important for using LEV-SDS zeolite as a catalyst in MTO reaction.

Novel excellent hydrophobic- mesoporous- polymer-based solid acid catalysts have been successfully synthesized by copolymerization of divinylbenzene (DVB) with sodium p-styrene sulfonate (H-PDVB-x-SO3H's) under solvothermal conditions. N2 isotherms and TEM images showed that H-PDVB-x-SO3H's have high BET surface areas, large pore volumes, and abundant mesoporosity; CHNS element analysis and acid–base titration technology showed that H-PDVB-x-SO3H's have adjustable sulfur contents (0.31–2.36 mmol/g) and acidic concentrations (0.26–1.86 mmol/g); TG curves showed that H-PDVB-x-SO3H's exhibited much higher stability of the active site (372 °C) than that of the acidic resin of Amberlyst 15 (312 °C); contact angle and water adsorption tests showed that H-PDVB-x-SO3H's exhibited excellent hydrophobic properties. Catalytic tests in esterification of acetic acid with cyclohexanol, esterification of acetic acid with 1-butanol, and condensation of benzaldehyde with ethylene glycol showed that H-PDVB-x-SO3H's were mo...