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cis-Pinane was efficient and selective prepared through the hydrogenation of α-pinene base on Ru nanoparticles stabilized by amine-functionalized magnetite nanoparticles (Fe3O4/NH2/Ru). The effects o`f changing carbon chain length on amine-functionalized catalyst formation have also been investigated. The characterization results showed that Ru nanoparticles could be efficient loaded by 1, 6-hexanediamine functionalized magnetite nanoparticles. At the same time, Fe3O4/1, 6-hexanediamine/Ru had good superparamagnetic properties and that the introduction of the amine-functionalized improved the monodispersity, morphological regularity and size uniformity of the Ru nanoparticles. The Fe3O4/1, 6-hexanediamine/Ru catalyst was completely recoverable with the simple application of an external magnetic field and the catalytic efficiency showed no obvious loss for the hydrogenation of α-pinene even after ten repeated cycles.

An economic method for the synthesis of crystalline mesoporous sieves and the self-oxidation of alkali lignin (INDULIN AT) to aromatic acids is reported herein. Crystalline mesoporous molecular sieves ILM-Al have been prepared in strongly acidic ionic liquid (IL) media and used as catalysts for the self-oxidation of alkali lignin to aromatic acids. In the preparation of the new type of mesoporous molecular sieves, the imidazolium-based acidic functional IL system served as both solvent and structure-directing agent. The ILM-Al exhibited higher catalytic performance and selectivity for aromatic acids in the self-oxidation of lignin than in that of fossil fuels, and the main products were homoveratric acid and homovanillic acid. The catalyst could be recycled and reused with negligible loss in activity over five cycles, and the IL could also be recycled for further use. Moreover, Zr and Sn were also successfully incorporated into the framework of ordered crystalline mesoporous materials by the same simple m...

Hydrolysis of poly(3-hydroxybutyrate) (PHB) was studied using acidic functionalized ionic liquid 1-methyl-3-(3-sulfopropyl)-immidazolium hydrogen sulfate ([HSO 3 -pmim][HSO 4 ]) as catalyst. The influences of experimental parameters, such as reaction temperature, reaction time, the amount of catalyst and mole ratio of water to PHB were investigated. Under the conditions of reaction temperature 160 °C, reaction time 4.0 h, m ([HSO 3 -pmim][HSO 4 ]): m (PHB) = 0.06:1 and n (H 2 O): n (PHB) = 7:1, the conversion of PHB was over 98%. The ionic liquid could be reused up to 6 times without apparent decrease in the conversion of PHB. In addition, the kinetics of the reaction was investigated, the result indicated that hydrolysis of PHB in [HSO 3 -pmim][HSO 4 ] was a first-order kinetic reaction and the activation energy was 171.1 kJ/mol.

A magnetic Ru/Fe3O4@C catalyst was prepared by loading Ru nanoparticles on a controller carbon layer. The characterization results showed that Ru/Fe3O4@C with the core-shell structured microspheres had good superparamagnetic properties and that the introduction of the controlled carbon layer adsorbent improved the morphological regularity, monodispersity and size uniformity of the Ru nanoparticles. The Ru/Fe3O4@C catalyst demonstrated a high catalytic activity towards the hydrogenation of α-pinene to form cis-pinane. The conversion of α-pinene was 99.3% and the selectivity for cis-pinane reached 98.2% at 160 °C for 2 h. The Ru/Fe3O4@C catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Ru/Fe3O4@C had a good reusability. After being reused 10 times, the α-pinene conversion and the cis-pinane selectivity decreased to 97.6% and 97.1%, respectively.

A new type of Pd@mSiO

Conventional acidic catalysts for isobutane and isobutene alkylation exhibit low alkylate selectivity. Herein, we employed an acidic deep eutectic solvent, consisting of trifluoromethanesulfonic acid and taurine, in polyethylene glycol as the catalyst. Its high conversion rate and selectivity, as well as recyclability, make it suitable for alkylate gasoline preparation.

This article reports an efficient synthesis of triarylmethanes and tetraarylmethanes from chlorohydrocarbons with miscellaneous nucleophiles in fluorinated alcohols, featuring metal-free, wide substrate scope, excellent functional group tolerance, and mild reaction conditions.

Polycarbonate (PC) is a very versatile material widely used in industry, agriculture and packaging, etc. The global production of PC generates several million tons of non-biodegradable wastes. In this work, chemical recycling of bisphenol A (BPA) from the PC methanolysis was explored, by using Mg/Al layered double hydroxides (LDHs) and their corresponding layered double oxides (LDOs) as heterogeneous catalysts. Mg/Al-LDHs with different molar ratios were prepared, and their hydrotalcite structures were confirmed by powder X-ray diffraction (XRD). Compared with Mg/Al-LDHs, Mg/Al-LDOs exhibited better catalytic activity for the PC methanolysis. Using Mg3Al-LDO as a catalyst, the PC conversion was 100% and the BPA yield exceeded 98% at 110 °C and 1.0 h. Namely, this method not only significantly reduces the reaction temperature, but also shortens the reaction time, and the solid catalyst Mg3Al-LDO can be easily separated and reused after calcinations again. The effects of experimental parameters on the PC conversion and the BPA yield were investigated. Moreover, the mechanism was described by infrared spectroscopy (IR), gel permeation chromatography (GPC), and scanning electron microscope (SEM). The kinetics of PC methanolysis was also studied, and the results indicated that this process is a pseudo-first-order reaction with an activation energy of 92.41 kJ/mol.

The sandwich construction of chitosan (CS)/reduced graphene oxide (rGO) composite was synthesized through microwave-assisted hydrothermal method without further carbonization or activation process (CRG). CS homogeneous attached between the rGO slice sheet and improve the dispersion of CRG effectively, which can increase its specific surface area with hierarchical porous structure. Dehydration condensation occurred between CS and rGO, forming NHCO groups that can promote the wettability and conductivity of the composites. CRG exhibited improved degree of order and reduced graphitization defect, N-5 and OI groups were the dominant nitrogen and oxygen-containing groups. When used as additive-free electrode, CRG exhibited a high specific capacitance of 274 F g-1 at the current density of 0.5 A g-1 with good rate performance in a three-electrode system using 1 M H2SO4 electrolyte. Solid-state supercapacitor device was assembled with CRG electrode and lignin hydrogel electrolytes, high gravimetric energy densities of 8.4 Wh kg-1 at the power density of 50 W kg-1 was achieved.

Mordenite molecular sieves were employed for the isomerization of α-pinene to produce limonene and camphene. To decrease diffusion resistance of α-pinene molecules, nanocrystalline cellulose (NCC) was employed as the mesoporous filler to prepare hierarchical mordenite within 6 h under microwave radiation. NCC crystals present as a rod-like morphology twining around crystals and interact with Al(OH)xOy and Si(OH)xOy species. Stronger interaction with Al(OH)xOy species inhibits the incorporation of aluminum into zeolitic framework. The acidity decreases due to a lower surface Si/Al ratio. Besides creating mesopores and macropores, NCC inhibits the growth or assembly of crystals in the short transverse direction of particles. Compared to mordenite without NCC, conversion increases by ∼50 % and the total yields of camphene and limonene are ∼52 % using mordenite catalysts with NCC. It indicates that macro/mesopores enhance the diffusion of α-pinene in mordenites, increase the accessibility of α-pinene with acid sites. After 5-times cycle tests, the conversion decreases from 63 % to 43 % due to the destruction of zeolitic structure during thermal treatment. In this study, a green synthesis route templated with NCC and green application in isomerization of α-pinene are proposed. These results are important for the synthesis of zeolites using biomass templates rapidly for biomass conversion process.

New mesoporous molecular sieves MMS-11, MMP-12, MNS-16, MNP-10, and MNC-13 were synthesized successfully using zeolite β as a silica–alumina source and different ionic liquids as templates. The structure and catalytic activity of the mesoporous molecular sieves as heterogeneous catalysts for the cracking of rubber seed oil (RSO) were studied in detail. MNC-13 exhibited excellent catalytic performance for the cracking of RSO, and the cracked oil had a chemical composition and properties similar to those of diesel-based fuels. Furthermore, the catalyst MNC-13 is of such outstanding stability that it retains high activity even after being used five times. Therefore, this research provides a new type of catalytic result for the same type of high-temperature cracking reaction.

Ce 3 + (La 3 + or Sm 3 + )~β/Al-MCM-41 molecular sieves were synthesized by impregnation and used to catalyze the esterification of oleic acid with short chain alcohols, such as methanol, ethanol, isopropanol, and isobutanol, to obtain biodiesel. Ce 3 + (La 3 + or Sm 3 + )~β/Al-MCM-41 was found to exhibit excellent catalytic activity and stability. The effect of rare earth elements on the acidity of catalysts was examined in detail by NH 3 -TPD and Py-FTIR. The optimum conditions for the esterification of oleic acid with methanol were determined. Moreover, the kinetics of the esterification showed that the average reaction order (n) was 1.92, with an activation energy of 51.46 kJ/mol.

Well-dispersed Pd particles supported on ordered mesoporous SBA-15 were synthesized by the incipient wetness impregnation of SBA-15 with PdCl2 as precursor. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption–desorption isotherms, inductively couple plasma atomic emission spectrometry (ICP-AES), and there was revealed an excellent dispersion of Pd nanoparticles in the mesoporous SBA-15 channels. Furthermore, Pd/SBA-15 mesoporous material was used as catalyst for hydrogenation of rosin and exhibited a highly catalytic activity and reusability at least after five recycles.

Mesoporous BaO-SBA-15 was directly synthesized in hydrothermal system, and then K2O/BaO-SBA-15 materials were synthesized by impregnating BaO-SBA-15 in different concentration KNO3 aqueous solution. The obtained materials were characterized by XRD, FT-IR, N2 adsorption/desorption and CO2-TPD. The results indicated that K2O/BaO-SBA-15 was of typical mesoporous structure and the long range order, and the introduction of K species improved the basicity of mesoporous material. The synthesized mesoporous materials were used as catalysts in the degradation of polystyrene (PS) and among them, 9 % K2O/BaO-SBA-15 exhibited the highest catalytic performance. Under the optimum conditions, the conversion of PS was 95.8 wt.% and the yield of styrene monomer could reach 85.0 wt.%. Furthermore, the stability of catalyst was investigated. The results showed that the catalyst was of excellent catalytic stability, there were less decreases in PS conversion and liquid product yield after six successive cycles of the catalyst.

Poly (3-hydroxybutyrate) (PHB) from an industrial manufacturer was depolymerized by methanol in the presence of acidic functionalized ionic liquids (ILs). It was demonstrated that 1-methyl-3-(3-sulfopropyl)-immidazolium hydrogen sulfate ([HSO 3 -pmim][HSO 4 ]) exhibited higher catalytic activity than other acidic functionalized ILs and traditional acids such as H 2 SO 4 and H 3 PO 4 . The main product of methanolysis was confirmed to be methyl 3-hydroxybutyrate monomer by FT-IR and 1 H NMR. The influences of experimental parameters, such as the amount of catalyst, reaction temperature, methanolysis time, and dosage of methanol on the conversion of PHB and yield of methyl 3-hydroxybutyrate were investigated. The results showed that the reaction temperature was a critical factor for depolymerization of PHB. Under the optimum conditions of n(CH 3 OH):n(PHB) = 5:1, m(IL):m(PHB) = 0.03:1, reaction temperature 140 °C and time 3 h, the conversion of PHB and the yield of product were over 90% and 83%, respectively. The IL could be reused up to 6 times without apparent decrease in the conversion of PHB and yield of product. Kinetics of the reaction was also investigated, it was indicated that methanolysis of PHB catalyzed by acidic functionalized [HSO 3 -pmim][HSO 4 ] was a first-order kinetic reaction with an activation energy of 16.02 kJ/mol. In addition, a detailed reaction mechanism of the methanolysis was proposed.

A highly efficient extractive desulfurization (EDS) system with polyether-based ionic liquids (ILs) as extractants has been developed. The polyether ILs, with two PEG chains and a benzyl group, exhibit very high affinities for sulfur compounds, in particular, for benzothiophenes and phenyl sulfides. These exceptional affinities are due to various interactions between the IL and sulfur compounds, which include electrostatic effects, hydrogen bonding, π–π interactions, and so on. The extraction equilibrium can be achieved within a few minutes near room temperature. The desulfurization rates of the refractory sulfur compounds, viz. benzothiophene (BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT), in model gasoline can reach 84.7%, 91.4%, and 81.0%, respectively. For multiple extractions of real gasolines, within four extraction cycles, the desulfurization rate of gasoline 93 # was nearly 100%, while the desulfurization rates of gasoline 90 # and light hydrocarbon gasoline reached 88.0% and 91.0%, respectively. Furthermore, the polyether IL stabilized by NaCl exhibited remarkable recyclability. The addition of NaCl into the IL minimized the loss of the extractant, making it negligible. After recycling the IL over 64 extraction cycles, the desulfurization rate was reduced by only a small amount and the mass loss of the IL was also very low (6.1%).

In the present study, some different amino acid ionic liquids(ILs) were designed in order to find new solvent which is of excellent solubility and poor degradation for chitosan. The designed ILs contain different amino acid cations and organic acid anions: amino acids cations included [Gly], [Pro], [Thr] and [Ser]; organic acids anions included [HCOOH], [CH 3 COOH], [CH 3 CH 2 COOH], [CH 2 aCHCOOH] and [CH 2 aC(CH 3 )COOH]. At the same time we used chemical software to construct the original structure of three excellent-dissolving ILs which were selected from the amino acid ILs we prepared, and the calculation results of chemical software showed [Thr][CH 3 CH 2 COO] that of E HOMO and E LUMO are −0.17699 and −0.02997 which was the easiest to form hydrogen bond with chitosan and caused the dissolution of chitosan. The present work could guide us to design more new solvent to dissolve chitosan, which can enlarge the usage range of chitosan.

A series of heteropoly acid bisalts of N-octyl ethoxylated octadecylamine with high acid strength and excellent emulsifying capacity have been prepared via the partial replacement of protons in neat phosphotungstic acid. These ionic liquids exhibit good activity and selectivity in the hydration of α-pinene, even in the absence of a co-catalyst such as chloroacetic acid. The “excellent emulsifying capacity at the reaction temperature and the liquid–liquid separation at room temperature” for the obtained organic heteropolyacid bisalts catalysts enable their easy recovery and reusability, as demonstrated by a six-run recycling test.

Rosin hydrogenation using polyvinylpyrrolidone (PVP)-stabilized Pd colloidal nanoparticles as catalyst in an aqueous/organic biphasic system was investigated. The influence of preparation methods on the size of Pd nanoparticles for hydrogenation of rosin was marked. Compared with traditional catalysts Pd/C and Raney-Ni, PVP-stabilized Pd colloidal nanoparticles showed excellent catalytic activity and promoted formation of the product tetrahydroabietic acid (THAA). More than 93 % rosin was hydrogenated, and the mass fraction of THAA was 54.2 % when the reaction was carried out at 160 °C for 4 h. It was also found that PVP-stabilized Pd colloidal nanoparticles exhibited good reusability for hydrogenation, with no obvious decrease in catalytic performance when reused six times.

Ru nanoparticles were prepared using polyoxyethylene–polyoxypropylene–polyoxyethylene triblock copolymer (F127, Mw: 13,000) micelles as stabilizers. The F127-Ru micellar catalyst was used in the hydrogenation of α-pinene to cis-pinane. Under very mild conditions, the conversion of α-pinene was 99.9 %, and selectivity for cis-pinane reached 99.0 %. The isolated catalyst phase could be reused six times with almost unchanged catalytic activity and selectivity. The improvement in conversion and selectivity was attributed to the formation of micellar microreactors, with the water insoluble substrate solubilized in the hydrophobic core of the micelles. This method offers an effective pathway for the production of a high value-added product from turpentine, and provides a reference for the catalytic hydrogenation of other hydrophobic natural products.

(3-Aminopropyl)-triethoxysilane (APTS) and (3-mercaptopropyl)-trimethoxysilane (MPTS) grafted SiO2-coated iron oxide (Fe3O4@SiO2) magnetic supports were prepared. Various noble metal nanoparticles such as Ru, Pt, Rh and Pd were directly grown on the surfaces of the magnetic supports with ultrasmall and nearly monodisperse sizes, especially the APTS grafted Fe3O4@SiO2 (Fe3O4@SiO2/APTS) nanospheres. The Fe3O4@SiO2/APTS/Ru catalyst demonstrated a high catalytic activity towards the hydrogenation of α-pinene to form cis-pinane. The conversion of α-pinene was 99.1% and the selectivity for cis-pinane reached 97.6% at 120 °C after 4 h. The Fe3O4@SiO2/APTS/Ru catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Fe3O4@SiO2/APTS/Ru had good reusability. After being reused eight times, the α-pinene conversion and the cis-pinane selectivity also can reach 97.8% and 96.9%, respectively.

D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS-1000) stabilized Ru(0) nanoparticles were prepared and characterized. These nanoparticles were employed to selectively hydrogenate α-pinene to cis-pinane. With a small amount of Na2CO3 present, reaction rates could be increased significantly, and the reaction medium could be readily recycled. TEM, CLSM, IR and leaching experiments were employed to quantify the advantages of the catalytic system. The procedure is environmentally friendly. It offers a reference for the catalytic hydrogenation of other hydrophobic natural products.

β/Al-MCM-41 molecular sieve was synthesized and used to catalyze the esterification of oleic acid with short chain alcohols such as methanol, ethanol, isopropanol and isobutanol to obtain biodiesel. The results indicated that β/Al-MCM-41 exhibited the excellent catalytic activity and stability, which was obviously superior to traditional Al-MCM-41. The relationship between acidity and catalytic activity was in detail examined by NH3-TPD and Py-FTIR. Moreover, the kinetics of esterification of oleic acid with methanol showed that the average reaction order n was 1.97 and that activation energy was 50.01 kJ/mol.

Montmorillonite (MMT) was used as the carrier for synthesis of FeOOH and FeOOH/ZnO nano-material. FeOOH and FeOOH/ZnO were synthesized by the aqueous solutions of Fe(NO 3 ) 3 –HNO 3 and Zn(NO 3 ) 2 –NaOH/Fe(NO 3 ) 3 –HNO 3 with the carrier of montmorillonite respectively. Transmission electron-microscopy (TEM) and X-ray diffraction (XRD) were used to study the morphology form and structure of the nano-materials. TEM was also used to demonstrate that FeOOH/ZnO can be formed with the appropriate interface. According to UV–vis absorption spectra, FeOOH/ZnO has a better response to visible light than FeOOH and ZnO, which indicates there is some coupling effect between FeOOH and ZnO. Pentachlorophenol (PCP) was used as a representative organic pollutant to evaluate the photo-catalytic efficiency of the FeOOH/ZnO and FeOOH catalysts in visible light ( λ > 400 nm). The photo-catalytic efficiency of FeOOH/ZnO/MMT is better than FeOOH/MMT. According to FTIR, changes of pH and TOC, the degradation mechanism was also discussed. PCP was degraded to aromatic ketone and chloro-hydrocarbon compounds and then to H 2 O, CO 2 and HCl.

The alkylation of isobutane/isobutene to produce alkylate was investigated in the presence of Bronsted–Lewis acidic ionic liquids (ILs). The results show that the IL (3-sulfonic acid)-propyltriethylammonium chlorozincinate [HO3SC3NEt3]Cl-ZnCl2 (molar fraction of ZnCl2, x = 0.83) was an efficient catalyst for the alkylation reaction. The conversion of isobutene was about 100% and the selectivity for the C8-alkylate reached 91.7%, in which the mass ratio of trimethylpentane to dimethylhexane was more than 75. The IL reusability was good and its catalytic performance did not significantly decrease after ten reaction cycles. It was also found that a synergetic effect of Bronsted and Lewis acid sites enhanced the catalytic performance of ILs.

Mesoporous solid bases catalysts were prepared by impregnation of a certain amount of alkaline-earth metals species on the synthesized MCF support and used in the methanolysis of PC. Compared with the synthesized SBA-15 solid base catalysts, CaO/MCF catalysts with larger pore size, pore volume and higher active species dispersion exhibited higher catalytic activity. The influences of supported catalyst physicochemical properties and methanolysis conditions were also investigated. The results indicated that methanolysis rate of PC was closed to 100%, and yield of BPA was over 95% under the proper reaction conditions with the excellent performance of 12%CaO/MCF catalyst. The catalyst stability study showed that 12%CaO/MCF had good catalytic activity after five circles. At the same time, the possible methanolysis mechanism of PC was proposed.

In this work, a series of Pd@Al-MSiO2 yolk–shell-structured nanospheres (YSNSs) with different Al contents were synthesized by a facile one-pot method. The EDX elemental analysis and high-magnification TEM image of Pd@Al-MSiO2 YSNSs confirmed that its well-defined yolk-shell structure with a moving Pd core and mesoporous silica shell rich in Al species. Furthermore, Solid state NMR and Py-FTIR results confirmed that Al species grafting mainly formed 4-coordinated Al (AlO4) in the mesoporous silica framework which led to generating abundant Lewis acid sites. The influence of Al species on the physicochemical properties of Pd@Al-MSiO2 YSNSs, as well as their catalytic performance for the hydrogenolysis of glucose to 1,2-propylene glycol (1,2-PG), was investigated. The mesoporous silica shell with abundant Lewis acid sites is a significant contributor to the isomerization of glucose into fructose, while the Pd core plays a role in promoting the hydrogenation of intermediates. The unique hollow space inside the Pd@Al-MSiO2 YSNSs provides a location for the retro-aldol condensation of fructose and consequently avoids direct hydrogenation of fructose. The as-synthesized Pd@Al3-MSiO2 YSNSs shows superior catalytic activity (1,2-PG selectivity of 47.4%, glucose conversion of 95.4%) in the hydrogenolysis of glucose, and far outperforms the Pd/Al3-MSiO2 catalysts. In addition, owing to the influence of the 4-coordinated Al species on the geometry and chemical properties of the mesoporous silica shell, the nanospheres show good stability and reusability over multiple catalytic cycles without significant loss of activity.

High-acid value of bio-oil from biomass is the important reason to restrict its application. Here acid value of bio-oil from waste cooking oils (WCO) was decreased by methyl esterification with the FFAs (Free Fatty Acids) in the bio-oil using SO42-/ZrO2 as a solid acid catalyst. The acid value of the esterification product decreased to 3 mg KOH g−1, and both the kinematic viscosity and the density reached the 0# diesel standard. Other properties were superior to traditional biodiesel, and the obtained product could be used as a diesel with good performance. The activity and reusability of the SO42−/ZrO2 have been studied and the results suggested that the rate of esterification was 96.15% and more than 90% in the fifth esterification. Then kinetics of the reaction has been studied; revealing it to be a zero-order reaction when the methanol is excessive.

The study aimed at preparing porous carbon materials, with superhydrophilic characteristics and developed micro/mesoporous structure (CSB-800), from corn stover by a solvent-free method including pre-carbonization, ball milling, and activation. The effect of pre-carbonization, ball milling on the detailed structural composition and properties especially the hydrophilicity and porous structures were studied, and the potential application of CSB-800 as electrode in supercapacitors was also investigated. The results revealed that pre-carbonization increased the accessibility of raw materials as well as the efficiency of the ball milling with KOH, leading to small carbon particles with good dispersion behavior. Ball milling promoted the porosity, surface energy, hydrophilicity, crystallinity, and graphitization of the carbon materials. CSB-800 exhibited a high specific surface area of 2440.6 m2/g with developed micro and porous structures. The heteroatom nitrogen formed nitrogen-containing groups of N Q and N X, which provided faradaic pseudocapacitance when CSB-800 was used as an electrode material, and this material presented a specific capacitance of 398 F/g at 0.5 A/g in 1 M H2SO4 electrolyte in a three-electrode system, while the value was 243 F/g in a two-electrode system, and the energy density reached 5.01 Wh/kg at a power density of 100 W/kg.

Compared with ionic liquids, deep eutectic solvents (DESs) show many special physical and chemical characteristics, such as low cost, easy synthesis, low toxicity, good biological degradability and compatibility. In this work, a series of DESs based on choline chloride (ChCl) were synthesized and used for the methanolysis of polycarbonate (PC) to obtain the valuable product Bisphenol A (BPA). The most effective DES was ChCl-2Urea which was formed between ChCl and Urea in the molar ratio of 1:2. Using ChCl-2Urea as catalyst, PC conversion was nearly 100% at 130 ℃ and 2.5 h, under this mild reaction condition, BPA yield was over 99%. More importantly, BPA could be easily separated from this reaction system by simple filtration and extraction. DES was recycled and reused without obvious loss of its catalytic activity. In other words, it described a simple, cheap, highly efficient catalytic and environmentally friendly method for PC methanolysis into the valuable product. In addition, this mechanism of PC methanolysis was proposed through experiments and DFT calculations. The kinetics of the reaction was also investigated, indicating that PC methanolysis was a pseudo-first order reaction with an activation energy of 141.47 kJ mol−1.

Aromatic sulfonic acid, p-toluenesulfonic acid (p-TsOH), was employed to pretreat the corn stover in aqueous for improving the enzymatic hydrolysis of cellulose-enriched residue, and was compared to ethanol/water pretreatment. The glucose yield of corn stover from p-TsOH/water pretreatment (97.6 %) was higher than that from ethanol/water pretreatment (89.5 %) after 96 h hydrolysis with high cellulase loading of 15 FPU/g-cellulose. More than 80 % of glucose yield was still obtained with low cellulase loading (7.5 FPU/g-cellulose) after p-TsOH/water pretreatment, while only 65.2 % was obtained after ethanol/water pretreatment. Composition and structure analysis showed that p-TsOH/water pretreatment severely break the fibre, removed more lignin (especially of surface lignin), well increased cellulose accessibility, and resulted in more hydroxyl exposed on the surface. Moreover, more monomeric sugars (xylose and glucose) derived from hemicellulose were released after p-TsOH/water pretreatment, and they could be converted to valuable platform chemical of levulinic acid by simply heating the prehydrolysate.

A supported ruthenium (Ru) nanoparticle on amino-functionalized Fe3O4 (Fe3O4/NH2/Ru) was successfully prepared by a novel and simple one-pot template-free method combined with a metal adsorption-reduction procedure. The characterization results show that the introduced amino group (1,6-hexanediamine) can effectively stabilize the Ru nanoparticles and allow the particles to maintain a narrow size distribution, monodispersity and a regular morphology. Fe3O4/NH2/Ru exhibits excellent catalytic activity for the transfer hydrogenation of nitro compounds by the use of NaBH4 as the hydrogen donor. The higher activity of this catalyst was attributed to the higher dispersion and smaller particle size of Ru nanoparticles, as observed from the characterization results. Moreover, the catalyst can be easily recovered by an external magnetic field, recycled five times and reused without any loss of activity.

Cellulose is the most abundant renewable resource on earth, and its economic utilization has long been a hot research topic. To address these challenges, based on the coexistence of crystalline and amorphous structures within cellulose, we coupled supercritical carbon dioxide (SC-CO2) and cellulase to utilize cellulose subregions. This approach is taken into consideration from the structure of cellulose. Cellulose amorphous regions were enzymatically hydrolysed into reducing sugar, and crystalline regions were converted to nanocellulose, representing efficient use of available raw material. This nanocellulose exhibited different properties with these derived from the traditional method. The smallest effective diameter almost was approximately 5nm, suggesting good uniformity and stability of the nanocellulose. Cellulose characterization results showed that the coupled method exposed more free hydroxyl groups which enhanced the accessibility between the cellulose and substrate, and the stability of nanocellulose. The established process was tested on cotton linters and similar results were obtained.

A nitrosation-reduction method had been applied for the modification of DCE-4 h. It was a kind of non-polar hypercrosslinked resin and synthesized by our group. The functional resin, NR-07, exhibited good adsorption performance for NACs (Nitroaromatics). The adsorption capacity of NR-07 for p-nitrobenzoic acid was almost 1.3 times as much as that of H-103 in 24 h. The adsorption rate of NR-07 calculated by the kinetic function was 1.6 times as much as that of DCE-4h. According to the EA analysis and IR spectrum, the amine and carbonyl group were introduced onto the polymer chains of NR-07. These hydrophilic chemical groups of NR-07 contributed to a higher liquid-film diffusion rate than that of DCE-4h. Besides, the pore volume within 0.46~4.3 nm increased after the modification process, which had a positive effect on the intra-particle diffusion process.

In this work, the alkali-treatment with NaOH solution was used to reduce the crystal sizes of original zeolite Y. Acidic supports of two bifunctional catalysts consisted of γ-alumina binder and zeolite Y (original or alkali-treated) with different crystal size distributions. Most of metal platinum was selectively deposited on the γ-alumina component via the electrostatic adsorption method. Given the above, it can be deduced that (de)hydrogenation reaction occurred inside the zeolite micropores at a low probability, while active protonic acid sites catalyzing the skeletal conversions of alkene intermediates were exclusively located on zeolite Y. Therefore, the number of active protonic sites that intermediates potentially encountered between two metal sites can be regarded as being proportional to diffusion distances of intermediates within the zeolite micropore structures. Moreover, the above-mentioned diffusion distances were greatly associated with the zeolite crystal sizes. Isomerization reactions of n-decane (n-C10) on two bifunctional catalysts were investigated, and results indicated that the catalyst, with alkali-treated zeolite as the acidic component, performed better than the catalyst, for which original zeolite provided the acid function, in restraining the secondary reactions. This can be attributed to the shortened diffusion distances of intermediates inside the zeolite micropores, which was caused by reducing the zeolite crystal size.

Zn-acetate-containing ionic liquid (IL), 1-butyl-3-methylimidazolium acetate-promoted zinc acetate (2[Bmim][OAc]-Zn(OAc)2) was synthesized and used to catalyze the methanolysis of poly(lactic acid) (PLA). In this study, it was found that not only the methanolysis condition was milder compared with reported literatures, but also the high conversion of PLA and the yield of product methyl lactate were obtained when this Zn-acetate-containing IL was used as catalyst. The influences of technological parameters on PLA methanolysis were investigated and the optimum reaction conditions were obtained. Under the following conditions of catalyst (n[Bmim][OAc]:nZn(OAc)2 = 2.0:1, 0.04 g), n(CH3OH):n(PLA) = 5.0:1 and PLA (4.0 g) at 110 °C for 2.0 h, the PLA conversion and the methyl lactate yield were over 97% and 92%, respectively. Compared with the conventional ILs and other traditional catalysts, this Zn-acetate-containing IL exhibited excellent catalytic performance and the advantage of small dosage. The IL could be reused for 5 times, both FT-IR and TGA results indicated that the spectra of the reused IL were almost similar to those of the fresh one. Moreover, a possible mechanism of PLA methanolysis catalyzed by [Bmim][OAc]-Zn(OAc)2 was proposed through the experiments. The reaction kinetics was also investigated, and the results showed that it was a pseudo-first order kinetic reaction with an activation energy of 20.96 kJ/mol.

The present study investigates a new solvent system for the dissolution of chitosan and a new method for preparing chitosan membranes. First, aqueous tartaric acid was used to pretreat chitosan. Then, the chitosan was precipitated with ethanol or other regenerating agents, and 1.5 mL of 1-ethyl-3-methylimidazolium acetate ([EMIM]AC) was added to obtain translucent suspensions. The chitosan membranes were prepared by casting the suspensions on glass plates and allowing solvent evaporation. The structure and properties of the films were investigated by SEM, FT-IR, XRD and TGA. Also, the mechanical properties, as well as physical and chemical characteristics, of the chitosan films were evaluated. The results indicated that the optimum dissolution time was 10 min and the most suitable drying temperature was 60 °C. The thus-prepared film was moderately thick (about 0.02 mm) and had a smooth surface, without curling. The chitosan film prepared by ethanol regeneration had a tensile strength of up to 24 MPa, a minimum swelling degree of 78%, and a water vapor transmission rate of 270 g m−2 d−1 without the addition of plasticizer.

A petroleum aromatic-rich component was used to prepare mesophase pitch by thermal condensation. In-process hydrogenation method was employed to achieve the hydrogenation reaction of intermediates generated during the thermal reaction using tetrahydronaphthalene (THN) as a hydrogen donor. Impacts of in-process hydrogenation on the properties of intermediates and mesophase pitches were investigated. It was found that the in-process hydrogenation was conducive to the generation of hydrogenated intermediates with concentrated extracted component distribution, uniform molecular structure and abundant naphthenic structures. The characterizations of mesophase pitches showed that the in-process hydrogenation contributed to the preparation of mesophase pitch with concentrated extracted component distribution, low softening point, large domain structure and ordered crystal structure. This was due to the increasing contents of naphthenic structures in intermediates. Moreover, the increase of methylene bridges in the product was the critical reason for improving the product's properties.

This study presents the utilization of a binary catalyst composed of metal-loaded modified SBA-15 (M/SBA-15) and phosphotungstic acid (H3PW12O40) for ethylene glycol (EG) production from direct catalytic conversion of cellulose. M/SBA-15 (M = Ru, Au, Pd, Pt, Rh and Ni) catalysts were prepared using the impregnation method and characterized by means of XRD, N2 physisorption, TEM and H2-temperature-programmed reduction (H2-TPR) techniques. Their catalytic performance was then studied in detail on the basis of cellulose conversion and the selectivity of polyols and EG. The results showed that the mesoporous structure of the SBA-15 sample was well maintained after the metal-loaded modification, and almost all of the selected catalysts gave about 100% conversion of cellulose. However, the selectivity for EG was greatly different. Among the various binary catalysts, the combination of Rh/SBA-15 and H3PW12O40 gave the best selectivity to EG (55.5%), whereas the worst selectivity of EG (11%) was obtained over the Au/SBA-15 and H3PW12O40 system under identical conditions. In addition to phosphotungstic acid, other W compounds were also studied in combination with the Ru/SBA-15 catalyst. The results showed that the EG selectivity depended on the W compounds as follows: H4SiW12O40 < H2WO4 < H3PW12O40. Therefore, the binary catalyst of Rh/SBA-15 and H3PW12O40 showed the greatest potential for EG production from direct catalytic conversion of cellulose.

Effects of water on a catalytic reaction system for reductive alkylation of

An alkylketene dimer (AKD) emulsion was prepared using a neotype polymeric emulsifier. The water resistance, surface tension, stability, grain diameter, and contact angle of the obtained AKD emulsion were investigated under different conditions, such as emulsification temperature, emulsification time, solids content, and amount of emulsifier. The experimental results demonstrated that the sizing effect of the AKD emulsion was fairly good under the following conditions: emulsification temperature, 75°C; emulsification time, 9 min; solids content, 10%; and the amount of emulsifier, 3%.

Naphthene-based aromatic-rich fraction was modified by tetrahydronaphthalene and polyethylene glycol to obtain modified materials which were selected to prepare mesophase pitches by a direct condensation method. The structural composition of modified materials were characterized by simulated distillation (SIMDIS), elemental analysis, Fourier transform infrared spectrometry (FTIR) and 1H nuclear magnetic resonance (1H NMR) spectroscopy. Influences of the naphthenic structures and alkyl chains in modified materials on the formation and development of mesophase structures were investigated by analyzing variations in optical texture, softening point, carbon residue, molecular and microcrystal structure of mesophase pitch. Results showed that the alkyl structures in modified materials treated by tetrahydronaphthalene and polyethylene glycol were mainly naphthenic structures and alkyl chains, respectively. The existence of alkyl structures in modified materials was beneficial for the formation of mesophase with high quality. Moreover, the naphthenic structures had a better improving effect than alkyl chains. Abundant naphthenic structures or an appropriate amount of alkyl chains in feedstock contributed to the preparation of mesophase pitch with large domain structure, low softening point, high carbon residue and ordered microcrystal structure.

Bronsted–Lewis acidic ionic liquids (IL) were used in the esterification of glycerol and acetic acid to produce glycerol triacetate. The results show that the IL (3–sulfonic acid)–propyltriethylammonium chloroironinate [HO3S–(CH2)3–NEt3]Cl–[FeCl3]x (molar fraction of FeCl3, x = 0.67) was an efficient catalyst for the esterification reaction. The yield of glycerol triacetate and its content were greater than 98 % when reacted under reflux for 4 h. It was observed that a synergistic effect of Bronsted and Lewis acid sites enhanced the catalytic performance of IL. The reusability of IL was good. After six reaction cycles, the glycerol triacetate yield and concentration were still greater than 98 %. Likewise, the Bronsted–Lewis acidic IL was an efficient catalyst for esterification reactions of high boiling points alcohols with acetic acid.

The self-assembly heteropoly acid solution can be directly used for catalyzing oxidative desulfurization (ODS) of model fuel with O 2 as oxidant in high sulfur removal. The sulfur compounds in model fuels can all be nearly completely oxidized. The oxidation mechanism of thiophenic sulfurs is proposed. In the ODS process, the self-assembly heteropoly acid solution acts as both the catalyst and the excellent extracting agent, and the oxidation and extraction are performed simultaneously.

A series of functionalized heteropoly acid catalysts with two PEG chains and an Anderson-type polyoxoanion IMo6O245− have been in situ synthesized, and applied for catalytic oxidative desulfurization coupling with extraction (oxidative-extractive desulfurization, OEDS). Two PEG chains endow the catalyst with a good extracting ability for sulfur compounds, particularly, their corresponding oxidative products. The oxidation and extraction can be performed simultaneously. No additional extracting agent is added after oxidation. The mechanism of OEDS is proposed. The effect factors for OEDS of model gasoline with H2O2 and O2 as oxidants are respectively investigated, and the optimum conditions are respectively obtained. The H2O2 OEDS system is more efficient, rapid and has low energy consumption. It just takes several tens of minutes under the mild conditions to achieve the complete removal of dibenzothiophene (DBT), benzothiophene (BT) and thiophene in model gasoline. The novel H2O2 OEDS system has been also applied for the desulfurization of real gasoline. The vast majority of sulfides in real gasoline are removed after OEDS, and the content of sulfur from 110 ppm can be reduced to 10 ppm. Moreover, the functionalized heteropoly acid catalyst has showed good recyclability.

Ruthenium (Ru) nanoparticles were prepared using polyoxyethylene–polyoxypropylene–polyoxyethylene triblock copolymer (P123) micelles in water as a stabilizing agent. The P123–Ru micellar catalyst was first used in the hydrogenation of α-pinene to pinane, and the selectivity for cis-pinane reached 98.9%. This result is attributed to the formation of vesicles. The isolated catalyst phase could be used seven times with no treatment, and its catalytic activity and selectivity were almost unchanged. The preparation process of the catalyst and hydrogenation reaction of α-pinene was under mild and environmentally friendly conditions. This research offers an effective method for the hydrogenation of α-pinene and provides a reference for other hydrophobic natural products in hydrogenation reactions.