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The continuous flow hydrogenation of N-methylpyrrolidone which catalyzed by Pt/V/HAP (Pt/V molar ratio = 1 : 0.5) was achieved running for 100 h with solvent-free, and the N-methylpyrrolidine yield was above 85.21%.

Brӧnsted acidic poly ionic liquid (PIL-M) was successfully prepared by free-radical polymerization. The surface area of the heterogeneous catalyst was 301.1 m2/g. The result of thermogravimetric (TG) proved that PIL-M had good thermal stability (decompose at 410 °C). The optimal reaction condition was as follows: 6 wt% catalyst amount, reaction temperature 80 °C, the ratio of methanol to oleic acid 9:1 and reaction time 3 h. Under the optimal condition, the yield of methyl oleate was up to 95.9%. The excellent catalytic activity of PIL-M in the product of biodiesel benefit from its excellent properties such as high surface area (301.1 m2/g) and hierarchical nanopores. Compared with commercial resin (Amberlyst 15) and other catalysts, PIL-M showed better catalytic activity. The yield of methyl oleate was still over 90% after four times reuse. The structure of PIL-M kept stable after four times reuse, which was confirmed by the FT-IR spectrum.

A novel polyionic liquid for esterification was synthesized by phenolic condensation. Different characterization techniques were applied, and the result showed that the catalyst had high acidity am...

In this work, N-methyl-2-pyrrolidonium (NMP) was acidized using hydrochloric acid to obtain [Hnmp]Cl first, which was then reacted with FeCl3 to prepare a series of inexpensive tunable [Hnmp]Cl·xFeCl3 (x = 0.2–2.0) ionic liquids (ILs) for the extractive and oxidative desulfurization of model oils. The Lewis acidities of these ILs were tested by the Fourier transform infrared (FT-IR) method, which indicated that when the x value of [Hnmp]Cl·xFeCl3 was above 1.0, the ILs exhibited Lewis acidity. The extraction results showed that the acidification of NMP reduced its dissolubility ability toward dibenzothiophene (DBT) and its Lewis acidity played a determining role in extractive desulfurization. In the catalytic oxidation removal process of the DBT model oil in the presence of H2O2, electron paramagnetic resonance (EPR) and scavenger experiments showed that the hydroxyl radical (˙OH) plays a key role and the superoxide anion radical (O2˙−) has a minor function. [Hnmp]Cl·1.5FeCl3 IL showed excellent recycling performance, which was due to its high dissolving capacity (23 700 ppm) for dibenzothiophene-sulfone (DBTO2).

Four metal phthalocyanines (Pc-4, 8, 12, 16) functionalized ionic liquids were polymerized on the surface of silica gel as adsorbent materials. They were characterized by FT-IR, BET, SEM and TEM measurements. The characterization results proved that the adsorbents were prepared successfully. Their adsorptive desulfurization performances to dibenzothiophene in model oil at room temperature and atmospheric pressure were investigated in detail. The results showed that the adsorptive desulfurization effect of P-4 was best. The optimal amount of adsorbent was 10 g/100 mL model oil. The maximum amount of DBT adsorbed was 52.41 mg/g, superior to some previously reported adsorbents. The adsorption equilibrium and kinetics of this adsorbent were also examined. The adsorption behavior fitted well to Freundlich isotherm model, pseudo-second-order kinetics model and Weber and Morris kinetics model. Adsorption and regeneration by solvent processes were performed 10 times, and the adsorption capacity of the adsorbent did not decrease obviously. P-4 also had a good adsorption effect on different sulfur compounds, and the order of removal was DBT > BT > 2-MTH > TH.

Iron phthalocyanine (PcFe) was loaded on Ti-MCM-41 as visible light photocatalyst (R-PcFe/Ti-MCM-41). Dibenzothiophene (DBT) was photooxidized using R-PcFe/Ti-MCM-41 as a photocatalyst, air as an oxidant, and ionic liquid as the extraction agent during visible light irradiation at room temperature and ambient conditions. The results indicated that photocatalytic efficiency of the amino iron phthalocyanine (NH2-PcFe)/Ti-MCM-41 was superior to the other substituent groups. The DBT content in the model oil decreased from 1000 to 44 μg/mL with 95.6% removal rate under the optimal reaction conditions (model oil 10 mL, photocatalyst NH2-PcFe/Ti-MCM-41 0.02 g, loading amount of NH2-PcFe 0.3 g/g, air flow rate 100 mL/min, reaction time 2 h, room temperature). The kinetics of photocatalytic oxidation of DBT follows first-order kinetics with a rate constant of 1.319 h−1 and halftime of 0.525 h. The photocatalyst NH2-PcFe/Ti-MCM-41 was reused for five times, and the catalytic activity decreased slightly. The photocatalytic oxidation system demonstrated significant desulfurization effects on different sulfur compounds and real gasoline, and the sulfur content of the actual gasoline could be reduced from 1000 to 78 ppm.

The effective dissolution of cellulose prepares for its subsequently full utilization. Ionic liquids (ILs) are attractive options for “green” dissolution of cellulose. A series of morpholinium-based ILs were synthesized and applied in dissolution of cellulose. The ultrasonic assisted saturated calcium chloride solution was used to activate cellulose. The remarkable decrease (from 87% to 65%) in crystallinity of cellulose facilitated dissolution process. The type of head-corn cations significantly increased polarity (ET(30)) and hydrogen bond acidity (α) of ILs. N-Allyl-N-methylmorpholinium-based ILs showed the highest ET(30) and α (59.11 kcal mol−1 and 0.51) compared to 1-Allyl-3-methylimidazolium-based ILs (57.41 kcal mol−1 and 0.46) and 1-Allyl-3-methylpyridinium-based ILs (49.36 kcal mol−1 and 0.33) owing to the electron-rich center of oxygen in the morpholine ring. The type of anions dominated the ability to accept hydrogen bond of ILs. Formate, acetate and bisulfate contributed more hydrogen bond basicity (β) (0.84, 0.88 and 0.91) for N-allyl-N-methylmorpholinium-based ILs in comparison with other anions. Additionally, morpholinium-based ILs exhibited appropriate viscosity. Above-mentioned performances jointly improved the dissolution of cellulose in morpholinium-based ILs. This study demonstrated the potential of using morpholinium-based ILs as a class of efficient solvents to dissolve cellulose.

A series of choline chloride-based deep eutectic solvents (ChCl-DESs) were synthesized and characterized, and their performance in the dissolution of cellulose was investigated. The hydrogen-bond donors significantly (β-value) affected the properties of ChCl-DESs, causing differentiated dissolution performances. ChCl- imidazole (Im) showed the highest Hammett acidity function (1.869), hydrogen bond basicity (0.864), and dipolarity/polarizability effect (0.382) among the ChCl-DESs. The ChCl-Im showed the lowest pseudo-activation energy for viscous flow (31.76 kJ mol-1) among the ChCl-DESs. The properties of ChCl-Im caused the highest solubility of cellulose (2.48 wt.%) relative to the other ChCl-DESs. Polyethylene glycol (PEG), as a co-solvent, significantly (β-value) enhanced the accessibility of ChCl-Im to cellulose by breaking the supramolecular structure of cellulose, promoting its dissolution. The decrystallization of ChCl-Im-coupled PEG approximately doubled the dissolving capabilities, and the solubility increased by more than 80% in comparison with only ChCl-Im. The cellulose was directly dissolved by ChCl-Im-coupled PEG, and no other derivatives were produced.

Several metal-based ionic liquids (ILs) were synthesized and used as extractants for the desulfurization of dibenzothiophene (DBT) in simulated fuel oil. The effects of several anion and metal ions, n(ILs)/n(metal) as mole ratio, VIL/Voil and extractive times on the removal ratio of DBT were investigated in detail. The results showed that [BMIM]HSO4/FeCl3 (BMIM was short for 1-butyl-3-methyl imidazole) was superior to the other ILs for the extractive desulfurization. A total of 100% of DBT was removed at room temperature in 5 min with V [ BMIM ] HSO 4 / FeCl 3 / V oil = 1 : 1 . The extractive activity of [BMIM]HSO4/FeCl3 IL did not change almost after five runs. Extractive desulfurization of different sulfur compounds and commercial diesel fuel oil were also examined. The removal ratios of the sulfur compounds as the reaction substrates were all over 90% and the sulfur content of commercial diesel oil decreased to 120 ppm from 12,400 ppm.

Inexpensive N-methyl-pyrrolidone (NMP)-based ionic liquids (ILs) are synthesized by coordinating N-methyl-pyrrolidone with anhydrous FeCl 3 or ZnCl 2 . The introduction of metal chlorides lowers the solubility of NMP for actual diesel. The obtained C 5 H 9 NO·0.3FeCl 3 IL shows remarkable extraction ability for dibenzothiophene (DBT) with Nernst partition coefficients ( k N ) above 7.5, which can be attributed to its low viscosity and bifunctional extractive groups of five-membered ring of NMP and unoccupied orbitals of Fe ion. The oxidative desulfurization of DBT using H 2 O 2 as oxidant and ILs as extractants are investigated. The scavenger experiments and electron paramagnetic resonance (EPR) measurement verify the active species is hydroxyl radical ( OH) responsible for the oxidation of DBT. FeCl 3 -based ILs show much better effects in catalyzing H 2 O 2 to generate OH than ZnCl 2 -based ILs. The process and mechanism for extraction and catalytic oxidation of DBT in an oil–ionic liquid–H 2 O 2 system are proposed. The C 5 H 9 NO·0.3FeCl 3 IL shows excellent recycling performance. After six-run experiment, there is only little loss in activity, which can be ascribed to the high solubility (18,190 ppm) of dibenzothiophene-sulfone (DBTO 2 ), the main oxidation product of DBT, in the IL.

Heterojunctions of g-C3 N4 /Al2 O3 (g-C3 N4 =graphitic carbon nitride) are constructed by an in situ one-pot hydrothermal route based on the development of photoactive γ-Al2 O3 semiconductor with a mesoporous structure and a high surface area (188 m(2) g(-1) ) acting as electron acceptor. A structure modification function of g-C3 N4 for Al2 O3 in the hydrothermal process is found, which can be attributed to the coordination between unoccupied orbitals of the Al ions and lone-pair electrons of the N atoms. The as-synthesized heterojunctions exhibit much higher photocatalytic activity than pure g-C3 N4 . The hydrogen generation rate and the reaction rate constant for the degradation of methyl orange over 50 % g-C3 N4 /Al2 O3 under visible-light irradiation (λ>420 nm) are 2.5 and 7.3 times, respectively, higher than those over pristine g-C3 N4 . The enhanced activity of the heterojunctions is attributed to their large specific surface areas, their close contact, and the high interfacial areas between the components as well as their excellent adsorption performance, and efficient charge transfer ability.

The pH-responsive cellulose-g-poly[2-(diethylamino)-ethyl methacrylate] (cellulose-g-PDEAEMA) copolymers were successfully synthesized by atom transfer radical polymerization (ATRP) in the ionic liquid 1-allyl-3-methylimidazolium chloride ([AMIM]Cl). As the functional monomer 2-(diethylamino)ethyl methacrylate (DEAEMA) hardly dissolved in [AMIM]Cl, we used ethyl alcohol as the cosolvent to increase its solubility and thereby form a homogeneous system. Compared with the synthetic mechanism for the heterogeneous system, generation of the byproduct poly[2-(diethylamino)ethyl methacrylate] (PDEAEMA) in the homogeneous system was reduced and the ATRP reaction was easily controlled. Optimum reaction condition was attained at the CuBr/PMDETA/DEAEMA/ethyl alcohol molar ratio of 1:15:150:300. Kinetic analysis confirmed the reaction was living and controllable. Cellulose-g-PDEAEMA was characterized through FTIR, 1H NMR, TEM and GPC. The results showed that the PDEAEMA brush was covalently bonded to the cellulose backbone and its molecular weight distribution was narrow. In addition, the resultant copolymer could self-assemble into spherical micelles and showed the pH-sensitivity, implying its potential application as biomedical materials.

Novel Al2O3/g-C3N4 heterojunction photocatalysts were fabricated through ultrasonic dispersion method. Al2O3, obtained via solution combustion, contained amorphous ingredient with lots of defect sites and was used as active component for transferring photo-induced electrons of g-C3N4. G-C3N4 was grafted surface hydroxyl groups in the presence of ammonia aqueous solution to combine with Al2O3 possessing positive charges via hydrogen bond. The XRD, SEM, element map, TEM, HRTEM, FT-IR, and XPS results indicate that these synthesized materials are two-phase hybrids of Al2O3 and g-C3N4 with interaction. The photocatalytic results for the degradation of rhodamine B (RhB) indicate that the most active heterojunction proportion is 60wt.% g-C3N4:40wt.% Al2O3, the visible light photocatalytic activity of which is 3.8 times that of a mechanical mixture. The enhanced performance is attributed to the high separation efficiency of photo-induced electrons from the LUMO of g-C3N4 injected into the defect sites of Al2O3, which is verified by photoluminescence spectroscopy (PL) and surface photovoltage (SPV) measurements. The electron paramagnetic resonance (EPR) signals and radical scavengers trapping experiments reveal holes (h(+)) and superoxide anion radical (O2(-)) are the main active species responsible for the degradation of RhB.

Heterostructured BiOBr/Bi24O31Br10 nanocomposites with surface oxygen vacancies are constructed by a facile in situ route of one-step self-combustion of ionic liquids. The compositions can be easily controlled by simply adjusting the fuel ratio of urea and 2-bromoethylamine hydrobromide (BTH). BTH serves not only as a fuel, but also as a complexing agent for ionic liquids and a reactant to supply the Br element. The heterojunctions show remarkable adsorptive ability for both the cationic dye of rhodamine B (RhB) and the anionic dye of methylene orange (MO) at high concentrations, which is attributed to the abundant surface oxygen vacancies. The sample containing 75.2% BiOBr and 24.8% Bi24O31Br10 exhibits the highest photocatalytic activity. Its reaction rate constant is 4.0 and 9.0 times that of pure BiOBr in degrading 50 mg L(-1) of RhB and 30 mg L(-1) of MO under visible-light (λ400 nm) irradiation, respectively, which is attributed to the narrow band gap and highly efficient transfer efficiency of charge carriers. Different photocatalytic reaction processes and mechanisms over pure BiOBr and heterojunctions are proposed.

A novel method for preparing epoxy graft poly(St-acrylate) composite latex with high graft ratio has been devised. First, esterification was carried out between acrylic acid and an epoxy resin using the monomer as the solvent. The obtained sample, still in solution in the monomer, was emulsified to miniemulsion droplets together with other monomers. Finally, the epoxy graft acrylate composite latex was prepared by miniemulsion copolymerization. This technology will eliminate pollution arising from the organic solvent when solvent-borne systems are used. The enhanced graft ratio was confirmed by FTIR and 1H NMR measurements. The results indicated that the acrylic monomer was grafted onto the epoxy chain. TEM showed the graft composite latex to have a spherical structure with diameter 100 nm. The adhesive performance and anti-corrosive properties on a steel substrate, as measured by salt-spray resistance, were maximized when 4.0% acrylic acid was added to the epoxy resin. Dynamic mechanical analysis (DMA) has been employed to test the damping properties of the composite latex coatings. It was interesting that the tan δ peak values of the coatings were as high as 2.15, clearly exceeding those of general damping materials. Our findings suggest great potential for the composite latex in the field of functional steel coatings.

A facile and fast method was developed for the preparation of novel BiOCl/Bi 24 O 31 Cl 10 heterojunctions via a self-combustion of ionic liquids (ILs) route. The ILs were prepared from Bi(NO 3 ) 3 ·5H 2 O and diethylamine hydrochloride ((C 2 H 5 ) 2 NH·HCl). The photocatalysts were obtained by heating the ILs to combustion. In the ILs system, (C 2 H 5 ) 2 NH·HCl serves not only as the source of cation in IL, but also as the main fuel. The prepared composites exhibit noticeable visible light photocatalytic activity in the degradation of organic pollutants, including anionic dye methyl orange and cationic dye rhodamine B, which is attributed to the narrow band gap (2.3 eV) and the effective electrons transfer from the conductive band of Bi 24 O 31 Cl 10 to that of BiOCl, improving the separation efficiency of the photo-generated electron/hole pairs. The heterojunction containing 60.4% BiOCl and 39.6% Bi 24 O 31 Cl 10 exhibits the highest photocatalytic activity. The heterojunction shows dramatic adsorption performance for cationic dye rhodamine B because of its surface negative charges. The radical scavengers result shows that hole is the main reactive species responsible for the degradation of pollutants and superoxide radials are also involved in the photocatalytic process. The results obtained may provide a new sight for broadening the application of ILs in the preparation of nanomaterials and for the in-situ one-step synthesis of heterostructural materials.

A facile and green method was developed for the simultaneous doping of nitrogen, boron, and fluorine in TiO 2 by H 2 TiO 3 via a microwave-assisted route. The ionic liquid (IL) [BMIm]BF 4 serves not only as microwave absorbent but also as a dopant. The IL also shows the ability to self-assemble under microwave irradiation, which causes it to act as an inhibitor for the growth of the TiO 2 particles. The N–B–F-tri-doped TiO 2 obtained exhibits large specific surface area, small crystal size, and a mesoporous structure, and the mechanism for the formation of the N–B–F-tri-doped TiO 2 was proposed. The prepared materials exhibit excellent visible light photocatalytic activity in the degradation of organic pollutants, including methyl orange, rhodamine B, Orange G, and reactive red X, which is attributed to the presence of a Ti–B–N structure on the TiO 2 surface, inducing a narrow band gap of 2.78 eV, and the synergistic effects of N, B, and F, which improve the separation efficiency of the photo-generated electron/hole pairs. The results obtained may provide a new sight for the application of ILs in the microwave-assisted preparation of nanomaterials.

Three low-cost types of complex solvents systems were carried out to dissolve cellulose, which were NaOH/urea/acetamide, NaOH/urea/tetraethyl ammonium chloride, and NaOH/acetamide/tetraethyl ammonium chloride. As an effective dissolution, NaOH/acetamide/tetraethyl ammonium chloride behaved as the optimum system, and the solubility was 89 % under the conditions of: NaOH 8 wt%, acetamide 10 wt%, tetraethyl ammonium chloride 6 wt%, distilled water 76 wt%, and freezing temperature −5°C. With the analysis of Ubbelohde viscometer, infrared spectra (FTIR), wide-angle X-ray diffraction (XRD), and thermogravimetric analysis (TGA) for the original and regenerated cellulose samples, it was indicated that the viscosity-average molecular weight had no significant changes in the dissolution process, the crystalline structure of cellulose was converted to cellulose II from cellulose I in native cellulose, and the regenerated cellulose had a good thermal stability.

Three kinds of imidazole based dicationic [C2(Mim)2], [C3(Mim)2], [C4(Mim)2] with traditional counter anion HSO 4 - ionic liquids (ILs) were synthesized. Key physicochemical properties, such as thermal stability, solubility in common solvents, acidic property and corrosion of ILs for Austenitic stainless steel 316 were determined. Esterification of alcohols by carboxylic acids has been carried out at room temperature in a group of imidazole dicationic ionic liquid. The catalytic performance was found to be much better than that of conventional non-cation functionalized ionic liquids and the corrosion was five times weaker than sulfuric acid. The esters were easily recovered due to immiscibility with the ionic liquid and reported imidazole dicationic ionic liquids were a promising catalyst for esterification reaction.

Nitrogen-doped Degussa P25 TiO 2 –amorphous Al 2 O 3 composites were prepared via facile solution combustion. The composites were characterised using X-ray diffraction, high-resolution transmission microscopy, scanning electron microscopy, nitrogen adsorption–desorption measurements, X-ray photoelectron spectroscopy, UV–vis light-diffusion reflectance spectrometry (DRS), zeta-potential measurements, and photoluminescence spectroscopy. The DRS results showed that TiO 2 and amorphous Al 2 O 3 exhibited absorption in the UV region. However, the Al 2 O 3 /TiO 2 composite exhibited visible-light absorption, which was attributed to N-doping during high-temperature combustion and to alterations in the electronic structure of Ti species induced by the addition of Al. The optimal molar ratio of TiO 2 to Al 2 O 3 was 1.5:1, and this composite exhibited a large specific surface area of 152 m 2 /g, surface positive charges, and enhanced photocatalytic activity. These characteristics enhanced the degradation rate of anionic methylene orange, which was 43.6 times greater than that of pure P25 TiO 2 . The high visible-light photocatalytic activity was attributed to synthetic effects between amorphous Al 2 O 3 and TiO 2 , low recombination efficiency of photo-excited electrons and holes, N-doping, and a large specific surface area. Experiments that involved radical scavengers indicated that OH and O 2 − were the main reactive species. A potential photocatalytic mechanism was also proposed.

Nano-TiO2 was prepared in [Bmim]BF4 ionic liquid (IL) via microwave radiation. The [Bmim]BF4 IL that contained the as-prepared TiO2 was mixed with dibenzothiophene (DBT) in n-octane, which was used as model oil for photocatalytic desulfurization under the UV irradiation. In this process, IL was used not only as microwave absorption medium for preparation of TiO2 but also as extractant for DBT. The effect of microwave time on the photocatalytic desulfurization ability of prepared TiO2 in the presence of O2 was investigated. 98.2% and 94.3% sulfur could be removed from model oil and actual diesel oil, respectively, in 10 h UV irradiation under the conditions that V(IL)/V(oil) = 1:5, air flow = 200 mL/min. The [Bmim]BF4 IL was recycled five times with a slight decrease in desulfurization efficiency.

ZnO/polystyrene (PSt) composite nanoparticles with high grafting efficiency have been prepared by anchoring 4,4′-azobis(4-cyanovaleric acid) (ACVA) onto the surface of ZnO nanoparticles, and then exploiting its azo group to initiate polymerization of styrene monomer to synthesize composite nanoparticles. The polymerization mechanism of these ZnO/PSt composite nanoparticles with high graft efficiency is discussed. FTIR and XPS confirmed that ACVA had been covalently anchored on the surface of the ZnO nanoparticles via γ-glycidoxypropyl trimethoxysilane. The anchoring percentage of ACVA on ZnO and the grafting efficiency of the ZnO/PSt composite nanoparticles were analyzed by thermo-gravimetric analysis (TGA), and were estimated as 17% and 85%, respectively. The effect of the amount of ZnO with anchored ACVA on conversion and grafting efficiency of styrene was also investigated. TEM proved the presence of ZnO nanoparticle appeared to be monodisperse in nanosize in polystyrene composite nanoparticles. SEM showed that ZnO nanoparticles could be homogeneously dispersed in PVC film by preparing surface-grafted ZnO/PSt nanoparticles. The polymer chains grafted onto the nanoparticle surface enhanced the compatibility between the ZnO nanoparticles and PVC matrix. The PVC composite film presented a perfect anti-UV property, which can improve UV degradation resistance of PVC film.

One-step oxidative desulfurization of dibenzothiophene (DBT) using cyclohexanone peroxide (CYHPO) was performed in the presence of N-alkyl-imidazolium-based ionic liquids (ILs). CYHPO is an oil-soluble oxidant and ILs are employed as extractants. The effect of the ILs, the molar ratio of CYHPO/S (O/S), volume ratio (VIL/Vmodel oil), reaction time (T), and reaction temperature (t) were investigated in detail. The results showed that the desulfurization ability of the ILs followed the order [OMim]BF4 > [HMim]BF4 > [BMim]BF4, reversing the length of the alkyl group to the imidazolium ring. When IL [OMim]BF4 was used, O/S was 2 and VIL/Vmodel oil was 1:1, and 93.5% of DBT in the model oil was removed at 40°C for 30 min. The desulfurization rate of gasoline was 70.8% under optimal conditions. IL ([OMim]BF4) could be recycled for five times without a significant decrease in activity.

A new C5H9NO·SnCl2 coordinated ionic liquid (IL) was prepared by reacting N-methyl-pyrrolidone with anhydrous SnCl2. Desulfurization of dibenzothiophene (DBT) via extraction and oxidation with C5H9NO·SnCl2 IL as extractant, H2O2 and equal mol of CH3COOH as oxidants was investigated. The Nernst partition coefficients kN of C5H9NO·SnCl2 IL for the DBT in n-octane was above 5.0, showing its excellent extraction ability. During the oxidative desulfurization process, the optimal molar ratio of H2O2/DBT was six. Sulfur removal of DBT in n-octane was 94.8% in 30 min at 30 °C under the conditions of H2O2/DBT molar ratio of six and V (IL):V (oil) = 1:3. Moreover, the sulfur removal increased with increasing temperature because of the high reaction rate constant, low viscosity, and high solubility of dibenzothiophene-sulfone in the IL. The kinetics of oxidative desulfurization of DBT was also investigated, and the apparent activation energy was found to be 32.5 kJ/mol. The IL could be recycled six times without a significant decrease in activity.

Two kinds of alkylimidazolium salts containing dimethyl phosphate or diethyl phosphate were obtained as room temperature ionic liquids synthesized by one step, and both of them have the ability to dissolve untreated cellulose. Especially, 1-ethyl-3-methylimidazolium diethylphosphonate ([EMIM]DEP) could obtain 4 wt% cellulose solution within 10 min under 90. The effects of dissolution temperature on cellulose dissolution time and degree of polymerization were investigated. As dissolution temperature increased, dissolution time was greatly reduced. Both the original and regenerated cellulose samples were characterized with wide-angle X-ray diffraction, thermogravimetric analysis and scanning electron micrograph. The results showed that the crystalline structure of cellulose was converted to cellulose II from cellulose I in native cellulose. It was also found that the regenerated cellulose had good thermal stability with [EMIM]DEP ionic liquid.

Efficient separation of acetaldehyde from glyoxal (CAS number: 107-22-2) reaction mixture using a gas stripping (GS) technique is investigated experimentally. A non-equilibrium model for describing the GS process is proposed and solved with a Newton-homotopy method. The steady-state performances of the GS column are investigated by a non-equilibrium model. The effects of liquid–gas ratio, feeding temperature and theoretical plate number on the residue acetaldehyde concentration are examined in detail. The simulating results are closed to the experimental data. According to the simulation results, liquid–gas ratio 1.6, feeding temperature 313 K and theoretical Plate 12 are the optimum operation condition for getting an acetaldehyde concentration of below 0.5 wt%.

Mixed amorphous and crystalline MgAl2O4 nanopowders with visible light-induced photocatalytic activity were prepared via a simple solution combustion method using glycine and urea as fuel mixtures. The obtained samples were characterized by X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray, transmission electron microscopy, Brunauer–Emmett–Teller (BET) surface area, thermogravimetry, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and UV–Vis diffuse reflection spectrum. The results showed that the combustion was almost complete, the crystallinity and crystallite size of MgAl2O4 increased with the increase of fuels, and there was N atoms doped in the catalysts. The MgAl2O4 containing amorphism had photo-absorption ability in visible light region. The photocatalytic results for degradation of methylene blue (MB) indicated that the combustion-synthesized samples had photocatalytic activity, whereas the annealed well crystalline MgAl2O4 nanopowders had none. The MgAl2O4 sample containing about 45.6% crystalline and 55.4% amorphous materials showed the highest photocatalytic activity, with a 99.5% MB removal in 100 min under visible light irradiation. The fluorescence spectra verified that the greater the formation rate of OH radicals, the higher the photocatalytic activity achieved.

In this work, several ionic liquids based on pyridinium cations are prepared. The ionic liquids are employed as phase-transfer catalysts (PTCs) for phase-transfer catalytic oxidation of dibenzothiophene (DBT) dissolved in n -octane. The partition coefficients of DBT between ionic liquids and n -octane are investigated. Then H 2 O 2 –formic acid is used as an oxidant and ionic liquids are used as PTCs. The reaction turns to be heterogeneous and desulfurization rate of DBT increased apparently. When IL ([BPy]HSO 4 ) is used as PTC, and the condition are: temperature is 60 °C, time is 60 min, H 2 O 2 /sulfur molar ratio (O/S) is 4, the desulfurization rate reaches the maximum (93.3%), and the desulfurization of the real gasoline is also investigated, 87.7% of sulfur contents are removed under optima reaction conditions. The PTC [BPy]HSO 4 can be recycled for five times without significant decrease in activity.

xEt3NHCl·FeCl3 (x = 1.4−1.8) ionic liquids were synthesized by mixing Et3NHCl and anhydrous FeCl3 at 80 °C. These were liquid at room temperature, with low viscosities, and exhibited remarkable abilities in effective desulfurization of thiophene in n-octane and fluid catalytic cracking (FCC) gasoline. Among them, 1.6Et3NHCl·FeCl3 showed the highest sulfur removal. The anionic species FeCl4− existed in 1.6Et3NHCl·FeCl3 ionic liquid, as detected by electrospray ionization−mass spectrometry (ESI−MS), and the ionic liquid was stable in air and moisture. Sulfur-free (

Photochemical oxidative desulfurization of thiophene with tetrabutylammonium bromide (TBAB) as phase transfer catalyst was studied. The effects of the TBAB addition and pH on the desulfurization yield of thiophene were investigated. The cycle model of desulfurization of thiophene with TBAB was proposed. The results show that the desulfurization yield of thiophene in n-octane is 80.6% for a 2-hr photoirradiation under the conditions of air flow at 150 mL/min, V (n-octane):V (water) = 1:1, pH = 12, and 0.1 g of TBAB as catalyst. The photooxidation kinetics of thiophene is first-order with rate constant of 0.5702 hr−1 and half-life of 1.22 hr.

Hydrophilic Ti-MCM-41 was modified by alkylsilyl groups using n-octadecyltrichlorosilane as the precursor, yielding an amphiphilic molecular sieve denoted as OTS-Ti-MCM-41. The sample retained mesoporous structure and morphology, as confirmed by XRD, N2 adsorption–desorption, and SEM. The presence of surface alkylsilyl groups was confirmed by infrared spectroscopy. The amphiphilic OTS-Ti-MCM-41 located at the boundary between aqueous and organic phases acted as a phase-boundary catalyst for the photooxidation of dibenzothiophene (DBT) without the need of adding a co-solvent to drive liquid–liquid phase transfer. With H2O2 as the oxidant, the conversion of DBT on OTS-Ti-MCM-41 was up to 98% at 2 h, much higher than that on Ti-MCM-41. When air was used instead of H2O2 as the oxidant, the conversion of DBT on OTS-Ti-MCM-41 was up to 85% at 2 h. Hydrophilic Ti-MCM-41 was modified by alkylsil groups using n-octadecyltrichlorosilane as the precursor. The resulting OTS-Ti-MCM-41 sample located at the boundary between aqueous and organic phases acted as a phase-boundary catalyst for the photooxidation of dibenzothiophene (DBT).

Oxidative desulfurization (ODS) of dibenzothiophene (DBT) in n-octane with hydrogen peroxide/acetic acid using a quaternary ammonium coordinated ionic liquid (IL) (C4H9)4NBr · 2C6H11NO as catalytic solvent has been studied. The ODS mechanism by coordinated ionic liquid [(C4H9)4NBr · 2C6H11NO] was also carried out. The sulfur-containing compounds in model oil were extracted into ionic liquid phase and oxidized to their corresponding sulfones by H2O2. The effect factors for desulfurization of model oil were investigated in detail by means of monofactorial and orthogonal experiments (L16(4)4). The results showed that the desulfurization efficiency of model oil could reach 98.6% under the optimal conditions of oxidation time, oxidation temperature, molar ratio of H2O2/sulfur (O/S), and volume ratio of model oil to coordinated ionic liquid were 30 min, 50°C, 16, and 1, respectively. The influences to the desulfurization efficiency of DBT decreased in the following order: volume ratio of model oil to c...

Bronsted acid ionic liquid, N-methyl-pyrrolidonium tetrafluoroborate ([Hnmp]BF4), was employed as an extractant and a catalyst to remove dibenzothiophene (DBT) from model oil in the presence of H2O2. The kinetics and mechanism of DBT oxidation by [Hnmp]BF4 and H2O2 were proposed. DBT could be effectively removed from the oil phase by this process. Most of the oxidative products were in the ionic liquid phase for their higher polar property without additional extraction by solvent. The room-temperature ionic liquid [Hnmp]BF4 could be recycled 7 times without a significant decrease in the desulfurization activity.

For the insolubility of binary phase system of oxidative desulfurization, quaternary ammonium salts as phase-transfer catalysts have been applied to enhance the reaction. To investigate the mechanism, nine catalytic systems were carried out. The results showed that the reaction was of pseudo-first-order in phase-transfer catalyst and substrate of organosulfur, and slightly influenced by the stirring rate documented the reaction was chemical controlled. In the oxidant anion [RCOOO−] transfer process, there was an ion-pair [Q+ROOO−] formed. To clarify the catalytic behavior of phase-transfer catalyst in the liquid-liquid phase system, oxidant anion transfer, interfacial tension and the activity of anion were exploited. It is shown that ion-pair [(C4H9)4N+RCOOO−] could be transferred from aqueous to organic phase, and catalyze the oxidative reaction best. Dibenzothiophene (with larger electrical density) was easier to be removed than thiophene, and the desulfurization rate of dibenzothiophene by tet...

Photocatalytic oxidation of dibenzothiophene (DBT) using TiO2-loaded bamboo charcoals (BC) prepared by wet impregnation was studied. Results obtained here can be used as the reference for evaluating reactions in hydrocarbons, which aims at the development of an oxidative desulfurization process for fuel oils. Technological conditions (the amount of photocatalysts, hydrogen peroxide, and TiO2 loading) were also investigated in detail. The results show that TiO2/BC improves the dispersed degree of TiO2 catalyst, which shows a better photocatalytic performance than pure TiO2. We also found a special characterization of TiO2/BC, it can locate just at the oil–water phase boundary. The oxidation proceeds in the oil phase and most of the oxidation products transfer to water phase, resulting in the successive removal of DBT from the n-octane phase without additional extraction by solvent. In addition, kinetics parameters of the photocatalytic oxidation of DBT were measured and calculated. The result shows the kinetics of photocatalytic oxidation of DBT is first order.

Photocatalytic oxidation of dibenzothiophene with hydrogen peroxide using Ti-containing zeolite (TS-1) as photocatalyst at ultraviolet lamp irradiation has been studied. The effect of the amount of photocatalyst and hydrogen peroxide concentration were investigated in detail. Optimal photocatalyst amount and hydrogen peroxide concentration were obtained at amounts of near 0.1 g/10 mL and 3 mL/10 mL, respectively. The oxidation proceeds in the oil phase and most of the oxidation products transfer to water phase, resulting in the successive removal of the dibenzothiophene from the n-octane phase without additional extraction by solvent. Kinetics parameters of the photocatalytic oxidation of DBT were measured and calculated. The result shows the kinetics of photocatalytic oxidation of DBT is first-order. The activity of photocatalyst was not obviously decreased after reuse ×5. Using this photocatalytic oxidation system can effectively reduce the sulfur content in diesel oil. The resulting oil contai...

The degradation of omethoate was conducted using H2O2 as oxidant, TiO2 supported on NaY zeolite as photocatalyst and a 300W lamp as light source. The effect of the calcination temperature of the photocatalyst, the amount of TiO2 loaded on NaY zeolite, the photocatalyst amount, the pH value and the radiation time on the degradation ratio of omethoate were investigated. The results show that TiO2/NaY zeolite photocatalyst prepared by sol-gel method had good photocatalysis. The photocatalytic optimum oxidation conditions of omethoate are as follows: the calcination temperature of the photocatalyst is 550°C,the amount of TiO2 loaded on NaY zeolite is 35.2 wt-%, the amount of photocatalyst is 5 g/L, pH = 8 and the radiation time is 180 min. Under these conditions, the removal ratio of omethoate is up to 93%.

Photochemical oxidation of thiophene in an n-octane/acetonitrile extraction system using O(2) as oxidant was studied. Results obtained here can be used as a reference for desulfurization of gasoline, because thiophene is one of the main components containing sulfur in fluid catalytic cracking gasoline. A 500-W high-pressure mercury lamp was used as a light source for irradiation, and air was introduced by a gas pump to supply O(2). Thiophene dissolved in nopolar n-octane solvent was photodecomposed and removed into the polar acetonitrile phase. The desulfurization rate of thiophene in n-octane was 65.2% under photoirradiation for 5 h under the conditions of air flow at 150 mL min(-1), and V(n-octane):V(acetonitrile) = 1:1. This can be improved to 96.5% by adding 0.15 g Na-ZSM-5 zeolite into the 100-mL reaction system, which is the absorbent for O(2) and thiophene. Under such conditions, the photooxidation kinetics of thiophene with O(2) and Na-ZSM-5 zeolite is first-order with an apparent rate constant of 0.6297 h(-1) and half-time of 1.10 h. The sulfur content can be reduced from 800 microL L(-1) to 28 microL L(-1).