A highly efficient process for producing bulk chemical diethyl maleate is achieved with polyoxometalate ionic liquids from a cleavage lignin aromatic unit with high yield and selectivity, which is ascribed to the intensive synergistic effect between the acidic depolymerization, oxidative aromatic ring cleavage, and in situ esterification. This work offers new insight into the versatile petroleum-based chemical production from renewable resources.

A facile solvent evaporation induced self-assembly (SEISA) strategy was developed to synthesize mesoporous N-doped anatase TiO 2 (SE-meso-TON) using a single organic complex precursor derived in situ from titanium butoxide and ethylenediamine in ethanol solution. After the evaporation of ethanol in a fume hood and subsequent calcinations at 450 C, the obtained N-doped TiO 2 (meso-TON)anatase was of finite crystallite size, developed porosity, large surface area (101 m 2 g À1) and extended light absorption in the visible region. This SE-meso-TON also showed superior photocatalytic activity to the SG-meso-TON anatase prepared via sol-gel synthesis. On the basis of characterization results from XRD, XPS, N 2 adsorption-desorption and ESR, the enhanced visible-light-responsive photocatalytic activity of SE-meso-TON was assigned to its developed mesoporosity and reduced oxygen vacancies. IntroductionMotivated by the discovery of the excellent visible-lightresponse of nitrogen-doped TiO 2 (TiO 2Àx N x , hereaer, TON),various nonmetal dopants (e.g. N, C, S, P, and halogen elements) have been extensively attempted to be doped or codoped into the TiO 2 matrix for narrowing its wide bandgap ($3.2 eV) and thus harvesting visible light. 3 Among those doped TiO 2 materials, TON is more desirable due to its low energy requirement for doping and superb performance in photovoltaic and photocatalytic applications.2,4-7 In practice, the mesoporous TON (meso-TON) is plausible because its large specic surface area (SSA) and developed porosity favour solar energy conversion. 4,8 Despite the fact that enormous advances have been achieved in the control of N-doping level, morphology, crystallite size and crystallinity of TiO 2Àx N x , 9-11 synthesis of mesoporous TiO 2Àx N x (meso-TON) remains a great challenge because the mesoporous structure is prone to collapse during nitriding and crystallization at elevated temperature. 8,12-14Ammonolysis is the most used nitriding technique for preparation of TON, though it occurs above 500 C. 2,10,13 Such a high ammonolysis temperature inevitably destructs the porosity of the primitive meso-TiO 2 , induces phase transition and hampers its applications in thin lm devices.2,10 In order to retain its developed porosity, a few low-temperature methodologies, such as sol-gel, 9 hydrothermal or solvothermal combined with post-nitriding, 10,11 have been developed for preparing meso-TON. In those methodologies, the involved solvent, surfactant template and chemical sources of Ti and N controlled the hydrolysis, nitriding and crystallization processes and thus determined the mesoporosity of the resultant TON. 15,16 In particular, the alternative nitrogen sources to NH 3 , such as NH 4 Cl, 13 urea, 15,17,18 HMT, 19 glycine 16 and thiourea, 20 are plausible for realizing low-temperature nitriding. Solvent evaporation induced assembly (SEISA) has been demonstrated to be an excellent route to prepare meso-TiO 2 thin lms, 12 in terms of its great exibility in handling the synthesis system (solvents, su...

Novel and selective strategies for platform chemical production from renewable biomass are highly attractive in respect to value-added utilization of sustainable resources. In this study, a series of low-cost, commercially available, transition metal carbonates (Zr, Ni, Mg, Zn, and Pb) were investigated for catalytic transfer hydrogenation of levulinate esters to γ-valerolactone (GVL) via the cascade process of Meerwein−Ponndorf−-Verley (MPV) reduction and lactonization reaction. Among the selected catalysts, basic zirconium carbonate is the most active, with the highest turnover frequency (TOF) of 3.1 h −1 and a surface reaction rate of 0.21 mol m −2 h −1 . At 453 K, 3.0 h, and 1.0 MPa N 2 , 100% ethyl levulinate conversion, 96.3% GVL yield, and 91.9% hydrogen donor utilization are observed due to the cooperative effect between acid (M n+ ) and base (−OH) sites. Furthermore, this catalyst shows high recyclability under the optimized conditions, where a satisfactory catalytic activity is shown even after six consecutive runs.

An investigation of the nature of the carbonaceous species deposited upon mordenite by reaction with methanol has been undertaken. The nature of the species has been shown to be a strong function of both temperature and time on stream. Upon reaction at 300 degrees C a range of alkyl and aromatic species, consistent with the development of an active hydrocarbon pool, are evident and time on stream studies have shown that these are developed within 5 min. Upon reaction at 500 degrees C, a narrower range of hydrogen deficient aromatic species is evident. Thermal volatilisation analysis (TVA), not previously applied to the study of coked zeolites, is shown to be complementary to the more commonly applied C analysis, C-13 MAS NMR and TGA techniques

Regeneration of the coked catalyst is an important process of fluid catalytic cracking (FCC) in petroleum refining, however, this process will emit environmentally harmful gases such as nitrogen and carbon oxides. Transformation of N and C containing compounds in industrial FCC coke under thermal decomposition was investigated via TPD and TPO to examine the evolved gaseous species and TGA, NMR and XPS to analyse the residual coke fraction. Two distinct regions of gas evolution are observed during TPD for the first time, and they arise from decomposition of aliphatic carbons and aromatic carbons. Three types of N species, pyrrolic N, pyridinic N and quaternary N are identified in the FCC coke, the former one is unstable and tends to be decomposed into pyridinic and quaternary N. Mechanisms of NO, CO and CO2 evolution during TPD are proposed and lattice oxygen is suggested to be an important oxygen resource. Regeneration process indicates that coke-C tends to preferentially oxidise compared with coke-N. Hence, new technology for promoting nitrogen-containing compounds conversion will benefit the in-situ reduction of NO by CO during FCC regeneration.