Search

Four novel organic–inorganic hybrid compounds based on mono-lanthanide-substituted phosphotungstates, [PW11O39Ln(phen)(H2O)]2·(phen)8·8H3O (1: Ln = Pr; 2: Ln = Gd; 3: Ln = Sm; 4: Ln = La; phen = 1,10-phenanthroline), have been synthesized under hydrothermal conditions and characterized by IR, UV–Vis spectrum, powder XRD, photoluminescence analysis, elemental analysis and X-ray diffraction analysis. Single crystal X-ray analysis reveals that compounds 1–4 are the first N-containing organic ligands functionalized mono-lanthanide-substituted polyoxometalates. The catalytic properties of these compounds were also investigated.

A simple and novel quinoline derivative (QN), based on quinoline-8-carboxaldehyde and 3‑hydroxy-2-naphthoic hydrazide was synthesized. The structure of chemosensor QN was confirmed by X-ray Crystallography. The chemosensor QN as dual chemosensor showed selective fluorescence recognition of Al3+ and colorimetric detection of Fe2+. In the presence of Al3+, the sensor QN generated a noticeable fluorescence enhancement accompanied with obvious color change from colorless to yellowish green. Moreover, QN was successfully used for colorimetric sensing for Fe2+, while the solution color changed from pale yellow to dark green. The detection limit was obtained to be 1.22 × 10−8 mol L−1 for Al3+ and 1.04 × 10−7 mol L−1 for Fe2+. The sensing mechanism of sensor QN toward Al3+ and Fe2+ were investigated by 1H NMR, ESI-MS and IR. Moreover, the coordination modes of QN-Al3+ and QN-Fe2+were confirmed by theoretical calculations.

The catalytic (SBA-15, Ni/SBA-15, Al/SBA-15 and Ni-Al/SBA-15) hydrothermal liquefaction (HTL) of rice straw biomass was examined at different temperature with different amount of catalyst in the presence of different solvents. In comparison with water solvent liquefaction, the bio-oil yield significantly increased under alcoholic solvent (ethanol and methanol). The highest bio-oil yield was observed for water (44.3 wt%) with Ni-Al/SBA-15, while for ethanol (56.2 wt%), and for methanol (48.1 wt%) with, Ni/SBA-15 catalyst. The loading of Ni and Al on SBA-15, the acid strength of the catalyst enhanced. Bio-oils yield were analyzed with the help of GC–MS, FT-IR, NMR, GPC and CHNS. From the GC–MS analysis, the main monomeric phenolic compounds were produced, phenol, 4-ethyl-phenol, 2-methoxy-phenol, 2-methoxy-4-ethyl-phenol and Vanillin. It was observed by CHNS and GPC analysis of the bio-oil, compared to the non-catalytic liquefaction reaction, the catalytic liquefaction reaction promotes the hydrogenation/hydrodeoxygenation and produced lower molecular weight bio-oils.