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Highlights: [•] Synthesis of the HKUST-1 with mesoporous structure. [•] Exploration of the new application of MOFs materials in uranium removal. [•] Development of a high-efficiency adsorbent for uranium. [Copyright &y& Elsevier]

A hybrid composite Fe 3 O 4 /g-C 3 N 4 -CeO x prepared with Fe(NO 3) 3 , (NH 4) 4 Ce (SO 4) 4 and g-C 3 N 4 as precursors via in situ reduction of Fe (III) to Fe (II) exhibited an efficiently catalytic performance for solvent-free oxidation of styrene using H 2 O 2 oxidant, achieving 92% conversion and 70.0% selectivity to benzaldehyde, as well as excellent reusability. [Display omitted] Fe and Ce incorporated graphic carbon nitride Fe-Ce/g-C 3 N 4 was fabricated with Fe(NO 3) 3 , (NH 4) 4 Ce (SO 4) 4 and g-C 3 N 4 as precursors and its surface composition and structure was identified by XRD, SEM, TEM, FT-IR, XPS, ICP-OES and N 2 adsorption-desorption approach. The results demonstrated that the hybrid composite was constituted with Fe 3 O 4 supported on CeO x , where Fe 3 O 4 crystals were formed by in situ reduction of Fe 3+ through produced NH 3 of g-C 3 N 4 decomposition. The hybrid composite exhibited an efficiently catalytic performance for solvent-free oxidation of styrene to benzaldehyde using H 2 O 2 oxidant with 92% conversion and 70.0% selectivity. The dependence of the catalytic activity on the catalyst preparation conditions and reaction conditions were explored and the reusability of the catalyst was discussed. [ABSTRACT FROM AUTHOR]

A composite catalyst was prepared by impregnation of ZSM-5 in mixture solution of Co(NO 3) 2 , ZrOCl 2 and phosphotungstic acid (PW) and characterized by XRD, FT-IR, UV–vis, XPS, SEM and TEM techniques to confirm its structure and composition. The pre-prepared composite is composed of Co 2 (PO 4)Cl, ZrO 2 , P 2 O 5 and WO 3 crystalline nanoparticles uniformly dispersed on ZSM-5 zeolite. The prepared composite demonstrates effective catalytic function for solvent-free oxidation of toluene into benzaldehyde with H 2 O 2 oxidant, achieving 16.6% conversion and 90% selectivity. The effect of various components composed of the catalyst and reaction conditions on the catalytic function were explored. Moreover, the recovery and reusability of the catalyst were estimated, presenting good reusability. [Display omitted] • Co, Zr and H 3 PW 12 O 40 modified ZSM-5. • Dispersed Co 2 (PO 4)Cl or P 2 O 2 , ZrO 2 and WO 3 nanoparticles. • Efficient catalyst for toluene oxidation. • Guest nanocrystals as synergic active sites. • Higher conversion and selectivity, excellent reusability. [ABSTRACT FROM AUTHOR]

Iron and molybdenum modified phosphotungstates (FeMoPW) were synthesized by reaction of H 3 PW 12 O 40 (PW) with Fe(NO 3) 3.9 H 2 O and (NH 4) 6 Mo 7 O 24.4 H 2 O, followed by calcined, and characterized by XRD, FT-IR, UV–vis, SEM, TEM and XPS to determine the surface composition and structure. The as-prepared FeMoPW was utilized as a catalyst for solvent-free oxidation of styrene with hydrogen peroxide oxidant and it exhibited higher styrene conversion (60%) and high selectivity to benzaldehyde (90%). The FeMoPW catalyst converted styrene into benzaldehyde by synergic effect of FePW and Fe 2 (MoO 4) 3 active sites on the surface. The recovery and reusability of the catalyst were evaluated and excellent reusability was achieved. In addition, in situ adsorptions of styrene and H 2 O 2 on the catalyst surface were conducted and the reaction mechanism via forming styrene oxide, and benzyl alcohol intermediates was proposed. Iron and molybdenum modified phosphotungstates was utilized as a catalyst for solvent-free oxidation of styrene with hydrogen peroxide oxidant, exhibiting higher conversion of styrene with 60% and high selectivity to BzH with 90%. The higher catalytic activity of this catalyst is ascribed to mutual action of components FePW and Fe 2 (MoO 4) 3 crystallines and the reaction mechanism via producing styrene oxide, followed by forming BzOH intermediates is proposed. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] Waste product of oil shale industry was utilized as sorbent for uranium. [•] Hydrotalcite-like compound was synthesized using oil shale ash. [•] Composition, microstructure and absorptive property were investigated. [•] It was an Mg–Al-based hydrotalcite compound with a lamellar morphology. [•] The maximum adsorption capacity toward uranium is 156mg/g at 298K. [ABSTRACT FROM AUTHOR]