A superparamagnetic graphene oxide/Fe₃O₄/l-proline nano hybrid that was obtained from the non-covalent immobilization of l-proline on graphene oxide/Fe₃O₄ nanocomposite was used as a new magnetically separable catalyst for the efficient synthesis of 4,4'-(arylmethylene)bis(1H-pyrazol-5-ol) derivatives. The prepared heterogeneous catalyst was characterized using FTIR, TGA, DTG, XRD, TEM, SEM, an...

A simple column electrode, S-CE, with a glassy carbon fibers working electrode stuffed into a Teflon tube was developed. The current-potential curves for the reductions of [Fe(CN)(6)](3-) and Fe(3+) observed at the S-CE were analyzed based on a theory for those at an ordinary column electrode. A quantitative electrolysis was performed at the S-CE rapidly within 20 s. An accurate and precise cou...

An ~1:1 mixture of ferrihydrite and nanocrystalline akaganeite (β-FeOOH; 10–15 nm) was incubated with Shewanella putrefaciens (strain CN32) under anoxic conditions with lactate as an electron donor and anthraquinone-2,6-disulfonate (AQDS) as an electron shuttle. The incubation was carried out in a 1,4-piperazinediethanesulfonic acid (PIPES)-buffered medium, without PO4 at circumneutral pH. Iron...

The SiO2 supported cobalt-iron nano catalysts were prepared by the sol-gel method. This research investigated the effects of (Co/Fe) wt.%, different Co/Fe ratio at different temperature and loading of KCl wt.% for Fisher-Tropsch synthesis (FTS). The results were showed that the catalyst containing 50 wt.% (Co/Fe)/SiO2 (Co/Fe ratio is 70/30) which promoted with 0.6 wt.% KCl is an optimal nano ca...

The physical state of the catalyst and its impact on the growth of single-walled carbon nanotubes (SWNTs) is the subject of a long-standing debate. We addressed it here using in situ Raman spectroscopy to measure Fe and Ni catalyst lifetimes during the growth of individual SWNTs across a wide range of temperatures (500-1400 °C). The temperature dependence of the Fe catalyst lifetimes underwent ...

Terminal iron nitrides (Fe≡N) have been proposed as intermediates of (bio)catalytic nitrogen fixation, yet experimental evidence to support this hypothesis has been lacking. In particular, no prior synthetic examples of terminal Fe≡N species have been derived from N2. Here we show that a nitrogen-fixing Fe-N2 catalyst can be protonated to form a neutral Fe(NNH2) hydrazido(2-) intermediate, whic...

The intensive human activities in chemical industry and environmental purification urge the development of advanced protocols for green production and waste management. In environmental science, developing highly efficient and environmentally-friendly catalytic materials and systems are very favourable approaches to green chemical synthesis and remediation of contaminated air, soil, and wastewa...

Carbon nanotubes (CNTs) were prepared by the catalytic chemical vapor deposition of C2H2 at 550°C in 120 minutes using nanoparticles of Ni-Ce-Zr mixed oxides. The CNTs were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and Raman spectroscopy. The results revealed that CNTs with diameter of about 45 nm are o...

Catalytic wet air oxidation (CWAO) is one of the most economical and environmental-friendly advanced oxidation process. It makes a promising technology for the treatment of refractory organic pollutants in industrial wastewaters. Various heterogeneous catalysts including noble metals and metal oxides have been extensively studied to enhance the efficiency of CWAO. The present review is concerne...

In this paper, conventional SAPO-34 and Cerium Hierarchical SAPO-34 zeolites are synthesized using a hydrothermal method for methanol-to-propylene (MTP) reaction. The Ce-H-SAPO-34 catalyst shows a slightly larger crystal size, bimodal pore size distribution (microporous and mesoporous) and lower surface acidity compared to conventional SAPO-34 catalysts. According to these physicochemical prope...