Search results for " Catalyst"
showing 10 items of 292 documents
Modelling wet-air oxidation of phenol in a trickle-bed reactor using active carbon as a catalyst
2016
Cu-B alloy - analysis of use possibility as fuel cell cathode catalyst
2016
In recent years there has been a development of non-conventional and renewable sources of energy. One such sources of energy are fuel cells. Fuel cells are ecological and high efficiency sources of electric energy. However, the use of fuel cells on a large scale is limited, mainly by the high cost of catalysts. Platinum is most commonly used as the catalyst. But due to the high price of platinum there’s a need for finding other catalysts. Replacement of platinum will contribute to the fast development of green energy sources. This paper presents a study of possibility of using Cu-B alloy as catalyst for oxygen electrode in fuel cells. Researches were done in glass vessel, on a copper electr…
Electricity Production from Yeast Wastewater in Membrane-Less Microbial Fuel Cell with Cu-Ag Cathode
2023
Wastewater has high potential as an energy source. Therefore, it is important to recover even the smallest part of this energy, e.g., in microbial fuel cells (MFCs). The obtained electricity production depends on the process rate of the electrodes. In MFC, the microorganisms are the catalyst, and the cathode is usually made of carbon material (e.g., with the addition of Pt). To increase the MFC efficiency (and reduce costs by reducing use of the noble metals), it is necessary to search the new cathode materials. In this work, the electricity production from yeast wastewater in membrane-less microbial fuel cells with Cu-Ag cathode was analyzed. In the first place, the measurements of the sta…
Wastewater treatment and electricity production in a microbial fuel cell with Cu–B alloy as the cathode
2019
The possibility of wastewater treatment and electricity production using a microbial fuel cell with Cu&ndash
Experimental observation of Electronic Metal support interaction: investigation of Au/Ceria catalysts by HERFD–XANES
2015
In this paper we report the result of a recent experiment of high resolution XANES (HERFD-XANES) which evidenced this modification suggesting that gold clusters with very similar size can have a modified electronic structure (the empty d-Density-of-states) when they are deposited on ceria and titania oxide
Effect of hydrogen on the ethylene polymerization process over Ziegler–Natta catalysts supported on MgCl2(THF)2. I. Studies of the chain‐transfer rea…
2001
The effect of hydrogen on the molecular weight of polyethylene obtained over vanadium catalysts (based on VCl4 and VOCl3) supported on MgCl2(THF)2 was studied and the results were compared to those obtained for similar titanium catalysts. It was confirmed that the dependencies of the transfer reaction on the hydrogen concentration are a half‐order in all investigated systems. However, the transition metal of the catalytic site affects the ratio of the transfer rate with hydrogen to the propagation rate (ktr,H/kp) and the results showed that hydrogen is a more effective agent of polyethylene molecular weight control in vanadium‐based systems as compared to the titanium catalyst.
Transversal competences and character education in Latvia: needs analysis report
2018
The national report “Transversal competences and character education in Latvia: Needs analysis report” is a part of the transnational intellectual output 1 “Needs analysis report” elaborated within the Erasmus+ project “Supporting teachers for developing intra-personal competences and character education at school (ARETE CATALYST)”, 2017-1-LV01-KA201-035435. The research report is structured in four parts as follows: 1) A detailed description of transversal competences and character education in Latvia; 2) Case studies of best practices in Latvia; 3) Benchmarking of transversal competences and character education in UK and USA; 4) Developing pupils’ intrapersonal competencies and character …
Effect of Pre-Reduction on the Properties and the Catalytic Activity of Pd/Carbon Catalysts: A Comparison with Pd/Al2O3
2013
The effect of pre-reduction in solution with chemical reagents on the catalytic performance and catalyst properties of Pd/carbon catalysts was systematically investigated with a multitechnique approach. The results are critically discussed in comparison to those recently obtained on analogous Pd/alumina catalysts. It was proved that the Pd phase on the carbon surface is characterized by a high mobility, opposite to what occurs on alumina. As a result, the Pd particles on carbon aggregate together during pre-reduction, with a consequent decrease in available metal surface. Pd particles remain aggregated also in reaction conditions; the decreased Pd dispersion negatively affects the catalyst …