Catalytic Activity of FeCrNiWMoCoCB Metallic Glass Coatings on a Metal Support in Dye Wastewater Treatment

2018 ◽  
Vol 18 (6) ◽  
pp. 14-19
Author(s):  
A. A. Burkov ◽  
A. V. Zaitsev

Catalytic activity of FeCrNiWMoCoCB metallic glass (MG) coatings deposited on steel 1035 was studied in decomposition of the model solution of methylene blue. Five samples with different compositions and predominantly amorphous structure were synthesized by depositing MG coatings using the electrospark treatment in the crystalline alloy granule medium. The Ra criterion characterizing the coatings roughness was 9 to 14 mm that indicated the considerable area of interaction between MG and methylene blue. The presence of nickel and cobalt but not tungsten and molybdenum in the metallic glass favored an increase in the catalytic activity of the coatings. The best catalytic properties were inherent in the coatings consisted of Fe33Cr8Ni8W8Mo8Co8C16B11which provided a decrease in the activation energy of self-decomposition of methylene blue to one eighth in the presence of hydrogen peroxide. It was shown that the efficiency of this catalytic system could be increased by a factor of 3 upon etching in 30 % HNO3for 380 s due to an increase in the porosity and in the specific surface area of the coating. The suggested approach makes it possible to decrease considerably the prime cost of the catalytic units of the reactor owing to application of one-stage supporting of MG coating on the metals.

2014 ◽  
Vol 955-959 ◽  
pp. 2705-2708
Author(s):  
Qin Fang Lu ◽  
Tao Yang

To improve the utilization rate of visible light in the degradation of the dye wastewater, the supported mesoporous TiO2 catalyst with perlite as the carrier was prepared. The effect of the calcination time and the loading time on the degradation of the methylene blue by the catalyst was analyzed. The result showed that: as the calcination time exceeded 1.5h, the catalyst activity decreased with the calcination time increasing; under the condition of the optimal calcination time of 1.5h, the degradation rate of methylene blue by visible light reached 71.59%; the multi-loading was in favor of increasing the catalyst activity, of which 3-time loading was the optimal.


2020 ◽  
Vol 10 (19) ◽  
pp. 6468-6482 ◽  
Author(s):  
Kaixi Deng ◽  
Lili Lin ◽  
Ning Rui ◽  
Dimitriy Vovchok ◽  
Feng Zhang ◽  
...  

Metal–oxide interactions affect the catalytic properties of Co/CeO2 and can be used to control activity and selectivity.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Nicolaza Pariona ◽  
M. Herrera-Trejo ◽  
J. Oliva ◽  
A. I. Martinez

The peroxidase-like catalytic properties of 2-line ferrihydrite (2LFh) and hematite nanoparticles (NPs) for the degradation of methylene blue (MB) were studied. It is highlighted that the hematite NPs were prepared from the transformation of the metastable 2LFh NPs. It was found that the 2LFh NPs exhibited poor crystallinity with an average size of 5 nm, while the hematite NPs exhibited high crystallinity with an average size ofca. 100 nm. It was found that the total degradation of MB occurred for hematite NPs, while only a maximum degradation of 69% was possible for the 2LFh NPs. The Michaelis–Menten parameters indicated that the hematite NPs present higher catalytic activity than the 2LFh NPs at basic pH. It was found that the ordered surface of the hematite NPs has a stronger effect for the degradation of MB than its low surface area. It was concluded that the crystal planes of the hematite NPs affect the catalytic process more significantly than the high surface area of 2LFh NPs.


2013 ◽  
Vol 749 ◽  
pp. 99-105 ◽  
Author(s):  
Maroš Soldán ◽  
Karol Balog ◽  
Hana Kobetičová

Many industries, such as paper, plastics, food, cosmetics, textile, etc., use dyes in order to colour their products. The presence of these dyes in water, even at very low concentrations, is highly visible and undesirable. Since some of these dyes are toxic in nature, their removal from the industrial effluents is a major environmental problem. The objective of this work is to verify the catalytic activity of waste from metal production namely waste from aluminium production red mud for removal of methylene blue. This waste is still dumped on dumping ground and may be a potential environmental problem.


2019 ◽  
pp. 96-105
Author(s):  
M. L. Shishkova ◽  
N. V. Yakovleva

The paper considers science and engineering aspects of catalytically active compositions creation as regards immobilized catalysts for reforming hydrocarbon raw materials into hydrogen fuel. The authors investigate synthesis of catalytic powder mixtures and manufacturing of functional coatings by supersonic cold gas dynamic spraying. Research results in the field of creation of catalysts for steam conversion of methane to hydrogenous fuel on the metal support (Cr15Al15 tape support) are given. Composite powder mixtures (Ni–Al–Al(OH)3– Ca(OH)2–Mg(OH)2) were used as starting materials.


1979 ◽  
Vol 44 (4) ◽  
pp. 1015-1022 ◽  
Author(s):  
Viliam Múčka

The catalytic properties of two-component catalyst nickel oxide-cadmium oxide with the proportions of the components covering the whole composition region 0-100% were examined by studying the decomposition of hydrogen peroxide in aqueous solution on it. In the range 0-25 mol.% CdO, cadmium oxide is found to affect infavourably the ability of nickel oxide to chemisorb oxygen. The amount of the chemisorbed oxygen increases several times on gamma irradiation of the samples. The effect of cadmium oxide on the catalytic activity of the system shows up in fresh samples only indirectly via the changed amount of the oxygen chemisorbed. In older samples the initial catalytic activity of the system is changed, which can be explained based on the concept of bivalent catalytic centres in terms of the co-action of the catalytic centres of the two oxides, which are in equilibrium. The irradiation of the system under study speeds up the processes leading to the establishing of this equilibrium which is thermally very stable, and results in a substantial increase of the catalytic activity of the samples investigated.


1988 ◽  
Vol 53 (8) ◽  
pp. 1636-1646 ◽  
Author(s):  
Viliam Múčka ◽  
Kamil Lang

Some physical and catalytic properties of the two-component copper(II)oxide-chromium(III)oxide catalyst with different content of both components were studied using the decomposition of the aqueous solution of hydrogen peroxide as a testing reaction. It has been found that along to both basic components, the system under study contains also the spinel structure CuCr2O4, chromate washable by water and hexavalent ions of chromium unwashable by water. The soluble chromate is catalytically active. During the first period of the reaction the equilibrium is being established in both homogeneous and heterogeneous catalytic systems. The catalytic activity as well as the specific surface area of the washed solid is a non-monotonous function of its composition. It seems highly probable that the extreme values of both these quantities are not connected with the detected admixtures in the catalytic system. The system under study is very insensitive with regard to the applied doses of gamma radiation. Its catalytic properties are changed rather significantly after the thermal treatment and particularly after the partial reduction to low degree by hydrogen. The observed changes of the catalytic activity of the system under study are very probably in connection with the changes of the valence state of the catalytically active components of the catalyst.


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 88
Author(s):  
Diana García-Pérez ◽  
Maria Consuelo Alvarez-Galvan ◽  
Jose M. Campos-Martin ◽  
Jose L. G. Fierro

Catalysts based on zirconia- and alumina-supported tungsten oxides (15 wt % W) with a small loading of platinum (0.3 wt % Pt) were selected to study the influence of the reduction temperature and the nature of the support on the hydroisomerization of n-dodecane. The reduction temperature has a major influence on metal dispersion, which impacts the catalytic activity. In addition, alumina and zirconia supports show different catalytic properties (mainly acid site strength and surface area), which play an important role in the conversion. The NH3-TPD profiles indicate that the acidity in alumina-based catalysts is clearly higher than that in their zirconia counterparts; this acidity can be attributed to a stronger interaction of the WOx species with alumina. The PtW/Al catalyst was found to exhibit the best catalytic performance for the hydroisomerization of n-dodecane based on its higher acidity, which was ascribed to its larger surface area relative to that of its zirconia counterparts. The selectivity for different hydrocarbons (C7–10, C11 and i-C12) was very similar for all the catalysts studied, with branched C12 hydrocarbons being the main products obtained (~80%). The temperature of 350 °C was clearly the best reduction temperature for all the catalysts studied in a trickled-bed-mode reactor.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4508
Author(s):  
Zeinab Mcheik ◽  
Ludovic Pinard ◽  
Joumana Toufaily ◽  
Tayssir Hamieh ◽  
T. Jean Daou

Hierarchical MOR-type zeolites were synthesized in the presence of hexadecyltrimethylammonium bromide (CTAB) as a porogen agent. XRD proved that the concentration of CTAB in the synthesis medium plays an essential role in forming pure hierarchical MOR-type material. Above a CTAB concentration of 0.04 mol·L−1, amorphous materials are observed. These hierarchical mordenite possess a higher porous volume compared to its counterpart conventional micrometer crystals. Nitrogen sorption showed the presence of mesoporosity for all mordenite samples synthesized in the presence of CTAB. The creation of mesopores due to the presence of CTAB in the synthesis medium does not occur at the expense of zeolite micropores. In addition, mesoporous volume and BET surface seem to increase upon the increase of CTAB concentration in the synthesis medium. The Si/Al ratio of the zeolite framework can be increased from 5.5 to 9.1 by halving the aluminum content present in the synthesis gel. These synthesized hierarchical MOR-type zeolites possess an improved catalytic activity for n-hexane cracking compared to large zeolite crystals obtained in the absence of CTAB.


2021 ◽  
Author(s):  
Chen-Lin Luo ◽  
Chu-Xing Hu ◽  
Ping Shang ◽  
Guan-Zhao Wen ◽  
Jia-Jun Zhu ◽  
...  

A series of heteroleptic Cu(i) complexes were precisely synthesized using different bipyridine and diphosphine ligands. These complexes exhibited fluorescence sensing towards silver ions and high catalytic activity towards the CuAAC reaction.


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