Promotional role of La addition in the NO oxidation performance of a SmMn2O5 mullite catalyst

2016 ◽  
Vol 6 (14) ◽  
pp. 5580-5589 ◽  
Author(s):  
Zijian Feng ◽  
Jianqiang Wang ◽  
Xiao Liu ◽  
Yanwei Wen ◽  
Rong Chen ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Maximum Activity ◽  
No Oxidation ◽  
Precipitation Method ◽  
Oxidation Performance ◽  
La Substitution ◽  
La Addition ◽  
Co Precipitation

A series of LaxSm1−xMn2Oδ (x = 0, 0.1, 0.3, 0.5) catalysts were synthesized through a co-precipitation method. The catalytic activity for NO oxidation was enhanced with La substitution, and the maximum activity was achieved at x = 0.3.

Role of Ni2+ Ions in Magnetite Nano-particles Synthesized by Co-precipitation Method

2016 ◽  
Vol 30 (5) ◽  
pp. 1177-1186 ◽  
Author(s):  
Safia Anjum ◽  
Hafsa Saleem ◽  
Khalid Rasheed ◽  
Rehana Zia ◽  
Saira Riaz ◽  
...  
Keyword(s):  
Nano Particles ◽  
Precipitation Method ◽  
Co Precipitation

High Catalytic Activity and Stability of Hexaaluminate Catalysts for N2O Decomposition

2013 ◽  
Vol 320 ◽  
pp. 665-669
Author(s):  
Chao Zhang ◽  
Yong Ji Song ◽  
Feng Hua Shi ◽  
Cui Qing Li ◽  
Hong Wang
Keyword(s):  
Catalytic Activity ◽  
Decomposition Reaction ◽  
Precipitation Method ◽  
High Catalytic Activity ◽  
Structure And Properties ◽  
Active Components ◽  
Co Precipitation ◽  
Hexaaluminate Catalysts

In this paper, hexaaluminate oxides LaMAl12O19-σwere prepared by using M=Cu ,Ce and Zn as active components to substitute Al in the hexaaluminate lattice by co-precipitation method. The structure and properties of LaMAl11O19-σcatalyst was characterized with XRD and BET. The results showed LaCuAl11O19-σexhibited significant high catalytic activity for the decomposition reaction of N2O. Under the simulated in situ condition, LaCuAl11O19-σalso indicated significant catalytic activity and stability, with N2O conversion of 90% at 635°C.

Non-Thermal Plasma Assisted Catalytic Oxidation NO over Mn-Ni-Ox Catalysts at Low-Temperature

2011 ◽  
Vol 383-390 ◽  
pp. 3092-3098 ◽  
Author(s):  
Kai Li ◽  
Xiao Long Tang ◽  
Hong Hong Yi ◽  
Ping Ning ◽  
Zhi Qing Ye ◽  
...  
Keyword(s):  
Low Temperature ◽  
Catalytic Oxidation ◽  
Thermal Plasma ◽  
Space Velocity ◽  
Input Voltage ◽  
No Oxidation ◽  
Precipitation Method ◽  
Non Thermal Plasma ◽  
High Space ◽  
Co Precipitation

Mn-Ni-Ox catalyst was prepared by the co-precipitation method. The most active catalysts were obtained with a molar Ni/ (Mn+Ni) ratio of 0.1. The results showed that over this catalyst, NO oxidation conversion reached 59% at 125°C and 50% at 150°C with a high space velocity of 35000h-1. Their surface properties were evaluated by means of scanning electron microscopy (SEM). The process of non-thermal plasma-assisted catalytic oxidation of NO under low-temperature was studied. And the NO conversion could reach 80% with the non-thermal plasma-assisting at 150°C when the input voltage was 30V. The increasing activities at low temperature（50~175°C）were more apparently higher than high temperature by plasma. And the low-temperature catalytic activity of the catalyst was increased with the increase of the input voltage.

A highly-efficient La–MnOx catalyst for propane combustion: the promotional role of La and the effect of the preparation method

2016 ◽  
Vol 6 (23) ◽  
pp. 8222-8233 ◽  
Author(s):  
Yujie Xie ◽  
Yun Guo ◽  
Yanglong Guo ◽  
Li Wang ◽  
Wangcheng Zhan ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Preparation Method ◽  
Deep Oxidation ◽  
Precipitation Method ◽  
Propane Combustion ◽  
Highly Efficient ◽  
Excellent Activity ◽  
Co Precipitation

The La0.4–MnOx catalyst prepared by using the co-precipitation method exhibited excellent activity and thermal stability for propane deep oxidation.

Carbodiimide for Covalent α-Amylase Immobilization onto Magnetic Nanoparticles

2017 ◽  
Vol 16 (05n06) ◽  
pp. 1750015 ◽  
Author(s):  
Zeinab Mortazavi Milani ◽  
Razieh Jalal ◽  
Elaheh K. Goharshadi
Keyword(s):  
Residual Activity ◽  
Maximum Activity ◽  
Covalent Attachment ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Operational Conditions ◽  
Transmission Electron ◽  
Repeated Batch ◽  
Repeated Use ◽  
Co Precipitation

Covalent cross-linking of enzymes to magnetite (Fe3O4) nanoparticles (MNPs) is one of the useful enzyme immobilization methods which provides repeated use of the catalyst, facilitates enzyme separation from the reaction mixture, and sometimes improves biocatalysts stability. The aim of this study was to immobilize [Formula: see text]-amylase onto MNPs via covalent attachment using carbodiimide (CDI) molecules. MNPs were synthesized by the co-precipitation method. The size and the structure of the particles were characterized by X-ray diffraction and transmission electron microscopy. The effects of different operational conditions of direct [Formula: see text]-amylase binding on MNPs in the presence of CDI were investigated by using the shaking method. Fourier transform infrared spectroscopy was used to confirm the success of immobilization. The optimum conditions and catalytic properties of immobilized [Formula: see text]-amylase were also evaluated. The efficiency of immobilization and the residual activity of the immobilized [Formula: see text]-amylase were dependent on the mass ratio of MNPs: CDI: [Formula: see text]-amylase and the immobilization temperature. The optimum pH for the free and immobilized amylase was 6. The free and immobilized [Formula: see text]-amylase showed maximum activity at 20[Formula: see text]C and 35[Formula: see text]C, respectively. The immobilized [Formula: see text]-amylase was more thermostable than the free one. The retained activity for free [Formula: see text]-amylase after 19 storage days was 57.7% whereas it was 100% for the immobilized [Formula: see text]-amylase. In repeated batch experiments, the immobilized [Formula: see text]-amylase retained a residual activity of 45% after 11 repeated uses. The [Formula: see text] and [Formula: see text] values for the immobilized enzyme were larger than those of the free enzyme. The immobilization of [Formula: see text]-amylase on MNPs using CDI improves its stability and reusability.

Study on the Preparation of Nano Fe3O4 Powder and its Properties

2012 ◽  
Vol 178-181 ◽  
pp. 562-565
Author(s):  
Rui Cui Liu ◽  
Fu Yi Jiang ◽  
Zi Quan Liu
Keyword(s):  
Catalytic Activity ◽  
Rhodamine B ◽  
Catalytic Degradation ◽  
Model Reaction ◽  
Iron Chloride ◽  
Precipitation Method ◽  
Photo Catalytic Activity ◽  
Powder Samples ◽  
Nano Fe3o4 ◽  
Co Precipitation

The experiment used iron chloride, iron dichloride and other agents as the main resources to prepare the nano Fe3O4 powder by co-precipitation method. Magnets were used to test the magnetism of the prepared nano Fe3O4 powder samples. And the photo-catalytic degradation of rhodamine B solution was used as the model reaction to test the photo-catalytic activity of the prepared nano Fe3O4 powder. The results showed that the prepared nano Fe3O4 powder samples had good magnetism but low photo-catalytic activity.

scholarly journals Poly(catechol) modified Fe3O4 magnetic nanocomposites with continuous high Fenton activity for organic degradation at neutral pH

2021 ◽  
Author(s):  
Yani Hua ◽  
Chuan Wang ◽  
Sha Wang ◽  
Juan Xiao
Keyword(s):  
Catalytic Activity ◽  
Fenton Reaction ◽  
Organic Molecules ◽  
Precipitation Method ◽  
Organic Degradation ◽  
Redox Pair ◽  
Iron Leaching ◽  
Acidic Conditions ◽  
Ph Range ◽  
Co Precipitation

Abstract Fe3O4 magnetic nanoparticles (MNPs) have been widely used as a recyclable catalyst in Fenton reaction for organic degradation. However, the pristine MNPs suffer from the drawbacks of iron leaching in acidic conditions as well as the decreasing catalytic activity of organic degradation at a pH higher than 3.0. To solve the problems, Fe3O4 MNPs were modified by poly(catechol) (Fe3O4/PCC MNPs) using a facile chemical co-precipitation method. The poly(catechol) modification improved both the dispersity and the surface negative charges of Fe3O4/PCC MNPs, which are beneficial to the catalytic activity of MNPs for organics degradation. Moreover, the poly(catechol) modification enhanced the efficiency of Fe(II) regeneration during Fenton reaction due to the acceleration of Fe(III) reduction by the phenolic/quinonoid redox pair. As a result, the Fenton reaction with Fe3O4/PCC MNPs could efficiently degrade organic molecules, exampled by methylene blue (MB), in an expanded pH range between 3.0 and 10.0. In addition, Fe3O4/PCC MNPs could be reused up to 8 cycles for the MB degradation with negligible iron leaching of lower than 1.5 mg L-1. This study demonstrated Fe3O4/PCC MNPs are a promising heterogeneous Fenton catalysts for organic degradation.

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