Transformations of Supported Heteropoly Compounds in Oxidative Conversion of Alkanes

2010 ◽  
Vol 1279 ◽  
Author(s):  
Svetlana A. Tungatarova
Keyword(s):  
Water Vapor ◽  
Heteropoly Compound ◽  
Heteropoly Compounds ◽  
Oxidation Reactions ◽  
Oxidative Conversion ◽  
Structural Conversion ◽  
New Findings ◽  
Actual Operation ◽  
Partial Oxidation Reactions ◽  
The Stability

AbstractDynamics of structural transformation of supported heteropoly compound was investigated by IR-spectroscopy, XRD, TPR, and TPO methods. The 15-30 wt.% H3PMo12O40 and H3PV2Mo10O40, supported on SiO2 catalysts were investigated in process under various conditions by interaction with O2 (air) in the presence of water vapor, H2, alkane in TPR regime, O2 in TPO regime (298-1273K) and H2O (298, 923K). The rank of reversible structural conversion of supported heteropoly compounds was established under influence of temperatureand medium. These new findings of reversible structural cycle explains the stability of the 12th series Mo heteropoly compounds supported on Si-containing carrier at high temperatures (873-1073K) which is close to the actual operation temperatures of the partial oxidation reactions and oxidative dehydrogenation of alkanes.

Dynamic Performance of High-Speed Electric Multiple Unit within Multi-Body System Simulation

2019 ◽  
Vol 12 (4) ◽  
pp. 339-349
Author(s):  
Junguo Wang ◽  
Daoping Gong ◽  
Rui Sun ◽  
Yongxiang Zhao
Keyword(s):  
High Speed ◽  
Rapid Development ◽  
Dynamic Performance ◽  
Body System ◽  
High Speed Railway ◽  
Evaluation Indexes ◽  
Actual Operation ◽  
Multiple Unit ◽  
The Stability ◽  
Multi Body

Background: With the rapid development of the high-speed railway, the dynamic performance such as running stability and safety of the high-speed train is increasingly important. This paper focuses on the dynamic performance of high-speed Electric Multiple Unit (EMU), especially the dynamic characteristics of the bogie frame and car body. Various patents have been discussed in this article. Objective: To develop the Multi-Body System (MBS) model of EMU, verify whether the dynamic performance meets the actual operation requirements, and provide some useful information for dynamics and structural design of the proposed EMU. Methods: According to the technical characteristics of a typical EMU, a MBS model is established via SIMPACK, and the measured data of China high-speed railway is taken as the excitation of track random irregularity. To test the dynamic performance of the EMU, including the stability and safety, some evaluation indexes such as wheel-axle lateral forces, wheel-axle lateral vertical forces, derailment coefficients and wheel unloading rates are also calculated and analyzed in detail. Results: The MBS model of EMU has better dynamic performance especially curving performance, and some evaluation indexes of the stability and safety have also reached China’s high-speed railway standards. Conclusion: The effectiveness of the proposed MBS model is verified, and the dynamic performance of the MBS model can meet the design requirements of high-speed EMU.

scholarly journals Rust Conversion Performance of Phosphoric Acid-Gallic Acid in Vinyl Chloride Acrylic Emulsion

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 152
Author(s):  
Xin Wang ◽  
Qingjun Zhu ◽  
Xiangju Liu ◽  
Baorong Hou
Keyword(s):  
Phosphoric Acid ◽  
Gallic Acid ◽  
Vinyl Chloride ◽  
Salt Spray ◽  
Corrosion Current ◽  
Oxidation Reactions ◽  
Acrylic Emulsion ◽  
Conversion Performance ◽  
The Stability ◽  
Iron Complexation

This work studied the application of phosphoric acid-gallic acid in vinyl chloride acrylic emulsion and its rust conversion performance. The increase of phosphoric acid affected the stability of the system, leading to the rapid precipitation of flocculent precipitation. Rust conversion coating (RCC) showed the best synergistic conversion effect when gallic acid (GA) was 0.2 wt.% and phosphoric acid (PA) was 2 wt.%. XRD and FTIR analysis show that the components of adherent rust (AR) are α-FeOOH, γ-FeOOH and Fe3O4. The conversion products are ferric phosphate (FP) and ferric gallate (FG). The RCC can effectively treat the rusted steel (RS) produced by simulated marine atmospheric corrosion. The corrosion current density was reduced by three orders of magnitude, the adhesion reached 2.75 MPa, and the salt spray corrosion resistance was 20 days. The results of Raman, XPS, SEM and EDS show that the ionic dissolution of iron, complexation and further oxidation reactions occur at the interface between the adherent rust and the RCC. After rust conversion treatment, unreacted rust (UR) affects the further improvement of adhesion strength and anti-corrosion performance.

scholarly journals Efficiency of using heteropoly compounds of the type (NH4)2[Co(H2O)4]2[Mo8O27]∙6H2O as catalysts for the production of ethylene

2019 ◽  
Vol 60 (11) ◽  
pp. 85-92
Author(s):  
Nikita A. Panurin ◽  
◽  
Natalya Yu. Isaeva ◽  
Ekaterina B. Markova ◽  
Tatiana F. Sheshko ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Catalyst Deactivation ◽  
Coke Formation ◽  
Fluorescence Analysis ◽  
Heteropoly Compound ◽  
Cascade Reactions ◽  
Environmental Benefits ◽  
Heteropoly Compounds ◽  
X Ray ◽  
Cell Parameters

Carrying out heterogeneous acid catalysis with the use of heteropoly compounds has received considerable attention due to the great economic and environmental benefits. In spite of this, its industrial application is limited as there are difficulties in catalyst regeneration (settling) caused by its relatively low thermal stability. The aim of present work was to search and select catalysts related to the class of heteropoly compounds for propane cracking, to test the selectivity of the prosses as well as to discuss possible approaches for solving the problem of catalyst deactivation, that can contribute to achieve stable characteristics of solid heteropoly catalysts. Among these approaches are: the development of new catalysts with high thermal stability, the modification of catalysts to promote coke combustion, the inhibition of coke formation on heteropoly compound catalysts during the process, carrying out the reactions in supercritical media and also the cascade reactions using a multifunctional heteropoly catalyst. The obtained catalyst was also studied by physicochemical methods to get deep knowledge about which features of these compounds influence on the catalytic activity. A highly active and selective catalyst for ammonium octomolybdenocobaltate(II) ammonium (NH4)2[Co(H2O)4]2[Mo8O27]∙6H2O was synthesized for cracking associated petroleum gases. The qualitative, quantitative, and structural composition as well as the specific surface area of the obtained catalyst was established by the methods of X-ray diffraction, X-ray phase and fluorescence analysis. It was revealed that ammonium octomolybdenocobaltate(II) crystallizes in a triclinic syngony with cell parameters: а = 8.6292(9) Å b = 9.4795(10) Å c = 12.2071(13) Å α = 104.326(2)° β = 109.910(2)° γ = 100.820(2)°.

Ti-MWW Synthesis and Catalytic Applications in Partial Oxidation Reactions

2010 ◽  
Vol 53 (7-10) ◽  
pp. 470-478 ◽  
Author(s):  
Tae-Kyung Kim ◽  
Seung-Tae Yang ◽  
Dong Ryul Park ◽  
In Kyu Song ◽  
Kwang-Eun Jung ◽  
...  
Keyword(s):  
Partial Oxidation ◽  
Oxidation Reactions ◽  
Partial Oxidation Reactions ◽  
Catalytic Applications

Preparation of Cross-Linked Cellulase Aggregate and Application to Cool Finishing of Cotton Fabric

2021 ◽  
Vol 8 (3) ◽  
pp. 1-7
Author(s):  
Gang Bai ◽  
Bingbing Feng ◽  
Yanchun Liu ◽  
Shujiao Dai
Keyword(s):  
Water Vapor ◽  
Cotton Fabric ◽  
Silicone Oil ◽  
Air Permeability ◽  
Kinetic Friction ◽  
Capillary Effect ◽  
Bending Rigidity ◽  
Moisture Permeability ◽  
Treated Sample ◽  
The Stability

Cellulase was immobilized by cross-linked enzyme aggregation to improve the stability of cellulase. The prepared cross-linked cellulase aggregates (CLCAs) and ice silicone oil were used for the cool finishing of cotton fabric. The results showed that the CLCAs extended the cellulase stability compared to free cellulase. The surface softness, smoothness, moisture permeability, and air permeability of the cotton fabric increased after CLCAs and ice silicone oil treatment. Shearing rigidity of the treated sample was 0.44 cN/(cm·deg), bending rigidity was 0.0069 cN cm, and the drape coefficient was 29.3%. Coefficient of kinetic friction of the treated sample was 0.186. The capillary effect of the treated fabric was 12.1 cm/(30 min). Air permeability was 354.3 L/(m2·s). Moisture penetrability was 3.912 g/(m2·d). The thermal and water-vapor resistance were 0.0194 m2·°C/W and 4.691 Pa·m2/W, respectively.

Research on Variable Metric Chaos Optimization Modeling for the Prediction of Wastewater Treatment Plants Performance

2012 ◽  
Vol 428 ◽  
pp. 169-175
Author(s):  
Guo Kai Fu ◽  
Yi Yue Hu ◽  
Zhi Zhang
Keyword(s):  
Neural Network ◽  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Treatment System ◽  
Variable Metric ◽  
Chaos Optimization ◽  
Actual Operation ◽  
The Stability

A reliable model for any wastewater treatment plant is essential in order to provide a tool for predicting its performance and to form a basis for controlling the operation of the process. This would minimize the operation costs and assess the stability of environmental balance. For the multi-variable, uncertainty, non-linear characteristics of the wastewater treatment system, a variable metric chaos optimization neural network (VMCNW) prediction model is established standing on the actual operation data in the wasterwater treatment system. The model overcomes several disadvantages of the conventional BP neural network. Namely:slow convergence, low accuracy and difficulty in finding the global optimum.The results of model calculation show that the predicted value can better match measured value,played a effect of simulating and predicting and be able to optimize the operation status. The establishment of the predicting model provide a simple and practical way for the operation and management in wastewater treatment plant,and have good research and engineering practical value.

Catalytic partial oxidation reactions and reactors

1994 ◽  
Vol 49 (24) ◽  
pp. 3981-3994 ◽  
Author(s):  
L.D. Schmidt ◽  
M. Huff ◽  
S.S. Bharadwaj
Keyword(s):  
Partial Oxidation ◽  
Catalytic Partial Oxidation ◽  
Oxidation Reactions ◽  
Partial Oxidation Reactions
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