Studies of Three-Phase Hydrogenation of Nitrobenzene to Aniline in the Presence of a Ruthenium Catalyst

2018 ◽  
Vol 18 (4) ◽  
pp. 41-47 ◽  
Author(s):  
V. Yu. Doluda ◽  
A. E. Filatova ◽  
E. M. Sulman ◽  
V. G. Matveeva ◽  
S. P. Mikhailov ◽  
...  
Keyword(s):  
Process Parameters ◽  
Catalytic Hydrogenation ◽  
Hydrogen Pressure ◽  
Hypercrosslinked Polystyrene ◽  
Ruthenium Catalyst ◽  
Optimal Process ◽  
Catalytic Behavior ◽  
Partial Hydrogen Pressure ◽  
Three Phase ◽  
Technological Stage

Catalytic hydrogenation of nitrobenzene (NB) is an important technological stage in the production of aniline (AN). The catalytic behavior of hypercrosslinked polystyrene based ruthenium catalyst 3%Ru/MN270 in three-phase hydrogenation of NB to AN is discussed in the paper. The following parameters were varied during the studies: 0.12 to 0.24 mol/L NB, 1.11·10–4to 11.12·10–4mol/L catalyst, 160 to 190 °C, partial hydrogen pressure of 0.113 to 1.013 MPa. The optimal process parameters were determined to provide 98 % selectivity to aniline at 97 % conversion of nitrobenzene.

scholarly journals Mechanical properties optimization of the steering column based on multi-objective optimization design

2016 ◽  
Vol 8 (12) ◽  
pp. 168781401668294 ◽  
Author(s):  
Si Chen ◽  
Zhaohui Wang ◽  
Mi Lv
Keyword(s):  
Mechanical Properties ◽  
Process Parameters ◽  
Optimization Design ◽  
Strain Difference ◽  
Optimization Method ◽  
Equivalent Strain ◽  
Multi Objective Optimization ◽  
Optimal Process ◽  
Multi Objective ◽  
Initial Results

The mechanical properties of the steering column have a significant influence on the comfort and stability of a vehicle. In order for the mechanical properties to be improved, the rotary swaging process of the steering column is studied in this article. The process parameters, including axial feed rate, hammerhead speed, and hammerhead radial reduction, are systematically analyzed and optimized based on a multi-objective optimization design. The response surface methodology and the genetic algorithm are employed for optimal process parameters to be obtained. The maximum damage value, the maximum forming load, and the equivalent strain difference obtained with the optimal process parameters are, respectively, decreased by 30.09%, 7.44%, and 57.29% compared to the initial results. The comparative results present that the quality of the steering column is improved. The torque experiments and fatigue experiments are conducted with the optimal steering column. The maximum torque is measured to be 260 NM, and the service life is measured to be 2 weeks (40 NM, 2500 times), which are, respectively, increased by 8.3% and 8.69% compared to the initial results. The above results display that the mechanical properties of the steering column are optimized to verify the feasibility of the multi-objective optimization method.

Schadenserfassung auf Radsatzlaufflächen/Defect detection on wheelset treads – Measurement of Magnetic Barkhausen Noise to detect varying workpiece conditions

2019 ◽  
Vol 109 (11-12) ◽  
pp. 811-815
Author(s):  
B. Denkena ◽  
B. Bergmann ◽  
H. Blech
Keyword(s):  
Acoustic Emission ◽  
Process Parameters ◽  
Defect Detection ◽  
Material Properties ◽  
Barkhausen Noise ◽  
Magnetic Barkhausen Noise ◽  
Optimal Process ◽  
Process Reliability

Unterschiedliche Belastungshistorien von Eisenbahnrädern führen zu Werkstoffveränderungen in der Lauffläche. Diese verursachen sporadisches Werkzeugversagen und verringern so die Prozesssicherheit. Die Messung der Material- und Prozesseigenschaften mit Barkhausenrauschen und Körperschall erlauben, individuelle Bearbeitungsparameter für jedes Exemplar festzulegen. Gezeigt werden die Herausforderungen in der Radsatzbearbeitung, und welche Informationen sich durch die Messtechniken gewinnen lassen.   Different load histories of train wheels lead to high variance of material properties on the running tread. Those cause unpredictable tool break and reduce process reliability. The measurement of magnetic Barkhausen noise and acoustic emission allow to gain information of the workpiece and the running process, to find optimal process parameters for the reconditioning of every individual wheel. Typical issues in train wheel machining and results of measurements are presented.

Selection of selective laser sintering materials for different applications

2015 ◽  
Vol 21 (6) ◽  
pp. 630-648 ◽  
Author(s):  
Sunil Kumar Tiwari ◽  
Sarang Pande ◽  
Sanat Agrawal ◽  
Santosh M. Bobade
Keyword(s):  
Process Parameters ◽  
High Performance ◽  
Material Selection ◽  
Selective Laser Sintering ◽  
Laser Sintering ◽  
Optimal Process ◽  
Content Type ◽  
Volume Production ◽  
High Performance Application ◽  
Selection Of

Purpose – The purpose of this paper is to propose and evaluate the selection of materials for the selective laser sintering (SLS) process, which is used for low-volume production in the engineering (e.g. light weight machines, architectural modelling, high performance application, manufacturing of fuel cell, etc.), medical and many others (e.g. art and hobbies, etc.) with a keen focus on meeting customer requirements. Design/methodology/approach – The work starts with understanding the optimal process parameters, an appropriate consolidation mechanism to control microstructure, and selection of appropriate materials satisfying the property requirement for specific application area that leads to optimization of materials. Findings – Fabricating the parts using optimal process parameters, appropriate consolidation mechanism and selecting the appropriate material considering the property requirement of applications can improve part characteristics, increase acceptability, sustainability, life cycle and reliability of the SLS-fabricated parts. Originality/value – The newly proposed material selection system based on properties requirement of applications has been proven, especially in cases where non-experts or student need to select SLS process materials according to the property requirement of applications. The selection of materials based on property requirement of application may be used by practitioners from not only the engineering field, medical field and many others like art and hobbies but also academics who wish to select materials of SLS process for different applications.

scholarly journals Fractionation of Birch Wood by Integrating Alkaline-Acid Treatments and Hydrogenation in Ethanol over a Bifunctional Ruthenium Catalyst

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1362
Author(s):  
Boris N. Kuznetsov ◽  
Sergey V. Baryshnikov ◽  
Angelina V. Miroshnikova ◽  
Aleksandr S. Kazachenko ◽  
Yuriy N. Malyar ◽  
...  
Keyword(s):  
Microcrystalline Cellulose ◽  
Catalytic Hydrogenation ◽  
Liquid Product ◽  
Gel Permeation Chromatography ◽  
Ruthenium Catalyst ◽  
Birch Wood ◽  
Gaseous Products ◽  
Liquid Products ◽  
First Time

For the first time, the fractionation of birch wood into microcrystalline cellulose, xylose and methoxyphenols is suggested based on the integration of alkali-acid pretreatments and hydrogenation in ethanol over a bifunctional Ru/C catalyst. It is established that removal of hemicelluloses during pretreatments of birch wood influences the yields of the liquid, gaseous and solid products of the non-catalytic and catalytic hydrogenation of pretreated samples in ethanol at 225 °C. The bifunctional Ru/carbon catalyst affects in different ways the conversion and yields of products of hydrogenation of the initial and acid- and alkali-pretreated birch wood. The most noticeable influence is characteristic of the hydrogenation of the acid-pretreated wood, where in contrast to the non-catalytic hydrogenation, the wood conversion and the yields of liquid products increase but the yields of the solid and gaseous products decrease. GC-MS, gel permeation chromatography and elemental analysis were used for characterization of the liquid product composition. The molecular mass distribution of the liquid products of hydrogenation of the initial and pretreated wood shifts towards the low-molecular range in the presence of the catalyst. From the GC-MS data, the contents of monomer compounds, predominantly 4-propylsyringol and 4-propanolsyringol, increase in the presence of the ruthenium catalyst. The solid products of catalytic hydrogenation of the pretreated wood contain up to 95 wt% of cellulose with the structure, similar to that of microcrystalline cellulose.

scholarly journals Optimization of SLS forming parameters in the dimensional accuracy of formed parts

2021 ◽  
Vol 233 ◽  
pp. 01069
Author(s):  
Hong ZHU ◽  
Gaoyan HOU
Keyword(s):  
Process Parameters ◽  
Selective Laser Sintering ◽  
Dimensional Accuracy ◽  
Scanning Speed ◽  
Axis Deviation ◽  
Reference Standard ◽  
Optimal Process ◽  
Molded Part ◽  
Formed Part ◽  
Powder Forming

In selective laser sintering powder forming, the performance and dimensional accuracy of the formed part are affected by the process parameters. Different materials have different process parameters, and there is still no reference standard for PA materials. To solve this problem, in response to this problem, PA2200 material was selected, and the influence of scanning interval and scanning speed on the dimensional accuracy of the formed part was analyzed. Through theoretical analysis and experiments, the optimal process parameters were obtained. The best combination of parameters is a scanning speed of 4000mm/s, a scanning interval of 0.5mm, and the size of the molded part has a X-axis deviation -0.35%, a Y-axis deviation -0.4%, and a Z-axis deviation -0.25%.

scholarly journals Research on the Molding Design and Optimization of the Molding Process Parameters of the Automobile Trunk Trim Panel

2020 ◽  
Vol 2020 ◽  
pp. 1-19
Author(s):  
Youmin Wang ◽  
Zhaozhe Zhu ◽  
Lingfeng Tang ◽  
Qinshuai Jiang
Keyword(s):  
Process Parameters ◽  
Heating Temperature ◽  
Process Parameter ◽  
Shrinkage Rate ◽  
Optimal Process ◽  
Molding Process ◽  
Rate Maximum ◽  
Thinning Rate ◽  
Trim Panel

In order to put forward the theoretical calculation formula for the compression force of the compression mold of the trunk trim panel, obtain the influence trend of the process parameters on the molding quality of the trunk trim panel, and obtain the optimal process parameters combination for the compression molding of the trunk trim panel, four process parameters, the heating temperature, time, compression pressure, and holding time, which affected the compression molding, were selected as the level factors; the maximum thinning rate, maximum thickening rate, and shrinkage rate of the trunk trim panel were selected as evaluation indicators and orthogonal experiments were designed and completed; the comprehensive weighted scoring method was used to obtain the comprehensive score results and obtain the comprehensive evaluation indicators of the best combination of process parameters of trunk trim panel; BP neural network and genetic algorithm were used to study the change trend of the evaluation indicators of trunk trim panel with the changes of process parameters; based on the optimal process parameter combination and the established neural network’s prediction function, the maximum thinning rate, maximum thickening rate, and shrinkage rate under a single process parameter change could be predicted, and the influence of a single process parameter on the maximum thinning rate, maximum thickening rate, and shrinkage rate could be obtained; the process parameters were optimized, and a maximum thinning rate of 28%, a maximum thickening rate of 4.3%, and a shrinkage rate of 0.8% were obtained; the optimal molding process parameters of the trunk trim panel were heating temperature of 209°C, heating time of 62 s, molding pressure of 14 kPa, and holding pressure time of 49 s; after optimization, the maximum shrinkage rate was 28.0880%, the maximum thickening rate was 44.3264%, and the shrinkage rate was 0.8901%; according to the optimal process parameters, the quality of the trunk trim panel was very good, which met the production quality requirements.

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