scholarly journals Evaluation of the Textural Parameters of Zeolite Beta in LDPE Catalytic Degradation: Thermogravimetric Analysis Coupled with FTIR Operando Studies

Molecules ◽  
2020 ◽  
Vol 25 (4) ◽  
pp. 926 ◽  
Author(s):  
Kamila Pyra ◽  
Karolina A. Tarach ◽  
Ewa Janiszewska ◽  
Dorota Majda ◽  
Kinga Góra-Marek
Keyword(s):  
Thermogravimetric Analysis ◽  
Catalytic Efficiency ◽  
High Strength ◽  
Hydrocarbon Chain ◽  
Decomposition Temperature ◽  
Operating Conditions ◽  
Oil Refining ◽  
Reaction Products ◽  
Chemical Production ◽  
The Individual

Zeolite-based catalysts are globally employed in many industrial processes, such as crude-oil refining and bulk chemical production. In this work, the cracking of low-density polyethylene (LDPE) was thoroughly followed in a FTIR operando study to examine the catalytic efficiency of purely microporous zeolites of various textural characteristics. To provide complementary and valuable information on the catalytic activity of the zeolite studied, the thermogravimetric analysis results were compared with yields of the products generated under operating conditions. The reaction products were analyzed via GC–MS to determine the hydrocarbon chain distribution in terms of paraffin, olefins, and aromatics. The individual impact of textural and acidic parameters on catalytic parameters was assessed. The accumulation of bridging hydroxyls of high strength in the zeolite benefited the decrease in polymer decomposition temperature. Through a strategic comparison of purely microporous zeolites, we showed that the catalytic cracking of LDPE is dominated by the acidic feature inherent to the microporous environment.

Testing and Analysis of Steel Strip Reinforcement for Pipeline External Rehabilitation

2010 ◽  
Author(s):  
David J. Miles ◽  
Tim J. M. Bond ◽  
Raymond N. Burke ◽  
Ruben van Schalkwijk
Keyword(s):  
Steel Strip ◽  
New Technology ◽  
High Strength ◽  
Full Scale ◽  
Operating Conditions ◽  
Operating Pressure ◽  
Batch Tests ◽  
Girth Welds ◽  
The Individual ◽  
Pipeline Design

A new technology for external rehabilitation of pipelines, known as XHab™, has been developed. This method involves wrapping multiple layers of ultra-high strength steel strip (UHSS) in a helical form continuously over an extended length of pipeline using a dedicated forming and wrapping machine. The reinforcement afforded by the strip can be used to bring a defective section of pipe (e.g. externally corroded or dented) back to its original allowable operating conditions, or even to increase the allowable operating pressure if the desired operating conditions exceed the original pipeline design limits. This paper describes the full scale burst testing and analysis of defective pipes which have been repaired using the XHab process. The full scale test sections are 30″ × 0.5″ API 5L X52 DSAW pipe and include the following specimens: • Bare pipe with no defects; • Bare pipe with single machined defect; • Wrapped pipe with single machined defect and designed reinforcement; • Wrapped pipe with single machined defect and insufficient reinforcement; • Wrapped pipe with interacting defect array and designed reinforcement. The above full scale burst tests are supplemented by FEA models using ABAQUS. The material models for the steel pipe, UHSS strip, defect patch material and strip adhesive are based on measured data from the batch tests and tuned against the control burst test results. The structural behavior in the individual metallic and non-metallic elements can therefore be examined more closely, particularly in the region of the defect and where the wrapped strip crosses seam and girth welds.

Теория гетерогенного катализа. Теория хемосорбции

2021 ◽  
Author(s):  
Василий Садовников
Keyword(s):  
Heterogeneous Catalysis ◽  
Potential Energy ◽  
Publishing House ◽  
Cell Number ◽  
Oil Refining ◽  
Lateral Interaction ◽  
Reaction Products ◽  
Crystal Face ◽  
Independent Particle ◽  
The Face

This monograph is a continuation of the monograph by V.V. Sadovnikov. Lateral interaction. Moscow 2006. Publishing house "Anta-Eco", 2006. ISBN 5-9730-0017-6. In this work, the foundations of the theory of heterogeneous catalysis and the theory of chemisorption are more easily formulated. The book consists of two parts, closely related to each other. These are the theoretical foundations of heterogeneous catalysis and chemisorption. In the theory of heterogeneous catalysis, an experiment is described in detail, which must be carried out in order to isolate the stages of a catalytic reaction, to find the stoichiometry of each of the stages. This experiment is based on the need to obtain the exact value of the specific surface area of the catalyst, the number of centers at which the reaction proceeds, and the output curves of each of the reaction products. The procedures for obtaining this data are described in detail. Equations are proposed and solved that allow calculating the kinetic parameters of the nonequilibrium stage and the thermodynamic parameters of the equilibrium stage. The description of the quantitative theory of chemisorption is based on the description of the motion of an atom along a crystal face. The axioms on which this mathematics should be based are formulated, the mathematical apparatus of the theory is written and the most detailed instructions on how to use it are presented. The first axiom: an atom, moving along the surface, is present only in places with minima of potential energy. The second axiom: the face of an atom is divided into cells, and the position of the atom on the surface of the face is set by one parameter: the cell number. The third axiom: the atom interacts with the surrounding material bodies only at the points of minimum potential energy. The fourth axiom: the solution of the equations is a map of the arrangement of atoms on the surface. The fifth axiom: quantitative equations are based on the concept of a statistically independent particle. The formation energies of these particles and their concentration are calculated by the developed program. The program based on these axioms allows you to simulate and calculate the interaction energies of atoms on any crystal face. The monograph is intended for students, post-graduate students and researchers studying work and working in petrochemistry and oil refining.

EASTERN STAINLESS TYPE 310S

Alloy Digest ◽  
1984 ◽  
Vol 33 (8) ◽  
Keyword(s):  
High Temperatures ◽  
Elevated Temperatures ◽  
High Strength ◽  
Heat Treating ◽  
Oil Refining ◽  
Steel Company ◽  
Plant Equipment ◽  
The Many ◽  
Corrosion And Oxidation ◽  
Refining Equipment

Abstract EASTERN STAINLESS TYPE 310S has high resistance to corrosion and oxidation at high temperatures. It also has high strength at elevated temperatures. Thus it is especially suitable for service at high temperatures. It is very ductile and can be welded readily. Among the many applications for Type 310S, a few typical uses include annealing boxes, chemical plant equipment, fire box sheets, furnace linings, heat exchangers, oil-refining equipment, kiln linings and tube hangers. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-450. Producer or source: Eastern Stainless Steel Company.

scholarly journals Crystal growth of clathrate hydrate formed with H2 + CO2 mixed gas and tetrahydropyran

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Meku Maruyama ◽  
Riku Matsuura ◽  
Ryo Ohmura
Keyword(s):  
Crystal Growth ◽  
Synthesis Gas ◽  
Water System ◽  
Hydrate Formation ◽  
Growth Dynamics ◽  
Operating Conditions ◽  
Mixed Gas ◽  
Thermodynamic Conditions ◽  
The Individual ◽  
And Storage

AbstractHydrate-based gas separation technology is applicable to the CO2 capture and storage from synthesis gas mixture generated through gasification of fuel sources including biomass. This paper reports visual observations of crystal growth dynamics and crystal morphology of hydrate formed in the H2 + CO2 + tetrahydropyran (THP) + water system with a target for developing the hydrate-based CO2 separation process design. Experiments were conducted at a temperature range of 279.5–284.9 K under the pressure of 4.9–5.3 MPa. To simulate the synthesis gas, gas composition in the gas phase was maintained around H2:CO2 = 0.6:0.4 in mole fraction. Hydrate crystals were formed and extended along the THP/water interface. After the complete coverage of the interface to shape a polycrystalline shell, hydrate crystals continued to grow further into the bulk of liquid water. The individual crystals were identified as hexagonal, tetragonal and other polygonal-shaped formations. The crystal growth rate and the crystal size varied depending on thermodynamic conditions. Implications from the obtained results for the arrangement of operating conditions at the hydrate formation-, transportation-, and dissociation processes are discussed.

scholarly journals Micromagnetic Characterization of Operation-Induced Damage in Charpy Specimens of RPV Steels

2021 ◽  
Vol 11 (7) ◽  
pp. 2917
Author(s):  
Madalina Rabung ◽  
Melanie Kopp ◽  
Antal Gasparics ◽  
Gábor Vértesy ◽  
Ildikó Szenthe ◽  
...  
Keyword(s):  
Neutron Irradiation ◽  
Pressure Vessel ◽  
Operating Conditions ◽  
Magnetic Characteristics ◽  
Pressure Vessel Steel ◽  
Training Procedure ◽  
Vessel Steel ◽  
Before And After ◽  
The Individual ◽  
Magnetic Adaptive Testing

The embrittlement of two types of nuclear pressure vessel steel, 15Kh2NMFA and A508 Cl.2, was studied using two different methods of magnetic nondestructive testing: micromagnetic multiparameter microstructure and stress analysis (3MA-X8) and magnetic adaptive testing (MAT). The microstructure and mechanical properties of reactor pressure vessel (RPV) materials are modified due to neutron irradiation; this material degradation can be characterized using magnetic methods. For the first time, the progressive change in material properties due to neutron irradiation was investigated on the same specimens, before and after neutron irradiation. A correlation was found between magnetic characteristics and neutron-irradiation-induced damage, regardless of the type of material or the applied measurement technique. The results of the individual micromagnetic measurements proved their suitability for characterizing the degradation of RPV steel caused by simulated operating conditions. A calibration/training procedure was applied on the merged outcome of both testing methods, producing excellent results in predicting transition temperature, yield strength, and mechanical hardness for both materials.

scholarly journals Electrochemical treatment of high strength chrome bathwater: A comparative study for best-operating conditions

2021 ◽  
pp. 100093
Author(s):  
Vishakha Gilhotra ◽  
Rekha Yadav ◽  
Aditi Sugha ◽  
Laxmi Das ◽  
Ashutosh Vashisht ◽  
...  
Keyword(s):  
Comparative Study ◽  
High Strength ◽  
Electrochemical Treatment ◽  
Operating Conditions

Sacrificial Protection Efficiency Calculations Based on the Results of Stochastically Simulating the Parameters

2021 ◽  
Vol 410 ◽  
pp. 566-571
Author(s):  
Svetlana S. Vinogradova ◽  
Ramilya F. Tazieva ◽  
Anna N. Akhmetova
Keyword(s):  
Operating Conditions ◽  
Oil Refining ◽  
Environmental Aspects ◽  
Protection Level ◽  
Protection Efficiency ◽  
Internal Surfaces ◽  
Protection Systems ◽  
Active Protection ◽  
Refining Processes ◽  
Sacrificial Protection

Unique corrosion conditions in oil refining processes lead to the necessity of using passive and active protection systems, aimed at preventing from damages and ensuring the correct operating conditions of machines. To prevent from the development of corrosion processes on the internal surfaces of horizontal settlers, sacrificial protection is used. Before installing such a protection, they usually calculate the number of protectors to be installed in parallel. Some inputs are stochastic by their nature, which should be considered in assessing the risk of non-achieving the required protection level. The probabilistic model proposed to calculate the parameters of sacrificial tank protection that allows performing an exploratory design based on considering various environmental aspects to decide on the efficiency of sacrificial protection and to assess the achievement of the required protection level.

Powder Spheroidization Using Induction Plasma Technology

2000 ◽  
Author(s):  
N.M. Dignard ◽  
M.I. Boulos
Keyword(s):  
Energy Efficiency ◽  
Maximum Energy ◽  
Operating Conditions ◽  
Side Reactions ◽  
Induction Plasma ◽  
Silica Alumina ◽  
Change In The Mean ◽  
The Individual ◽  
Semi Empirical ◽  
Objective Being

Abstract An experimental study of the spheroidization efficiency of induction plasma processes was completed. The main objective being to obtain models which could be subsequently used for the prediction of the spheroidization efficiency for various powders and plasma operating conditions. Silica, alumina, chromium oxide and zirconia powders were treated during the experimentation. For the plasma treatment of the powders the installation used had a maximum available power of 50 kW with an operating frequency of 3 MHz. Operating conditions were varied such to minimize side reactions and the evaporation of powders. The resulting powders did show the presence of cavities and a slight change in the mean diameters. The maximum energy efficiency based semi-empirical model did predict the spheroidization efficiency of the particles beyond a defined critical point known as the maximum energy efficiency point. For the model, the maximum energy efficiency is distinct for the individual powders but remain within a defined range which is reflected in the small variations in the Z constant.

Research into Thermocatalytic Propane-to-Propylene Synthesis Using Iron-Containing Composite Carbon Materials

2021 ◽  
pp. 100-114
Author(s):  
E.B. Markova ◽  
A.G. Cherednichenko ◽  
L.S. Akhmedova ◽  
Yu.M. Averina ◽  
Yu.M. Serov
Keyword(s):  
Carbon Nanotubes ◽  
Iron Oxide ◽  
Service Life ◽  
Oil And Gas ◽  
Carbon Matrix ◽  
Propane Conversion ◽  
Reaction Products ◽  
Chemical Production ◽  
Catalytic Systems ◽  
Propylene Selectivity

The development of modern thermocatalytic technologies for processing oil and gas raw materials is one of the promising areas for the advancement of chemical production. New highly efficient catalytic systems with the required technical characteristics and long service life play an essential role in solving these issues. The paper focuses on obtaining propylene by selective propane dehydrogenation. In the course of the experiments, composite iron-containing catalysts were synthesized, in which the active component is iron oxide in combination with an inert carbon matrix. FAS activated carbon and carbon nanotubes were used as the matrix. As a result of the synthesis on the catalyst surface it was possible to obtain catalytic centers that transfer electrons by changing the degree of iron oxidation when converting the starting materials into the target reaction products. Findings of research show that the obtained iron-containing catalysts significantly increase the efficiency of the process in comparison with the efficiency of thermal cracking of propane. Thus, the Fe3+/FAS catalyst showed a conversion rate of the initial reagent of 68 % and a propylene selectivity of about 42 %. Further transition to catalytic systems based on singlelayer and double-layer carbon nanotubes modified with iron oxide (Fe3+/CNTI and Fe3+/CNTII) made it possible to obtain propane conversion up to 37--40 % with a decrease in propylene selectivity to 29--30 %. Studies of the service life of the synthesized catalytic systems and the possibility of their regeneration show that, with account for the regeneration, the activity of the catalysts and the main technical characteristics of the propane-to-propylene cracking process remain unchanged for 10 working cycles

scholarly journals Forecasting the properties of linear block-copoliurethanes based on oligoesters of regular structure

2021 ◽  
pp. 4-10
Author(s):  
V.N. Anisimov ◽  
◽  
V.V. Anisimov
Keyword(s):  
Molecular Structure ◽  
Regular Structure ◽  
High Strength ◽  
Operating Conditions ◽  
Properties Of Materials ◽  
Reasonable Choice ◽  
The Relationship ◽  
Tribotechnical Characteristics ◽  
Quality Indexes ◽  
Linear Block

We showed that the development of recommendations for a reasonable choice of linear block copolyurethanes that would be optimal for given operating conditions is still intuitive and does not consider the features of the molecular structure and the nature of initial components. We suggested a new scientifically grounded approach to the creation of linear block-copolyurethanes with increased wear resistance in relation to strength, deformation, thermophysical and tribotechnical characteristics. To simplify analysis of the properties of the studied materials, a mathematical model was developed, which describes the relationship between all considered properties of materials and their structure. We proposed to assess the relationship between structure and properties of the investigated materials by using quality indexes. Maximum values of quality indexes, depending on the operating conditions, correspond to different contents of hard blocks (Pc), and, consequently, to different molecular structure of the studied polyurethanes. Thus, it is reasonable to use block-copolyurethanes based on OBGA500 with a maximum content of hard blocks (Рс>60%) for operating conditions where it is necessary to provide high strength characteristics. Polyurethanes synthesized with the formation of clusters of hard blocks in the range of 45–55% are recommended for the use as wear-resistant materials.

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