Hydrogenation of polyaromatic compounds over NiCo/chrysotile catalyst

The activity and selectivity of the bimetallic NiCo/chrysotile catalyst during the hydrogenation of model objects (anthracene and phenanthrene) for 1 hour at an initial hydrogen pressure of 3 MPa and a temperature of 400 °C were studied. The chrysotile mineral used as a substrate for active centers of nickel and cobalt is a waste product of asbestos production at Kostanay Minerals JSC (the Republic of Kazakhstan). The catalyst was characterized by a complex of methods of physical and chemical analysis. The chrysotile mineral consists of nanotubes with an inner diameter of about 10 nm and an outer diameter of about 60 nm. The amount of hydrogenation products is 61.91 %, destruction — 15.08 % and isomerization — 8.37 % during the hydrogenation of anthracene. The amount of hydrogenation products is 26.09 %, and that of destruction is 2.51 % during the hydrogenation of phenanthrene. It was found that the catalyst selectively accelerates the hydrogenation reaction and allows increasing the yields of hydrogenation products. The schemes of the hydrogenation reaction of model objects were drawn up according to the results of gas chromatography-mass spectrometric analysis of hydrogenates.

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Hydrogenation of Polyaromatic Compounds Over NiCo/chrysotile Catalyst

10.21203/rs.3.rs-389410/v1 ◽

2021 ◽

Author(s):

Murzabek Baikenov ◽

Darzhan Aitbekova ◽

Sergey Kim ◽

Feng Yung Ma ◽

Nazerke Balpanova ◽

...

Keyword(s):

Gas Chromatography ◽

Hydrogen Pressure ◽

Hydrogenation Reaction ◽

Mass Spectrometric ◽

Spectrometric Analysis ◽

Outer Diameter ◽

Cobalt Ions ◽

Inner Diameter ◽

Initial Hydrogen Pressure ◽

Physical And Chemical

Abstract The activity and selectivity of the NiCo/chrysotile catalyst during the hydrogenation of model objects (anthracene and phenanthrene) for 1 hour at an initial hydrogen pressure of 3 MPa and a temperature of 400 °C were studied. The catalyst is characterized by a complex of methods of physical and chemical analysis. The chrysotile mineral used as a substrate consists of nanotubes with an inner diameter of about 10 nm and an outer diameter of about 60 nm. When a catalyst is prepared by wet mixing, chrysotile nanotubes can be filled with nickel and cobalt ions from solutions of the corresponding salts. The selectivity of the catalyst in hydrogenation was shown. The yields of the products of hydrogenation and degradation of anthracene are 62% and 15%, respectively. The yields of products of hydrogenation and destruction of phenanthrene are 26% and 2.5%, respectively. According to the results of gas chromatography-mass spectrometric analysis of hydrogenates, the schemes of the hydrogenation reaction of model objects were drawn up.

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IDENTIFIKASI PRODUK TURUNAN HYDROPROCESSING MODEL MINYAK SINTETIS BATUBARA MENGGUNAKAN GC-FID/NPD/MS

Jurnal Energi dan Lingkungan (Enerlink) ◽

10.29122/elk.v6i1.1563 ◽

2010 ◽

Vol 6 (1) ◽

Author(s):

Muhammad Hanif ◽

Yusnitati Yusnitati ◽

Nasikin Nataadmadja

Keyword(s):

Gas Chromatography ◽

Reaction Temperature ◽

Hydrogen Pressure ◽

Selective Adsorption ◽

Hydrogenation Reaction ◽

Flame Ionization ◽

Aromatic Hydrogenation ◽

Initial Hydrogen Pressure ◽

Butyl Benzene

An analysis of identifying a derivative product of liquefied coal modelhydroprocessing was conducted. For that purpose, an integration gaschromatography flame ionization-nitrogen phosphorous detector and massspectrometry (GC-FID/NPD/MS) was used. Hydroprocessing process wasperformed by vibrating micro autoclave tipe batch using Ni-W/Alumina catalystunder initial hydrogen pressure 6 MPa, reaction temperature 375oC and one hourretention time. The analysis result showed that the predominant reaction werehydrogenation, hydrodenitrogenation (HDN) and hydrodeoxygenation (HDO).The HDO of methyl phenol and ethyl phenol took place faster than the otherhydroprocessing reactions such as HDN of quinoline and aromatic hydrogenation(butyl benzene, naphthalene, phenanthrene dan pyrene). This indicates that thehydrogenation reaction or the cleavage of C-O bonding took place very fast thatalkyl could not be detected in the oil. The HDN reaction or the cleavage of C-Ntook place slower but the the nitrogen containing compound vanished faster dueto selective adsorption of the catalyst. However the hydrogenation reaction ofmono-aromatic took place faster than poly-aromaticKata kunci: gas chromatography, identifikasi senyawa, model minyak sintetis

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Physical and Chemical Characteristics of Cobalt Catalysts in the Process of Hydrogenating Acetylene

Eurasian Chemico-Technological Journal ◽

10.18321/ectj891 ◽

2019 ◽

Vol 21 (4) ◽

pp. 341

Author(s):

S.K. Tanirbergenova ◽

D.A. Tugelbaeva ◽

G.M. Moldazhanova ◽

S.R. Khairullin

Keyword(s):

Specific Surface ◽

Xrd Analysis ◽

Physicochemical Characteristics ◽

Hydrogenation Reaction ◽

Cobalt Catalysts ◽

X Ray Diffraction ◽

Active Components ◽

Active Centers ◽

X Ray ◽

Physical And Chemical

This paper describes the results of studies of the physicochemical characteristics of cobalt catalysts and methods for modifying them with alumina. The elemental composition, the peculiarities of formation of the structural and phase composition of cobalt catalysts are studied. The influence of the carbonization process of cobalt catalysts at a temperature of 550 °С on the specific surface is determined. The increase in the specific surface in cobalt catalysts was studied to proceed uniformly, as the formation of large grains and accumulations of active components was not observed. According to the results of X-ray diffraction (XRD) analysis, the formation of aluminosilicate phases, cobalt oxide, and cobalt are detected. The surface of cobalt samples was investigated by scanning electron microscope (SEM). Electron microscopy revealed crystallites of cobalt particles with sizes of 300‒400 nm. It is shown that in the course of modification with alumina, in cobalt catalysts active centers are formed that enhance their catalytic properties during the reaction of hydrogenation of acetylene to ethylene. It is found that cobalt catalysts exhibit catalytic activity in the acetylene hydrogenation reaction. On cobalt catalysts at a temperature of 160 °C at a conversion of 82%, the yield of ethy lene is 64.1%.

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Morphological Changes in Lamellar Macular Holes According to SD-OCT Examination over a Long Observation Period

Diagnostics ◽

10.3390/diagnostics11071145 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1145

Author(s):

Magdalena Kal ◽

Izabela Chojnowska-Ćwiąkała ◽

Mateusz Winiarczyk ◽

Monika Jasielska ◽

Jerzy Mackiewicz

Keyword(s):

Retinal Thickness ◽

Morphological Changes ◽

Outer Diameter ◽

Corrected Visual Acuity ◽

Macular Holes ◽

Kolmogorov Smirnov ◽

Inner Diameter ◽

Observation Period ◽

Sd Oct

Background: The aim of this study was to evaluate the quantitative morphological changes in lamellar macular holes (LMHs) based on SD-OCT examinations and to assess the correlations among minimal retinal thickness (MRT), reading vision (RV), and best corrected visual acuity (BCVA) over a 36-month follow-up period. Methods: A group of 40 patients (44 eyes) with LMH was evaluated, with an average age of 69.87 (SD = 10.14). The quantitative parameters monitored in the follow-up period (at 0, 3, 6, 12, 18, 24, 30, and 36 months) were tested for normality of distribution by Shapiro–Wilk and Kolmogorov–Smirnov tests. Results: The RV and BCVA values were stable, and no significant changes were found at any of the check-ups during the 36-month follow-up period (BCVA p = 0.435 and RV p = 0.0999). The analysis of individual quantitative LMH parameters during the 36-month follow-up period did not demonstrate statistically significant differences: MRT (p = 0.461), Max RT temporal (p = 0.051), Max RT nasal (p = 0.364), inner diameter (ID) (p = 0.089), and outer diameter (OD) (p = 0.985). Conclusions: The observations at 0, 6, 12, 18, 24, 30, and 36 months revealed moderate and significant correlations between RV and MRT. No significant correlation between BCVA and MRT was observed.

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Influence of fully submerged permanent magnets in the evaluation of heat transfer and performance analysis of single slope glass solar still

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/09576509211031021 ◽

2021 ◽

pp. 095765092110310

Author(s):

Ajay Kumar Kaviti ◽

Akkala Siva Ram ◽

Amit Kumar Thakur

Keyword(s):

Heat Transfer ◽

Permanent Magnets ◽

Outer Diameter ◽

Solar Still ◽

Transfer Coefficients ◽

Heat Transfer Coefficients ◽

Inner Diameter ◽

Evaporative Heat Transfer ◽

And Performance ◽

Depth Water

In this experimental study, permanent magnets with three different sizes (M-1: 32 mm inner diameter, 70 mm outer diameter and 15 mm thick, M-2: 25 mm inner diameter, 60 mm outer diameter and 10 mm thick, M-3: 22 mm inner diameter, 45 mm outer diameter and 9 mm thick) are fully submerged in the single-slope glass solar still. The performance of magnetic solar stills (MSS) with three different sizes at 2 cm depth water to ensure that magnets are fully submerged is compared with conventional solar still (CSS) at the location 17.3850°N, 78.4867°E. Tiwari model is adapted to calculate the heat transfer coefficients (HTC), internal and exergy efficiencies. MSS with M-1, M-2 and M-3 significantly enhanced the convective, radiative, and evaporative heat transfer rate for the 2 cm depth of water. This is due to the desired magnetic treatment of water, which reduces the surface tension and increases the hydrogen bonds. The MSS's total internal HTC, instantaneous efficiencies led CSS by 25.52%, 28.8%, respectively, with M-1. Having various magnetic fields due to different magnets sizes increases MSS's exergetic efficiency by 33.61% with M-1, 33.76% with M-2, and 42.25% with M-3. Cumulative yield output for MSS with M-1, M-2, and M-3 is 21.66%, 17.64%, 15.78% higher than CSS. The use of permanent magnets of different sizes in the MSS is a viable, economical and straight forward technique to enhance productivity.

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Self-Organized, Tubular Hybrid Vascular Tissue Composed of Vascular Cells and Collagen for Low-Pressure-Loaded Venous System

Cell Transplantation ◽

10.1177/096368979500400609 ◽

1995 ◽

Vol 4 (6) ◽

pp. 597-608 ◽

Cited By ~ 30

Author(s):

Jiro Hirai ◽

Takehisa Matsuda

Keyword(s):

Vascular Tissue ◽

Venous System ◽

Seeding Density ◽

Outer Diameter ◽

Type I ◽

Dependent Manner ◽

Mixed Solution ◽

Vascular Cells ◽

Collagen Concentration ◽

Inner Diameter

A tubular, hierarchically structured hybrid vascular tissue composed of vascular cells and collagen was prepared. First, a cold mixed solution of bovine aortic smooth muscle cells (SMCs) and Type I collagen was poured into a tubular glass mold composed of a mandrel and a sheath (example of dimensions: inner diameter, 1.5 mm; outer diameter, 7 mm; length, 7 cm). Upon incubation at 37°C, an SMC-incorporated collagenous gel was formed. After the sheath was removed, the resulting fragile tissue, when cultured in medium, thinned in a time-dependent manner to form an opaque, dense tissue. Higher SMC seeding density and lower initial collagen concentration induced more rapid and prominent shrinkage of the tissue. Morphologic investigation showed that over time, bipolarly elongated SMCs and collagen fiber bundles became positioned around the mandrel. Both components became circumferentially oriented. When the mandrel was removed, a tubular hybrid medial tissue was formed. A hybrid vascular tissue with a hierarchical structure was constructed by seeding endothelial cells onto the inner surface of the hybrid medial tissue. Prepared tissues tolerated luminal pressures as great as 100 mmHg and mechanical stress applied during an anastomotic procedure. This method allowed us to prepare a tubular hybrid medial tissue of predetermined size (inner diameter, wail thickness, and length) by selecting appropriate mold design, initial collagen concentration, and SMC seeding density. Such hybrid vascular tissues may provide physiological functions when implanted into the venous system.

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Hydrogenation of methylacetylene. III. The reaction of methylacetylene with hydrogen catalyzed by nickel, copper, and their alloys

Canadian Journal of Chemistry ◽

10.1139/v68-101 ◽

1968 ◽

Vol 46 (4) ◽

pp. 623-633 ◽

Cited By ~ 12

Author(s):

R. S. Mann ◽

K. C. Khulbe

Keyword(s):

Activation Energy ◽

Nickel Catalyst ◽

Hydrogen Pressure ◽

Constant Volume ◽

Temperature Dependent ◽

Nickel Copper ◽

Wide Range ◽

Initial Hydrogen Pressure

The reaction between methylacetylene and hydrogen over unsupported nickel, copper, and their alloys has been investigated in a static constant volume system between 20 and 220 °C for a wide range of reactant ratios. The order of reaction with respect to hydrogen was one and nearly independent of temperature. While the order of reaction with respect to methylacetylene over nickel catalyst was slightly negative and temperature dependent, it was always positive and nearly independent of temperature for copper and copper-rich alloys. Selectivity was independent of initial hydrogen pressure for nickel and copper only; for others it decreased rapidly with increasing hydrogen pressure. The overall activation energy varied between 9 and 21.2 kcal/g mole. Selectivity and extent of polymerization increased with increasing amount of copper in the alloy.

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Evaluation of the Lower Punctum Parameters and Morphology Using Spectral Domain Anterior Segment Optical Coherence Tomography

Journal of Ophthalmology ◽

10.1155/2015/591845 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Riham S. H. M. Allam ◽

Rania A. Ahmed

Keyword(s):

Optical Coherence Tomography ◽

Anterior Segment ◽

Normal Subjects ◽

Cross Sectional Study ◽

Spectral Domain ◽

Outer Diameter ◽

Optical Coherence ◽

Cross Sectional ◽

Air Bubble ◽

Inner Diameter

Purpose. To study features of the lower punctum in normal subjects using spectral domain anterior segment optical coherence tomography (SD AS-OCT).Methods. Observational cross-sectional study that included 147 punctae (76 subjects). Punctae were evaluated clinically for appearance, position, and size. AS-OCT was used to evaluate the punctal shape, contents, and junction with the vertical canaliculus. Inner and outer diameters as well as depth were measured.Results. 24 males and 52 females (mean age44±14.35 y) were included. Lower punctum was perceived by OCT to be an area with an outer diameter (mean412.16±163 μm), inner diameter (mean233.67±138.73 μm), and depth (mean251.7±126.58 μm). The OCT measured outer punctum diameter was significantly less than that measured clinically (P: 0.000). Seven major shapes were identified. The junction with the vertical canaliculus was detectable in 44%. Fluid was detected in 34%, one of which had an air bubble; however, 63% of punctae showed no contents and 4% had debris.Conclusions. AS-OCT can be a useful tool in understanding the anatomy of the punctum and distal lacrimal system as well as tear drainage physiology. Measuring the punctum size may play a role in plugs fitting.

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STUDY OF MUTAGENIC ACTIVITY NANO- AND MICROPARTICLES IN THE AMES TEST (SALMONELLA / MICROSOME)

Hygiene and Sanitation ◽

10.18821/0016-9900-2019-98-4-455-460 ◽

2019 ◽

Vol 98 (4) ◽

pp. 455-460

Author(s):

Lyudmila V. Akhaltseva ◽

V. S. Zhurkov ◽

L. P. Sycheva ◽

O. N. Savostikova ◽

A. V. Alekseeva

Keyword(s):

Carbon Nanotubes ◽

Ames Test ◽

Mutagenic Activity ◽

Dose Range ◽

Gene Mutations ◽

Outer Diameter ◽

Multi Walled Carbon Nanotubes ◽

Inner Diameter ◽

Substitution Mutations ◽

Walled Carbon Nanotubes

Introduction. One of the important steps in assessing the nanoparticles (NP) safety is the analysis of mutagenic activity, including the evaluation of gene, chromosomal, and genomic mutations. Material and methods. The purpose of this investigation is to study the ability of different NP aqueus suspensions and the same compounds in microforms to unduce gene mutations in Salmonella/microsome test (Ames test). Anatase titanium dioxide NP coated with simethicone (33.16 ± 16.7 nm, 5-50000 μg/ml), magnetite NP coated with silicate (10 nm, 0.92-575 μg/ml), silver NP coated with аrabian gum (14 ± 0.2 nm, 5-50000 μg/ml), aluminum hydroxide nanofibres (50-70 nm, 24-3000 μg/ml) and multi-walled carbon nanotubes (Taunit MWСNTs, outer diameter 15-40 nm, inner diameter 3-8 nm, length 2 and more microns, 5-50000 μg/ml). In parallel, the mutagenic activity of equivalent microparticles was evaluated in experiments. Ames test (Salmonella/microsomes) registers gene mutations induced by a different mechanism of action, in the variant with preincubation. A set of Salmonella typhimurium indicator strains: TA 100 (base pair substitution mutations), TA 98 and TA 97 (mutations of the frameshift type of the genetic code) were used. Using addition the S9 microsomal activating mixture during the experiment makes it is possible to determine the effect not only of the substances themselves, but also of their metabolites. Conclusion. The investigated nanomaterials as well as their micro analogs in the studied dose range did not induce gene mutations in the Ames test both in presence and absence microsomal activating mixture.

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C60 fullerene tubes as removable templates

Journal of Materials Research ◽

10.1557/jmr.2006.0066 ◽

2006 ◽

Vol 21 (2) ◽

pp. 529-534 ◽

Cited By ~ 22

Author(s):

Jun-ichi Minato ◽

Kun'ichi Miyazawa

Keyword(s):

Methyl Alcohol ◽

Isopropyl Alcohol ◽

Optical Observations ◽

C60 Fullerene ◽

Outer Diameter ◽

Solution Deposition ◽

Transmission Electron ◽

Inner Diameter ◽

Ultrasonic Pulverization ◽

Capillary Attraction

Crystalline microtubes (inner diameter 240–2100 nm) consisting of C60 fullerene molecules were prepared in the mixture of C60-saturated pyridine and isopropyl alcohol kept at 0 °C. Characterization by transmission electron microscopy showed a linear relationship between the outer diameter and the inner diameter for the C60 fullerene tubes. Optical observations suggested that the specimens already had tubular structure when they were grown in the solution. Deposition of guest crystals inside the C60 fullerene tubes was performed by the following procedure: (i) ultrasonic pulverization to obtain the C60 fullerene tubes with open ends, (ii) absorption of methyl alcohol solution of KBr into the tubes by the capillary attraction, and (iii) evaporation of methyl alcohol to precipitate KBr inside the tubes. Columnar KBr crystals were then obtained by dissolving the fullerene tube walls in toluene.

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