scholarly journals Methane Conversion over Vacuum Carbon Black: Influence of Hydrogen

2017 ◽  
Vol 3 (3) ◽  
pp. 163 ◽  
Author(s):  
S.D. Kushch ◽  
V.E. Muradyan ◽  
N.S. Kuyunko
Keyword(s):  
Carbon Black ◽  
Methane Conversion ◽  
Heterogeneous Reaction ◽  
Pyrolytic Carbon ◽  
Conversion Degree ◽  
Carbon Formation ◽  
Initial Concentration ◽  
Temperature Range ◽  
The One ◽  
Methane Pyrolysis

<p>Methane pyrolysis over vacuum carbon black has been studied in the temperature range 550–1000 °C. The methane conversion degree and selectivity with respect to ethene and propene do not depend on the initial concentration of methane <em>i.e. </em>the process order with respect to methane is first. The selectivity with respect to pyrolytic carbon is antibate to the methane initial concentration. Hydrogen introduced to methane inhibits formation of pyrolytic carbon and aromatics especially in methane pyrolysis. The methane conversion degree in pyrolysis of methane/hydrogen mixture is inversely proportional to the initial concentration of hydrogen while the selectivity with respect to ethene being symbate to the one. A hypothesis on the reason of inhibition of pyrolytic carbon formation by hydrogen is proposed. Methane pyrolysis is a homogeneous-heterogeneous reaction up to 850°C, but homogeneous reaction is prevalent at the temperature range of maximal selectivity with respect to alkenes.</p>

Kinetics of methane pyrolysis under conditions of pyrolytic carbon formation

Carbon ◽  
1974 ◽  
Vol 12 (4) ◽  
pp. 391-403 ◽  
Author(s):  
K.I. Makarov ◽  
V.K. Pechik
Keyword(s):  
Pyrolytic Carbon ◽  
Carbon Formation ◽  
Kinetics Of ◽  
Methane Pyrolysis

Wet compounding with pyrolytic carbon black from waste tyre for manufacture of new tyre – A mini review

2021 ◽  
pp. 0734242X2110047
Author(s):  
Junqing Xu ◽  
Jiaxue Yu ◽  
Wenzhi He ◽  
Juwen Huang ◽  
Junshi Xu ◽  
...  
Keyword(s):  
Carbon Black ◽  
Pyrolytic Carbon ◽  
Research Progress ◽  
Rubber Matrix ◽  
Innovative Technology ◽  
Nano Materials ◽  
Natural Rubber Composites ◽  
Waste Tyres ◽  
Dry Mixing ◽  
Waste Tyre

Pyrolysis offers a more focused alternative to waste tyres treatment. Pyrolytic carbon black (CBp), the main product of waste tyre pyrolysis, and its modified species can be applied to tyre manufacturing realizing its high-value utilization. Modified pyrolytic carbon black/natural rubber composites prepared by a wet compounding (WC) and latex mixing process have become an innovative technology route for waste tyre remanufacturing. The main properties and applications of CBp reported in recent years are reviewed, and the main difficulties affecting its participation in tyre recycling are pointed out. The research progress of using WC technology to replace dry mixing manufacturing of new tyres is summarized. Through literature data and comparative studies, this paper points out that the characteristic of high ash content can be well utilized if CBp is applied to tyre manufacturing. This mini-review proposes a new method for high-value utilization of CBp. The composite mixing of CBp and carbon nano-materials under wet conditions is conducive to the realization of their good dispersion in the rubber matrix. This provides a new idea for customer resource integration and connection of industry development between the tyre production industry and waste tyre disposal management.

scholarly journals Upgrading pyrolytic residue from waste tires to commercial carbon black

2018 ◽  
Vol 36 (5) ◽  
pp. 436-444 ◽  
Author(s):  
Xue Zhang ◽  
Hengxiang Li ◽  
Qing Cao ◽  
Li’e Jin ◽  
Fumeng Wang
Keyword(s):  
Carbon Black ◽  
Value Added ◽  
Pyrolytic Carbon ◽  
Ultrasonic Waves ◽  
Added Value ◽  
Infrared Spectrometry ◽  
Raman Spectrometry ◽  
X Ray ◽  
Waste Tires ◽  
Commercial Carbon

The managing and recycling of waste tires has become a worldwide environmental challenge. Among the different disposal methods for waste tires, pyrolysis is regarded as a promising route. How to effectively enhance the added value of pyrolytic residue (PR) from waste tires is a matter of great concern. In this study, the PRs were treated with hydrochloric and hydrofluoric acids in turn under ultrasonic waves. The removal efficiency for the ash and sulfur was investigated. The pyrolytic carbon black (PCB) obtained after treating PR with acids was analyzed by X-ray fluorescence spectrophotometry, Fourier transform infrared spectrometry, X-ray diffractometry, laser Raman spectrometry, scanning electron microscopy, thermogravimetric (TG) analysis, and physisorption apparatus. The properties of PCB were compared with those of commercial carbon black (CCB) N326 and N339. Results showed PRs from waste tires were mainly composed of carbon, sulfur, and ash. The carbon in PCB was mainly from the CCB added during tire manufacture rather than from the pyrolysis of pure rubbers. The removal percentages for the ash and sulfur of PR are 98.33% (from 13.98 wt % down to 0.24 wt %) and 70.16% (from 1.81 wt % down to 0.54 wt %), respectively, in the entire process. The ash was mainly composed of metal oxides, sulfides, and silica. The surface properties, porosity, and morphology of the PCB were all close to those of N326. Therefore, PCB will be a potential alternative of N326 and reused in tire manufacture. This route successfully upgrades PR from waste tires to the high value-added CCB and greatly increases the overall efficiency of the waste tire pyrolysis industry.

Pyrolytic carbon black-derived porous carbon with spherical skeleton as recovered and enduring electrode material for supercapacitor

2021 ◽  
Vol 44 ◽  
pp. 103372
Author(s):  
Guosai Jiang ◽  
Jun Guo ◽  
Yanzhi Sun ◽  
Xiaoguang Liu ◽  
Junqing Pan
Keyword(s):  
Carbon Black ◽  
Electrode Material ◽  
Porous Carbon ◽  
Pyrolytic Carbon

scholarly journals On the Mechanism of Methane Conversion in the Nonсatalytic Processes of Its Thermal Pyrolysis and Steam and Carbon Dioxide Reforming

2021 ◽  
Author(s):  
E. Busillo ◽  
V. I. Savchenko ◽  
V. S. Arutyunov
Keyword(s):  
Carbon Dioxide ◽  
Methane Conversion ◽  
Carbon Dioxide Reforming ◽  
Temperature Range ◽  
Thermal Pyrolysis ◽  
First Order Kinetics ◽  
Initial Stage ◽  
Conversion Of Methane ◽  
Exponential Factors ◽  
Kinetics Of

Abstract A detailed kinetic modeling of the noncatalytic processes of thermal pyrolysis and steam and carbon dioxide reforming of methane revealed almost completely identical kinetics of the methane conversion in these processes. This suggests that, in the temperature range 1400–1800 K, the initial stage of conversion of methane in all these processes is its thermal pyrolysis. The modeling results agree well with the experimental data on methane pyrolysis. For the temperature range examined, the Arrhenius expressions (pre-exponential factors and activation energy) were obtained in the first-order kinetics approximation for the rate of methane conversion in the processes studied. The expressions derived may be useful for making preliminary estimates and carrying out engineering calculations.

scholarly journals Ozone Impacts of Gas-Aerosol Uptake in Global Chemistry Transport Models

2017 ◽  
Author(s):  
Scarlet Stadtler ◽  
David Simpson ◽  
Sabine Schröder ◽  
Domenico Taraborrelli ◽  
Andreas Bott ◽  
...  
Keyword(s):  
East Asia ◽  
Surface Area ◽  
Heterogeneous Reaction ◽  
Photochemical Reactions ◽  
Heterogeneous Reactions ◽  
Transport Models ◽  
Global Pattern ◽  
Temporal Correlations ◽  
The One ◽  
The Impact

Abstract. The impact of six heterogeneous gas-aerosol uptake reactions on tropospheric ozone and nitrogen species was studied using two chemical transport models, EMEP MSC-W and ECHAM-HAMMOZ. Species undergoing heterogeneous reactions in both models include N2O5, NO3, NO2, O3, HNO3 and HO2. Since heterogeneous reactions take place at the aerosol surface area, the modeled surface area density Sa of both models was compared to a satellite product retrieving the surface area. This comparison shows a good agreement in global pattern and especially the capability of both models to capture the extreme aerosol loadings in East Asia. The impact of the heterogeneous reactions was evaluated by the simulation of a reference run containing all heterogeneous reactions and several sensitivity runs. One reaction was turned off in each sensitivity run to compare it with the reference run. The analysis of the sensitivity runs confirms that the globally most important heterogeneous reaction is the one of N2O5. Nevertheless, NO2, HNO3 and HO2 heterogeneous reaction gain relevance particularly in East Asia due to the presence of high NOx concentrations and high Sa in the same region, although ECHAM-HAMMOZ showed much stronger responses than EMEP in this respect. The heterogeneous reaction of O3 itself on dust is of minor relevance compared to the other heterogeneous reactions. The impacts of the N2O5 reactions show strong seasonal variations, with biggest impacts on O3 in spring time when photochemical reactions are active and N2O5 levels still high. Evaluation of the models with northern hemispheric ozone surface observations yields a better agreement of the models with observations in terms of concentration levels, variability, and temporal correlations at most sites when the heterogeneous reactions are incorporated.

scholarly journals Methane pyrolysis in preparation of pyrolytic carbon: Thermodynamic and kinetic analysis by density functional theory

2020 ◽  
Vol 33 (3) ◽  
pp. 1064-1073 ◽  
Author(s):  
Chunxia HU ◽  
He SHEN ◽  
Shouyang ZHANG ◽  
Hejun LI
Keyword(s):  
Density Functional Theory ◽  
Kinetic Analysis ◽  
Density Functional ◽  
Pyrolytic Carbon ◽  
Functional Theory ◽  
Methane Pyrolysis

Scanning UV microspectrophotometry as a tool to study the changes of lignin in hydrothermally modified wood

Holzforschung ◽  
2016 ◽  
Vol 70 (3) ◽  
pp. 215-221 ◽  
Author(s):  
Bruno Andersons ◽  
Guna Noldt ◽  
Gerald Koch ◽  
Ingeborga Andersone ◽  
Anete Meija-Feldmane ◽  
...  
Keyword(s):  
Cell Wall ◽  
Degradation Products ◽  
Middle Lamella ◽  
Temperature Range ◽  
Wood Protection ◽  
Lower Temperature Range ◽  
Lower Temperature ◽  
The One ◽  
S2 Layer ◽  
Uv Microspectrophotometry

Abstract Thermal modification (TM) of wood has occupied a relatively narrow but stable niche as an alternative for chemical wood protection. There are different technological solutions for TM and not all details of their effects on wood tissue have been understood. The one-stage hydrothermal modification (HTM) at elevated vapour pressure essentially changes the wood’s composition and structure. In the present paper, the changes in three hardwood lignins (alder, aspen, and birch) were observed within the cell wall by means of cellular UV microspectrophotometry. The lignin absorbances in the compound middle lamella (CML) of unmodified wood are 1.7- to 2.0-fold higher than those in the fibre S2 layer. The woods were modified in the temperature range from 140 to 180°C, while in the lower temperature range (140°C/1 h), the UV absorbances are little affected. Essential changes occur in the range of 160–180°C and the UV data reflect these by absorbtion changes, while the absorbances at 278 nm rise with factors around 2 more in the S2 layer than in the CML. The absorbance increments are interpreted as polycondensation reactions with furfural and other degradation products of hemicelluloses with the lignin moiety of the cell wall.

The Interaction of Carbon Black with Sulfur, MBT and TMTD in Vulcanization

1961 ◽  
Vol 34 (2) ◽  
pp. 588-599 ◽  
Author(s):  
G. A. Blokh ◽  
Ch. L. Melamed
Keyword(s):  
Experimental Data ◽  
Carbon Black ◽  
Chemical Reactions ◽  
The Other ◽  
Considerable Importance ◽  
Physical Aspect ◽  
Active Centers ◽  
Other Hand ◽  
The One

Abstract The experimental data collected on the interaction of active centers of carbon black with the rubber on the one hand and of the active centers of carbon black with the sulfur and accelerators, and also with the antioxidants, on the other hand, provide a sound basis for belief that the problem of reinforcement of rubber by active fillers in the process of vulcanization cannot be explained from the physical aspect alone. The facts indicate the considerable importance of the chemical reactions between the active groups of carbon black and the compounding ingredients in the course of vulcanization.

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