Catalytic Effect of Iron on the Carbon Gasification Reaction and Its Rate Constants in Iron-Carbon Composite Pellet

There are two contents of this article. The first is briefly to review the experiment research on the catalysis mechanism of Carbon Gasification Reaction-CGR(C+CO2=2CO) from 60s -90s. The results show that the catalytic phenomenon is physical phenomenon rather than chemical, and the catalyst does not participate in the chemical reaction. The catalytic activity and selectivity of catalyst are related to the electronegativity or energy level of the catalyst. The second is to clarify the applications of CGR for save mankind. The lime is first proposed to capture CO2 in flue gas of power plant. The lime can be recycled. The coal is used to convert CO2 from cement steel produce into CO, producing both energy and lime and iron. The capture CO2 is used to treat waste such as firewood and plastic, eliminate white pollution. The author considers that using the CGR which has been used for a long time can solve the three problems which people worry about: energy exhaustion, environmental pollution and climate crisis.

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Catalytic Effect of Fe2O3, MnO2and MgO on the Gasification Reaction of Biomass Char

TMS2015 Supplemental Proceedings ◽

10.1002/9781119093466.ch103 ◽

2015 ◽

pp. 849-854

Author(s):

Hai-Bin Zuo ◽

Wei-Wei Geng ◽

Guang-Wei Wang ◽

Jian-Liang Zhang

Keyword(s):

Catalytic Effect ◽

Biomass Char ◽

Gasification Reaction

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Kinetics of the Volume Shrinkage of a Magnetite/Carbon Composite Pellet during Solid-State Carbothermic Reduction

Metals ◽

10.3390/met8121050 ◽

2018 ◽

Vol 8 (12) ◽

pp. 1050 ◽

Cited By ~ 3

Author(s):

Guang Wang ◽

Jingsong Wang ◽

Qingguo Xue

Keyword(s):

Activation Energy ◽

Solid State ◽

Apparent Activation Energy ◽

Carbothermic Reduction ◽

Iron Ore ◽

Carbon Composite ◽

Volume Shrinkage ◽

Reduction Temperature ◽

Iron Particles ◽

Composite Pellet

The volume shrinkage evolution of a magnetite iron ore/carbon composite pellet during solid-state isothermal reduction was investigated. For the shrinkage, the apparent activation energy and mechanism were obtained based on the experimental results. It was found that the volume shrinkage highly depended on the reduction temperature and on dwell time. The volume shrinkage of the pellet increased with the increasing reduction temperature, and the rate of increment was fast during the first 20 min of reduction. The shrinkage of the composite pellet was mainly due to the weight loss of carbon and oxygen, the sintering growth of gangue oxides and metallic iron particles, and the partial melting of the gangue phase at high temperature. The shrinkage apparent activation energy was different depending on the time range. During the first 20 min, the shrinkage apparent activation energy was 51,313 J/mol. After the first 20 min, the apparent activation energy for the volume shrinkage was only 19,697 J/mol. The change of the reduction rate-controlling step and the automatic sintering and reconstruction of the metallic iron particles and gangue oxides in the later reduction stage were the main reasons for the aforementioned time-dependent phenomena. The present work could provide a unique scientific index for the illustration of iron ore/carbon composite pellet behavior during solid-state carbothermic reduction.

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Exergy Destruction Mechanism of Coal Gasification by Combining the Kinetic Method and the Energy Utilization Diagram

Journal of Energy Resources Technology ◽

10.1115/1.4036957 ◽

2017 ◽

Vol 139 (6) ◽

Cited By ~ 5

Author(s):

Handong Wu ◽

Sheng Li ◽

Lin Gao

Keyword(s):

Chemical Reactions ◽

Coal Gasification ◽

Kinetic Method ◽

Steam Gasification ◽

Energy Utilization ◽

Exergy Destruction ◽

Steam Content ◽

Carbon Gasification ◽

Destruction Mechanism ◽

Gasification Reaction

Gasification is the core unit of coal-based production systems and is also the site where one of the largest exergy destruction occurs. This paper reveals the exergy destruction mechanism of carbon gasification through a combined analysis of the kinetic method and the energy utilization diagram (EUD). Instead of a lumped exergy destruction using the traditional “black-box” and other models, the role of each reaction in carbon gasification is revealed. The results show that the exergy destruction caused by chemical reactions accounts for 86.3% of the entire carbon gasification process. Furthermore, approximately 90.3% of exergy destruction of chemical reactions is caused by the exothermal carbon partial oxidation reaction (reaction 1), 6.0% is caused by the carbon dioxide gasification reaction (reaction 2), 2.4% is caused by the steam gasification reaction (reaction 3), and 1.3% is caused by other reactions under the base condition. With increasing O2 content α and decreasing steam content β, the proportion of exergy destruction from reaction 1 decreases due to the higher gasification temperature (a higher energy level of energy acceptor in EUD), while the proportions of other reactions increase. This shows that the chemical efficiency is optimal when the extent of reactions 1 and 3 is equal and the shift reaction extent approaches zero at the same time.

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Electrochemical impedance characterization on catalytic carbon gasification reaction process

Fuel ◽

10.1016/j.fuel.2014.11.095 ◽

2015 ◽

Vol 143 ◽

pp. 499-503 ◽

Cited By ~ 1

Author(s):

Xiankai Yu ◽

Yixiang Shi ◽

Ningsheng Cai

Keyword(s):

Electrochemical Impedance ◽

Reaction Process ◽

Carbon Gasification ◽

Gasification Reaction ◽

Impedance Characterization

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Influence of CaO-SiO2-Al2O3 Ternary Oxide System on the Reduction Behavior of Carbon Composite Pellet: Part II. Morphological Properties

Metallurgical and Materials Transactions B ◽

10.1007/s11663-013-9932-7 ◽

2013 ◽

Vol 44 (6) ◽

pp. 1390-1397 ◽

Cited By ~ 10

Author(s):

Hyunsik Park ◽

Veena Sahajwalla

Keyword(s):

Carbon Composite ◽

Oxide System ◽

Morphological Properties ◽

Ternary Oxide ◽

Reduction Behavior ◽

Composite Pellet ◽

Ternary Oxide System

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Numerical simulation and parameters optimisation of direct reduction process of iron ore–carbon composite pellet

Mineral Processing and Extractive Metallurgy ◽

10.1179/1743285514y.0000000076 ◽

2014 ◽

Vol 124 (1) ◽

pp. 27-34 ◽

Cited By ~ 5

Author(s):

Ying Liu ◽

Fuyong Su ◽

Zhi Wen ◽

Zhi Li ◽

Haiquan Yong ◽

...

Keyword(s):

Numerical Simulation ◽

Iron Ore ◽

Direct Reduction ◽

Reduction Process ◽

Carbon Composite ◽

Composite Pellet ◽

Direct Reduction Process

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Carbothermic Reduction of Zinc Ferrite by Microwave Heating

High Temperature Materials and Processes ◽

10.1515/htmp-2012-0170 ◽

2013 ◽

Vol 32 (5) ◽

pp. 485-491 ◽

Cited By ~ 3

Author(s):

Xin Wang ◽

Shao-Hua Ju ◽

C. Srinivasakannan ◽

Da-Jin Yang ◽

Jin-Hui Peng

Keyword(s):

Particle Size ◽

Microwave Power ◽

Carbothermic Reduction ◽

Decomposition Temperature ◽

Mechanism Of Formation ◽

Carbon Gasification ◽

Gasification Reaction ◽

Kinetics Of ◽

Hsc Chemistry ◽

Equilibrium Calculations

AbstractThe kinetics of carbothermic reduction of ZnFe2O4 in the temperature range 823–1223 K, was investigated in a microwave reactor. The mechanism of formation of ZnO and Fe3O4/FeO by decomposition of ZnFe2O4 was explained using the equilibrium calculations and thermodynamics analysis using HSC chemistry software 6.0. In addition the effect of parameters such as the decomposition temperature, C/ZnFe2O4 ratio, particle size and microwave power were assessed on the decomposition kinetics. Zn recovery as high as 98.83% could be achieved at a decomposition temperature of 1023 K, C/ZnFe2O4 ratio of 1:3, particle size of +74–61 µm and microwave power of 1200 W. The kinetics of decomposition was found to be carbon gasification reaction controlled, with the activation energy of 39.21 kJ/mol.

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Experimental Study on Strengthening Carbothermic Reduction of Vanadium-Titanium-Magnetite by Adding CaF2

Minerals ◽

10.3390/min10030219 ◽

2020 ◽

Vol 10 (3) ◽

pp. 219 ◽

Cited By ~ 1

Author(s):

Xiangdong Xing ◽

Yueli Du ◽

Jianlu Zheng ◽

Yunfei Chen ◽

Shan Ren ◽

...

Keyword(s):

Carbothermic Reduction ◽

Reduction Rate ◽

Reduction Process ◽

Complex Compounds ◽

Carbon Gasification ◽

Promotive Effect ◽

Mass Fractions ◽

Vanadium Titanium ◽

Gasification Reaction ◽

Titanium Magnetite

The effects and reduction mechanisms of carbothermic reduction of vanadium–titanium–magnetite were studied by adding various mass fractions of CaF2 ranging from 0%, 1%, 3%, 5% to 7%. The results showed that the proper CaF2 addition could strengthen the carbothermic reduction of vanadium–titanium–magnetite while the excessive amounts will weaken the promotive effect, hence the appropriate dosage was determined to be 3 mass%. The CaF2 was favorable for the carbon gasification reaction, where it increased the partial pressure of CO inside briquette and caused the lattice distortion of vanadium–titanium–magnetite. The reaction improved the reduction process and accelerated the reduction rate. The appearance of 3CaO·2SiO2·CaF2 and other complex compounds with low melting point facilitated the aggregation and growth of the slag and the iron, which increased the concentration of iron grains and the aggregation level of the slag.

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Structure evolution of a magnetite iron ore/carbon composite pellet during solid-state reduction under microwave heating

Journal of Science and Technology of Metal ◽

10.52923/vmfs.jstm.102021.98.01 ◽

2021 ◽

Vol 98 ◽

Author(s):

Cuong Phung Kien ◽

◽

Dung Ngo Quoc ◽

Anh Do Thi ◽

Hieu Nguyen Sy ◽

...

Keyword(s):

Solid State ◽

Microwave Heating ◽

Metallic Iron ◽

Iron Ore ◽

Reference Sample ◽

Carbon Composite ◽

Structure Evolution ◽

Firing Time ◽

State Reduction ◽

Composite Pellet

In the present study, the structure evolution under direct reduction of a Minh-Son magnetite iron ore/carbon composite pellets in a microwave-heating kiln under different microwave wattage of 60 and 90 % (with the firing time from 15 to 120 min.) was investigated. The microstructure of the pellets was characterized by scanning electron microscopy coupled with energy dispersive spectroscopy and X-ray diffraction (XRD). The phase formation was indexed using MDI Jade from the peaks matching the reference sample. At the microwave’s wattage of 60 %: the wustite (FeO) has appeared after firing time of 60 min., the metallic iron and fayalite have appeared in the reduced samples after firing time of 90 min. to 120 min. with retained phases of Fe203, Fe304, FeO and Si02– While at the microwave’s wattage of 90 %, the metallic iron has appeared in the reduced samples after firing time of 30 min. to 120 min and fayalite has appeared in the reduced samples after firing time of 60 min. to 120 min. The final reduced pellet, under microwave’s wattage of 90 % and firing time of 120 min., shows the only phases of metallic iron and fayalite according to the XRD resolution. The present work could provide a scientific understanding to illustrate iron ore/carbon composite pellet behavior during solid-state carbothermic reduction under a microwave-heating.

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