Development of Silicon Nanoparticle Production Technology using a CO₂ Laser-assisted Carbothermal Reduction Process

2021 ◽  
Vol 30 (4) ◽  
pp. 253-258
Author(s):  
Hakju Lee ◽  
Seunghwan Leea ◽  
Seongbeom Kim
Keyword(s):  
Production Technology ◽  
Carbothermal Reduction ◽  
Reduction Process ◽  
Silicon Nanoparticle ◽  
Co Laser ◽  
Nanoparticle Production

scholarly journals Ultrafast carbothermal reduction of silica to silicon using a CO2 laser beam

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Seok-Ho Maeng ◽  
Hakju Lee ◽  
Min Soo Park ◽  
Suhyun Park ◽  
Jaeki Jeong ◽  
...  
Keyword(s):  
Carbon Black ◽  
Laser Beam ◽  
Carbothermal Reduction ◽  
Gas Flow ◽  
Crystalline Silicon ◽  
Reduction Process ◽  
Reaction Chamber ◽  
Raman Shift ◽  
Influence Of Process Parameters ◽  
Laser Beam Intensity

AbstractWe report the extraction of silicon via a carbothermal reduction process using a CO2 laser beam as a heat source. The surface of a mixture of silica and carbon black powder became brown after laser beam irradiation for a few tens of seconds, and clear peaks of crystalline silicon were observed by Raman shift measurements, confirming the successful carbothermal reduction of silica. The influence of process parameters, including the laser beam intensity, radiation time, nitrogen gas flow in a reaction chamber, and the molar ratios of silica/carbon black of the mixture, on the carbothermal reduction process is explained in detail.

scholarly journals Titanium Carbide Nanocrystals Synthesized from a Metatitanic Acid-Sucrose Precursor via a Carbothermal Reduction

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Hyunho Shin ◽  
Jun-Ho Eun
Keyword(s):  
Process Control ◽  
Titanium Carbide ◽  
Specific Surface ◽  
Surface Area ◽  
Pore Volume ◽  
Carbothermal Reduction ◽  
Crystal Size ◽  
Reduction Process ◽  
Specific Pore Volume ◽  
Metatitanic Acid

A TiC powder is synthesized from a micron-sized mesoporous metatitanic acid-sucrose precursor (precursor M) by a carbothermal reduction process. Control specimens are also prepared using a nanosized TiO2-sucrose precursor (precursor T) with a higher cost. When synthesized at 1500°C for 2 h in flowing Ar, the characteristics of the synthesized TiC from precursor M are similar to those of the counterpart from precursor T in terms of the crystal size (58.5 versus 57.4 nm), oxygen content (0.22 wt% versus 0.25 wt%), and representative sizes of mesopores: approximately 2.5 and 19.7–25.0 nm in both specimens. The most salient differences of the two specimens are found in the TiC from precursor M demonstrating (i) a higher crystallinity based on the distinctive doublet peaks in the high-two-theta XRD regime and (ii) a lower specific surface area (79.4 versus 94.8 m2/g) with a smaller specific pore volume (0.1 versus 0.2 cm3/g) than the counterpart from precursor T.

High surface area mesoporous SiC synthesized via nanocasting and carbothermal reduction process

2005 ◽  
Vol 40 (18) ◽  
pp. 5091-5093 ◽  
Author(s):  
AN-HUI LU ◽  
WOLFGANG SCHMIDT ◽  
WOLFGANG KIEFER ◽  
FERDI SCHÜTH
Keyword(s):  
Surface Area ◽  
Carbothermal Reduction ◽  
High Surface ◽  
High Surface Area ◽  
Reduction Process

On the carbo-thermal reduction of silica for carbon nano-fibre formation via CVD

2011 ◽  
Vol 1284 ◽  
Author(s):  
Alicja Bachmatiuk ◽  
Felix Börrnert ◽  
Imad Ibrahim ◽  
Bernd Büchner ◽  
Mark H. Rümmeli
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Carbothermal Reduction ◽  
Carbon Nanostructures ◽  
Reduction Process ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Thermal Reduction ◽  
Fibre Formation ◽  
Quartz Substrates

ABSTRACTThe formation of carbon nanostructures using silica nanoparticles from quartz substrates as a catalyst in an aerosol assisted chemical vapor deposition process was examined. The silica particles are reduced to silicon carbide via a carbothermal reduction process. The recyclability of the explored quartz substrates is also presented. The addition of triethyl borate improves the efficiency of the carbothermal reduction process and carbon nanotubes formation. Moreover, the addition of hydrogen during the chemical vapor deposition leads to the helical carbon nanostructures formation.

Experimental process and kinetic behavior of carbothermal reduction of lithium cobaltate as a cathode for waste lithium batteries

2021 ◽  
Vol 11 (12) ◽  
pp. 1988-1996
Author(s):  
Cao Zhi-Kang ◽  
Li Ji-Dong ◽  
Li Zhen ◽  
Wang Xue-Lian ◽  
Yue Ling-Feng
Keyword(s):  
Cathode Material ◽  
Lithium Ion Batteries ◽  
Calcination Temperature ◽  
Carbothermal Reduction ◽  
High Efficiency ◽  
Diffusion Mechanism ◽  
Reduction Rate ◽  
Reduction Process ◽  
Lithium Ion ◽  
Lithium Cobaltate

Lithium cobaltate as a cathode material has great recycling value in the recycling process of spent lithium-ion batteries, To promote the thermal reduction process of lithium cobaltate and recover high-value cobalt and lithium metals, we studied the process of lithium cobaltate reduction by carbon under different conditions and its thermal reaction kinetics. The effects of calcination temperature, raw material ratio, pelletizing pressure and holding time on the reduction rate of lithium cobaltate were investigated by controlling variables. The results showed that the optimum experimental conditions were as follows: mass ratio of carbon and lithium cobaltate was 1:1, pelletizing pressure was 45 MPa, calcination temperature was 800 °C, and calcination time was 6 h. Under these conditions, lithium cobaltate could be converted into cobalt and lithium carbonate, and the recovery rate of cobalt and lithium was 97% and 95%, respectively. A kinetic study on the carbothermal reduction reaction of LiCoO2 showed that the average activation energy of the carbothermal reaction of LiCoO2 under nitrogen protection was 280.6851 kJ/mol, and the mechanism model of the thermal decomposition reaction of LiCoO2 was controlled by chemicals, showing a deceleration curve. The corresponding process conforms to the threedimensional diffusion mechanism of the inverse Jander equation, which lays a theoretical foundation for the high-efficiency separation and recovery of LiCoO2 cathode material for waste lithium-ion batteries.

Study on in-Situ Preparation and Growth Mechanism of TiCxN1-x Whiskers

2011 ◽  
Vol 197-198 ◽  
pp. 617-622
Author(s):  
Xue Wen Chong ◽  
Chuan Zhen Huang ◽  
Liang Xu ◽  
Bin Zou ◽  
Han Lian Liu ◽  
...  
Keyword(s):  
Growth Mechanism ◽  
Carbothermal Reduction ◽  
Reduction Process ◽  
Vapor Liquid Solid ◽  
Mixed Powder ◽  
Vapor Liquid Solid Mechanism ◽  
Vapor Liquid

TiCxN1-x whiskers were prepared using TiO2 and carbon mixed powder as the starting powder at the atmosphere of nitrogen by the carbothermal reduction process. NaCl and NiCl2 were added into the starting powder as the cosolvent and growth adds of impurities, respectively. An effect of the content of TiO2 and carbon in the starting powder on the TiCxN1-x whiskers was investigated. It is found from SEM and XRD observations that three types of TiCx N1-x whiskers are obtained when the different mol ratios of C and Ti are applied. The growth of whiskers is not only urged by the droplet on the top of whiskers, but also initiated by the helical dislocations. The growth of TiCxN1-x whiskers is controlled by the vapor-liquid-solid mechanism as well as vapor-solid mechanism.

A facile pathway to prepare VO2 and V2O3 powders via a carbothermal reduction process

2018 ◽  
Vol 265 ◽  
pp. 299-305 ◽  
Author(s):  
Yue-Dong Wu ◽  
Guo-Hua Zhang ◽  
Yu Wang ◽  
Rui Xu ◽  
Kuo-Chih Chou
Keyword(s):  
Carbothermal Reduction ◽  
Reduction Process

scholarly journals Recycling of Alkaline Batteries via a Carbothermal Reduction Process

Batteries ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 35 ◽  
Author(s):  
Selçuk Yeşiltepe ◽  
Mehmet Buğdaycı ◽  
Onuralp Yücel ◽  
Mustafa Şeşen
Keyword(s):  
Carbothermal Reduction ◽  
Reduction Process ◽  
Economic Benefits ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Alkaline Batteries ◽  
Primary Battery ◽  
Battery Recycling ◽  
Steel Container ◽  
Manganese Monoxide

Primary battery recycling has important environmental and economic benefits. According to battery sales worldwide, the most used battery type is alkaline batteries with 75% of market share due to having a higher performance than other primary batteries such as Zn–MnO2. In this study, carbothermal reduction for zinc oxide from battery waste was completed for both vacuum and Ar atmospheres. Thermodynamic data are evaluated for vacuum and Ar atmosphere reduction reactions and results for Zn reduction/evaporation are compared via the FactSage program. Zn vapor and manganese oxide were obtained as products. Zn vapor was re-oxidized in end products; manganese monoxide and steel container of batteries are evaluated as ferromanganese raw material. Effects of carbon source, vacuum, temperature and time were studied. The results show a recovery of 95.1% Zn by implementing a product at 1150 °C for 1 h without using the vacuum. The residues were characterized by Atomic Absorption Spectrometer (AAS) and X-ray Diffraction (XRD) methods.

scholarly journals Influence of Desulfurization with Fe2O3 on the Reduction of Nickel Converter Slag

Materials ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2423
Author(s):  
Guangsheng Wei ◽  
Yun Wang ◽  
Rong Zhu ◽  
Lingzhi Yang
Keyword(s):  
Metal Oxides ◽  
Sulfur Content ◽  
Carbothermal Reduction ◽  
Converter Slag ◽  
Reduction Process ◽  
Reduction Reaction ◽  
Copper Recovery ◽  
Desulfurization Rate ◽  
Residual Sulfur ◽  
Nickel Converter

Generally in the nickel converter slag, metals are mainly in the form of sulfides, which are difficult to separate from slag. Although metal oxides in the slag, such as NiO, CoO, and Cu2O, are easily reduced into metal using carbon, the presence of sulfur inhibits the reduction reaction. In this study, the addition of Fe2O3 to nickel converter slag produced desulfurized slag, which enhanced the carbothermal reduction process. Increasing the desulfurization rate promoted the conversion of sulfides into oxides in slag, which significantly increased the activity of NiO, Cu2O, and Fe2O3. However, the residual sulfur content had no significant effect on the activity of FeO and CoO, due to the high initial FeO content and cobalt existing mainly in the form of oxides. The optimum addition of Fe2O3 was 15.0 g per 100 g nickel slag, while the desulfurization ratio was 36.84% and the rates of nikel, cobalt and copper recovery were 95.33%, 77.73%, and 73.83%, respectively.

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