Forming thermodynamics, structure, and electrical conductivity of TiC O compounds fabricated through the carbothermal reduction process

2022 ◽  
Vol 892 ◽  
pp. 162201
Author(s):  
Wenyuan Long ◽  
Feng Gao ◽  
Dengpeng Wang ◽  
Benshan Zou ◽  
Xianran Wang ◽  
...  
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Seok-Ho Maeng ◽  
Hakju Lee ◽  
Min Soo Park ◽  
Suhyun Park ◽  
Jaeki Jeong ◽  
...  

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.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Hyunho Shin ◽  
Jun-Ho Eun

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.


2005 ◽  
Vol 40 (18) ◽  
pp. 5091-5093 ◽  
Author(s):  
AN-HUI LU ◽  
WOLFGANG SCHMIDT ◽  
WOLFGANG KIEFER ◽  
FERDI SCHÜTH

2011 ◽  
Vol 1284 ◽  
Author(s):  
Alicja Bachmatiuk ◽  
Felix Börrnert ◽  
Imad Ibrahim ◽  
Bernd Büchner ◽  
Mark H. Rümmeli

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.


Author(s):  
Yu. V. Gamin ◽  
B. A. Romantsev ◽  
A. N. Pashkov ◽  
P. V. Patrin ◽  
I. A. Bystrov ◽  
...  

The article proposes a process for obtaining semi-finished products in the form of pipes made of copper alloys for electrical applications using the screw rolling method. The paper presents the results of experimental piercing and rolling of pipe samples made of Cu–0.75Cr copper alloy billets with a diameter of 45 mm. The 43.5×10.0 mm samples obtained after piercing using a two-roll screw rolling mill had exact geometrical dimensions: outer diameter deviation at the front end was up to 1 %, at the back end – up to 2.4 %; relative variation in wall thickness at the front end was 0.3÷0.5 %, at the rear end – 0.5÷1.0 %. Then pierced pipe samples were rolled using a three-roll radial-shear rolling (RSR) mini mill with a different total degree of reduction – samples were obtained with an outer diameter of 30, 25 and 18 mm. The reduction process was analyzed from the point of view of internal hole stability and deformation. In case of 30 % relative reduction of the outer diameter, rolling without a mandrel is accompanied by wall thickening. In this case, inner diameter deviations are within acceptable limits. The experiments on obtaining samples from the Cu–0.75Cr alloy by screw piercing and reduction in the RSR mill show that this scheme can be implemented in principle in industry. At the same time it is necessary to define more exactly deformation parameters (degree of deformation, choice of reduction scheme) to obtain a quality product. Various options for heat treatment (HT) of the obtained pipe samples and the effect of the HT method on electrical conductivity and hardness are considered. Samples after piercing had a conductivity of 59.3 % IACS. The maximum electrical conductivity of 76.7 % IACS was obtained on samples after quenching from a temperature of 1020 °C and aging at 450 °C for 3 h. The results of the work show the fundamental possibility of obtaining semi-finished products from copper alloys for electrical purposes using the screw rolling method.


2021 ◽  
Vol 11 (12) ◽  
pp. 1988-1996
Author(s):  
Cao Zhi-Kang ◽  
Li Ji-Dong ◽  
Li Zhen ◽  
Wang Xue-Lian ◽  
Yue Ling-Feng

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.


2011 ◽  
Vol 197-198 ◽  
pp. 617-622
Author(s):  
Xue Wen Chong ◽  
Chuan Zhen Huang ◽  
Liang Xu ◽  
Bin Zou ◽  
Han Lian Liu ◽  
...  

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.


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

Batteries ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 35 ◽  
Author(s):  
Selçuk Yeşiltepe ◽  
Mehmet Buğdaycı ◽  
Onuralp Yücel ◽  
Mustafa Şeşen

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.


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