CIESC Journal ›› 2021, Vol. 72 ›› Issue (4): 2300-2308.DOI: 10.11949/0438-1157.20200981

• Material science and engineering, nanotechnology • Previous Articles     Next Articles

Effect of raw material size on the synthesis of silicon carbide

LU Pengfei1,2(),JIN Zhihao1(),CUI Yanbin2,XU Guangwen1,2,WU Rongcheng2()   

  1. 1.School of Mechanical and Power Engineering,Shenyang University of Chemical Technology,Shenyang 110142, Liaoning,China
    2.State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2020-07-20 Revised:2020-09-29 Online:2021-04-05 Published:2021-04-05
  • Contact: JIN Zhihao,WU Rongcheng

原料粒度对合成碳化硅的影响研究

陆鹏飞1,2(),金志浩1(),崔彦斌2,许光文1,2,武荣成2()   

  1. 1.沈阳化工大学机械与动力工程学院,辽宁 沈阳 110142
    2.中国科学院过程工程研究所多相复杂系统国家重点实验室,北京 100190
  • 通讯作者: 金志浩,武荣成
  • 作者简介:陆鹏飞(1995—),男,硕士研究生,1767811479@qq.com
  • 基金资助:
    国家自然科学基金项目(U1908201)

Abstract:

Using tire semi-coke as carbon source and silicon sand as silicon source,silicon carbide(SiC) was prepared by carbothermal reduction method at 1520℃. XRD, SEM and FTIR spectrometer were used to characterize the SiC prepared under different raw material particle size conditions. The influence law of raw material particle size on the phase, morphology, particle size and reaction degree of the synthesized SiC was investigated. The results show that the size of the raw material has a very important influence on the degree of synthesis reaction and the phase composition, morphology and size of the product.Within a certain particle size range, with the decrease of silicon sand particle size, SiC crystal type becomes complete and SiC whisker decreases gradually, while the SiC particle size distribution does not change significantly.With the increase of semi-coke size of tire, the product phase gradually becomes single, and the proportion of SiC particle size and whisker decreases gradually. In addition, by measuring the C/Si ratio in the product and confirming the presence of the intermediate product SiO, it is inferred that the formation mechanism of SiC particles is gas-solid (VS) reaction, while the formation mechanism of SiC whiskers is gas-gas(VV) reaction.

Key words: tire carbocoal, SiC, particle size distribution, carbothermic reduction, generation mechanism

摘要:

以轮胎半焦为碳源,石英砂为硅源,在1520℃下通过碳热还原法制备了碳化硅。采用XRD、SEM和红外光谱仪等对不同原料粒度条件下制备的碳化硅进行了表征,探究了原料粒度对合成碳化硅物相、形貌、粒度和反应程度的影响规律。结果表明:原料粒度对碳化硅的合成反应进行程度及产物碳化硅的物相组成、形貌、粒度均有十分重要的影响。在一定粒度范围内,随着石英砂粒度的减小,碳化硅晶型变完整,且晶须逐渐减少,碳化硅的粒径分布没有明显变化;随着轮胎半焦粒度的增大,产物物相逐渐变为单一,碳化硅的粒径和晶须所占的比例逐渐减小。此外,通过对产物中C/Si 比的测定和存在中间产物SiO的证实,推测出了碳化硅颗粒的生成机理为气-固(VS)反应,而碳化硅晶须的生成机理为气-气(VV)反应。

关键词: 轮胎半焦, 碳化硅, 粒度分布, 碳热还原, 生成机理

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