SiO2 Promoted CaO Diffusion to C Phase at 1500 and 1700 °C

Energies

Lijuan Ni¹  Yue Pan¹  Zhenyu Liu¹  Renxing Wang²  Qingya Liu²  Junfei Wu² 

[1] Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China;State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China;

关键词: calcium carbide;    diffusion;    Kirkendall effect;    CaO;    Carbon;    SiO₂;   

DOI  :  10.3390/en14030587

来源: DOAJ

【 摘 要 】

To better understand the mass transfer behaviors in CaC₂ production from CaO and coke, this paper studies the diffusion behaviors of CaO and graphite, with or without ash, at 1500 and 1700 °C. CaO and graphite are pressed into tablets and heated alone or in close contact. Physical and chemical changes in these tablets are analyzed by XRD and SEM+EDX. In some experiments, thin Mo wires are placed between the closely contacted CaO and graphite tablets to identify the diffusion direction. It is found that the diffusion between CaO and low-ash graphite is very limited. SiO₂ in a high-ash graphite diffuses into CaO tablet and reacts with CaO to form Ca₂SiO₄, which then diffuses into the graphite tablet easily and leads to CaC₂ formation at 1700 °C.

【 授权许可】

Unknown