Moving bed process for carbothermally synthesizing nonoxide ceramic
powders
    2.
    发明授权
    Moving bed process for carbothermally synthesizing nonoxide ceramic powders 失效
    碳热合成非氧化物陶瓷粉末的移动床工艺

    公开(公告)号:US5607297A

    公开(公告)日:1997-03-04

    申请号:US296051

    申请日:1994-08-24

    摘要: Carbothermally reduce a metal oxide to its corresponding metal nitride or metal carbide powder in a vertical gravity flow reactor by adding precursor pellets containing the metal oxide, a thermally decomposed binder material and carbon or a source of carbon directly to a heated reaction zone within the reactor. The pellets form a pellet bed, the top of which must be maintained within the heated reaction zone. The binder material is a blend of wheat and corn starches, optionally in conjunction with another binder such as melamine. The binder material thermally decomposes to a carbonaceous residue which functions both as an additional source of carbon and as a binder for the precursor pellets. The reactor may be modified by adding an internal vent line to remove volatile materials from the heated reaction zone before they have an opportunity to condense on internal reactor surfaces.

    摘要翻译: 通过将含有金属氧化物,热分解的粘合剂材料和碳或碳源的前体颗粒直接加入反应器内的加热反应区,将垂直重力流反应器中的金属氧化物碳氢化合物还原成其相应的金属氮化物或金属碳化物粉末 。 颗粒形成颗粒床,其顶部必须保持在加热的反应区内。 粘合剂材料是小麦和玉米淀粉的混合物,任选地与另一种粘合剂如三聚氰胺结合。 粘合剂材料热分解成碳素残渣,其既作为附加碳源又用作前体颗粒的粘合剂。 在反应器有机会在内部反应器表面冷凝之前,可以通过添加内部通风管线来从加热的反应区域中除去挥发性物质来改变反应器。

    Moving bed process for carbothermally synthesizing nonoxide ceramic
powders
    3.
    发明授权
    Moving bed process for carbothermally synthesizing nonoxide ceramic powders 失效
    碳热合成非氧化物陶瓷粉末的移动床工艺

    公开(公告)号:US5370854A

    公开(公告)日:1994-12-06

    申请号:US1990

    申请日:1993-01-08

    摘要: Carbothermally reduce a metal oxide to its corresponding metal nitride or metal carbide powder in a vertical gravity flow reactor by adding precursor pellets containing the metal oxide, a thermally decomposed binder material and carbon or a source of carbon directly to a heated reaction zone within the reactor. The pellets form a pellet bed, the top of which must be maintained within the heated reaction zone. The binder material is a blend of wheat and corn starches, optionally in conjunction with another binder such as melamine. The binder material thermally decomposes to a carbonaceous residue which functions both as an additional source of carbon and as a binder for the precursor pellets. The reactor may be modified by adding an internal vent line to remove volatile materials from the heated reaction zone before they have an opportunity to condense on internal reactor surfaces.

    摘要翻译: 通过将含有金属氧化物,热分解的粘合剂材料和碳或碳源的前体颗粒直接加入反应器内的加热反应区,将垂直重力流反应器中的金属氧化物碳氢化合物还原成其相应的金属氮化物或金属碳化物粉末 。 颗粒形成颗粒床,其顶部必须保持在加热的反应区内。 粘合剂材料是小麦和玉米淀粉的混合物,任选地与另一种粘合剂如三聚氰胺结合。 粘合剂材料热分解成碳素残渣,其既作为附加碳源又用作前体颗粒的粘合剂。 在反应器有机会在内部反应器表面冷凝之前,可以通过添加内部通风管线来从加热的反应区域中除去挥发性物质来改变反应器。