Tantalum-material multilevel distillation crucible and distillation process

A distillation process with a multilevel distillation crucible made of a tantalum material, wherein said process comprises the steps of

• providing said distillation crucible including:
• a crucible body, a heat-insulation plate and a receiving hood;
• said crucible body is made of tantalum with a shape of trumpet-like truncated cone having an inner or outer top diameter of 100-250 mm, an inner or outer bottom diameter of 300-500 mm, and a height of 250-400 mm, whereby said shape of the crucible body is facilitates blocking radiant heat and creates within said crucible body a temperature difference between the crucible body and the condensing zone;
• said heat-insulation plate is made of a refractory material with high-temperature resistance and geed heat-insulating properties;
• fitting said heat-insulation plate around an upper end of the crucible body, while the receiving hood covers a top of said crucible body and is above the heat-insulation plate;
• adjusting a temperature difference between a top of the heat-insulation plate and a bottom of the crucible body by alternating a number of the heat-insulation plates;
• placing rare earth metals to be distilled at the bottom of the crucible, and
• heating the crucible to distill the rare earth metals.

A distillation process with a multilevel distillation crucible made of a tantalum material, wherein said process comprises the steps of

• providing said distillation crucible including:
• a crucible body, a heat-insulation plate, and a receiving hood;
• said crucible body is made of tantalum with a shape of trumpet-like truncated cone having an inner or outer top diameter of 100-250 mm, an inner or outer bottom diameter of 300-500 mm, and a height of 250-400 mm, whereby said shape of the crucible body is facilitates blocking radiant heat and creates within said crucible body a temperature difference between the crucible body and the condensing zone;
• said heat-insulation plate is made of a refractory material with high-temperature resistance and heat-insulating properties;
• fitting said heat-insulation plate around an upper end of the crucible body, while the receiving hood covers a top of said crucible body and is above the heat-insulation plate;
• adjusting a depth of the crucible body inserted in a heat resource by adding or reducing a number of spacer sheets or pads at a bottom of the crucible body, thereby adjusting temperature difference between a top of the heat-insulation plate and the bottom of the crucible body;
• placing rare earth metals to be distilled at the bottom of the crucible, and
• heating the crucible to distill the rare earth metals.