Patent ID: 11884632
Assignee: ZHEJIANG HENGYI PETROCHEMICAL RESEARCH INSTITUTE CO., LTD.
Field: Chemical engineering (Chemistry)
Classification: CPC C  B  Y | IPC B  C

Claim 11:
12. The method of claim 8, wherein
the conditions of the two-stage crystallization with an ethanol-hydrothermal system under variable temperatures comprise: crystallizing at 50-80° C. for 1-1.5 days, and crystallizing at 100-120° C. for 1.5-2 days; and/or
the roasting conditions comprise: the temperature is within a range of 200-600° C., and the time is within a range of 1-20h; and/or
the contacting conditions comprise: the temperature is within a range of 50-120° C., the pressure is within a range of 0.5-10 kg/cm2, the time is within a range of 0.1-5h.