发明名称 |
Method and apparatus for acetylating cellulose |
摘要 |
In a production process of a cellulose acetate which comprises (a) a reduced pressure-acetylation step of acetylating a cellulose under a reduced pressure in the presence of sulfuric acid or other acidic catalyst, with distilling off a gaseous phase component of the reaction system out of the system, and (b) a post-acetylation step of allowing the acetylation to further proceed by increasing the pressure as compared with the pressure of the reduced pressure-acetylation step by means of release of the pressure reduction of the reaction system or the like, the shift operation from the reduced pressure-acetylation step to the post-acetylation step is conducted by taking a distilling rate of a distillate in the reduced pressure-acetylation step as an index to control the reaction temperature of the post-acetylation step. The shift operation from the reduced pressure-acetylation step to the post-acetylation step may also be conducted by taking a distilling rate after the distilling rate in the reduced pressure-acetylation step has reached a maximum value.
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申请公布号 |
US5869646(A) |
申请公布日期 |
1999.02.09 |
申请号 |
US19970787565 |
申请日期 |
1997.01.22 |
申请人 |
DAICEL CHEMICAL INDUSTRIES, LTD. |
发明人 |
YAMASHITA, MITSURU |
分类号 |
B01J19/00;C08B3/06;C08B17/02;(IPC1-7):C08B3/06 |
主分类号 |
B01J19/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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