Method for crystallizing (meth)acrylic acid and method for regulating content of polymerization inhibitor in product (meth)acrylic acid
US8704000B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 2010 |
| Grant date | Apr 22, 2014 |
| Priority date | — |
| Expiry date | May 27, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/43
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
PROBLEMThere is provided a melting method of (meth)acrylic acid crystal which is capable of providing a higher quality of (meth)acrylic acid without carrying out an additional purification treatment to (meth)acrylic acid obtained by a crystallization operation accompanied by melting of (meth)acrylic acid. In addition, there is provided a simple method for adjusting a content of polymerization inhibitor in a product (meth)acrylic acid.SOLUTIONIn the crystallization method melting (meth)acrylic acid crystal while wetting with the crystalline molten liquid, a polymerization inhibitor is added to a molten liquid melted after initiation of melting, and all of crystal is melted while circulating and feeding the molten liquid containing said polymerization inhibitor to the crystal. In addition, a content of polymerization inhibitor in product (meth)acrylic acid is adjusted by adding a predetermined amount of polymerization inhibitor corresponding to a product specification to the molten liquid melted after initiation of melting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.