Process and apparatus for making ultra-pure DMSO
US6414194B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 2000 |
| Grant date | Jul 2, 2002 |
| Priority date | — |
| Expiry date | Apr 24, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C315/06
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
One aspect of this invention relates to processes for solidifying dimethylsufoxide including the steps of partially solidifying a liquid phase including dimethylsulfoxide and one or more impurities, to form a mixture comprising solid dimethylsulfoxide and a liquid residue, and substantially separating the solid dimethylsulfoxide from the liquid residue, wherein the liquid residue comprises liquid dimethylsulfoxide and at least a portion of the impurities, and wherein the liquid residue is not subsequently treated by any step of partial solidification. In certain embodiments of the processes of the invention, ultra-high purity DMSO that exceeds the purity specifications for U.S.P. grade DMSO can be produced by employing solidification, fractional solidification and/or melt crystallization processes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.