Method for producing solar cell-grade silicon from rice hulls
US4214920A · kind A · utility
23Cited by
9References
31Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1979 |
| Grant date | Jul 29, 1980 |
| Priority date | — |
| Expiry date | Mar 23, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/253
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention relates to the production of high purity solar grade silicon from common rice hulls. A unique process for material purification and reduction includes leaching the rice hulls in acid followed by treatment with high purity water, coking the acid-cleaned hulls in a non-oxidizing ambient, compensating the carbon or silica content of the coked hulls to obtain a desired carbon to silica ratio and reducing the silica to produce high purity silicon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.