FIELD: technological processes.
SUBSTANCE: invention relates to processing agricultural wastes, particularly rice husks. Screened and washed husks are treated with 10-30% sodium hydroxide solution at 90-130°C for 30-120 minutes. Cellulose containing 2-8% silicon dioxide is obtained. The obtained alkaline solution of organic substances is treated with hydrochloric acid solution while separating lignin containing 6-15% silicon dioxide. The solution remaining after separating lignin is treated with ammonia liquor while depositing amorphous silicon dioxide containing 5-22% and 0.04-0.6% carbon after drying and calcination, respectively. Overall wastes make up 6-30% of the weight of the initial husks.
EFFECT: ensuring more complete use of rice husks to obtain cellulose, lignin and amorphous silicon dioxide and reducing the temperature for obtaining amorphous silicon dioxide.
8 cl, 2 tbl, 31 ex
| Title | Year | Author | Number |
|---|---|---|---|
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