rice being the most harvested crop we are left with agricultural waste such as
Rice husk in vast quantities .https://en.wikipedia.org/wiki/Rice_hulls with in it 20% of its dry mass is SiO2. after full burn it's concentrated up to 95% by mass of the ash
which is pure white but left over carbon can make black or grey . it can be use to make insulation material up to 1300C as it is, and just mixing with
slacked lime(Ca(OH)2) can make Calcium-silicate bricks and sheets for refractory. if you heat Rice hulls in a microwave with proper insulation (1500C)
can make SiC micro particles. the ash can be used to make Na2SiO3 with ease. rice hull charcoal can be used in the production of elemental phosphorus.TriiodideFrog - 12-1-2021 at 04:53
Interesting. Could you further explain on the phosphorus part?rockyit98 - 12-1-2021 at 05:19
Interesting. Could you further explain on the phosphorus part?
4 Ca5(PO4)3F + 18 SiO2 + 30 C → 3 P4 + 30 CO + 18 CaSiO3 + 2 CaF2
SiO2 and C are from R.H.A and rice hull charcoal.njl - 12-1-2021 at 07:14
If rice husks are 20 percent silica by dry mass, how can they be turned into effective charcoal? Isn't the purpose of charcoal to get relatively pure
carbon?rockyit98 - 12-1-2021 at 11:37
If rice husks are 20 percent silica by dry mass, how can they be turned into effective charcoal? Isn't the purpose of charcoal to get relatively pure
carbon?
it's depend on the use case , if you need to make SiC having SiO2 is an advantage because its fine and well mixed .half of work done for you. fusso - 13-1-2021 at 11:23
How does SiO2 get into the rice husk in the first place? As soluble silicate salts?RustyShackleford - 13-1-2021 at 11:45
How does SiO2 get into the rice husk in the first place? As soluble silicate salts?
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nobody knows for sure (at least I think). further research is needed.EthidiumBromide - 15-1-2021 at 05:19
It has been partially elucidated, rice in particular has an aquaporin-type membrane protein of the NIP2 family, primarily expressed in roots, which is
responsible for uptake of Si in the form of Si(OH)4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2048782/pdf/pp1...
Two U-M researchers turn useless waste from rice processing into the high-purity silica compounds that are used in everything from toothpaste to
tires. The technique could eliminate millions of tons of CO2 emissions every year, and it’s 90 percent less expensive than the
current method
