Method of producing fluorinated carbon from rice husk
AssigneeKing Fahd University of Petroleum and Minerals
InventorsChanbasha Basheer, Isam H. Aljundi, Rashed Saed Bakdash
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Abstract
A method for producing a fluorinated carbon adsorbent which involves digesting rice husk, sulfonating the digested rice husk, and fluorinating the sulfonated rice husk. The method yields a fluorinated carbon adsorbent material having an adsorption capacity for CO2 of 1.6 to 2.5 mmol/g, an adsorption capacity for CH4 of 0.4 to 0.8 mmol/g, and an adsorption capacity for N2 of 0.1 to 0.4 mmol/g, at a temperature of 273 to 298 K and a pressure of 0.75 to 1.5 atm. Also disclosed is a method for separating a mixture of gases using the fluorinated carbon adsorbent.
Claims20
A method of making a fluorinated carbon adsorbent, the method comprising:
- microwave irradiating a mixture of rice husk and aqueous sulfuric acid to a temperature of 100 to 300° C. to form a digested rice husk;
- drying and milling the digested rice husk to form a powdered rice husk;
- microwave irradiating the powdered rice husk in the presence of fuming sulfuric acid to form a sulfonated rice husk;
- and
- microwave irradiating the sulfonated rice husk in the presence of hydrofluoric acid (HF) to a temperature of 50 to 150° C. thereby forming the fluorinated carbon adsorbent;
- wherein the fluorinated carbon adsorbent has a carbon content of 60 to 75 wt %, an oxygen content of 14 to 34.5 wt %, a fluorine content of 5 to 9 wt %, a sulfur content of 0.5 to 2 wt %, and a silicon content of less than 0.5 wt %, each relative to a total weight of the fluorinated carbon adsorbent.
A fluorinated carbon adsorbent obtained by fluorinating a sulfonated rice husk, wherein the fluorinated carbon adsorbent has a surface area of 500 to 600 m2/g, a pore volume of 0.1 to 0.3 cm3/g, and a mean pore radius of 0.5 to 0.75 nm.
Dependencies are inferred from the claim text.