title: Upgrading the rice husk char obtained by flash pyrolysis for the production of amorphous silica and high quality activated carbon.
abstract: The overall valorization of rice husk char obtained by flash pyrolysis in a conical spouted bed reactor (CSBR) has been studied in a two-step process. Thus, silica has been recovered in a first step and the remaining carbon material has been subjected to steam activation. The char samples used in this study have been obtained by continuous flash pyrolysis in a conical spouted bed reactor at 500°C. Extraction with Na2CO3 allows recovering 88% of the silica contained in the rice husk char. Activation of the silica-free rice husk char has been carried out in a fixed bed reactor at 800°C using steam as activating agent. The porous structure of the activated carbons produced includes a combination of micropores and mesopores, with a BET surface area of up to 1365m(2)g(-1) at the end of 15min.
authors.affiliation: Department of Chemical Engineering, University of the Basque Country UPV/EHU, P.O. Box 644, E48080 Bilbao, Spain.
authors.forename: Jon
authors.initials: J
authors.lastname: Alvarez
authors.affiliation: Department of Chemical Engineering, University of the Basque Country UPV/EHU, P.O. Box 644, E48080 Bilbao, Spain.
authors.forename: Gartzen
authors.initials: G
authors.lastname: Lopez
authors.affiliation: Department of Chemical Engineering, University of the Basque Country UPV/EHU, P.O. Box 644, E48080 Bilbao, Spain.
authors.forename: Maider
authors.initials: M
authors.lastname: Amutio
authors.affiliation: Department of Chemical Engineering, University of the Basque Country UPV/EHU, P.O. Box 644, E48080 Bilbao, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Bilbao
authors.affiliation: Department of Chemical Engineering, University of the Basque Country UPV/EHU, P.O. Box 644, E48080 Bilbao, Spain. Electronic address: martin.olazar@ehu.es.es.
authors.forename: Martin
authors.initials: M
authors.lastname: Olazar
mesh_terms: D002254:Carbonates / Q000302:isolation & purification; D002606:Charcoal / Q000138:chemical synthesis*; D006358:Hot Temperature; D008855:Microscopy, Electron, Scanning; D012275:Oryza / Q000737:chemistry*; D016062:Porosity; D012822:Silicon Dioxide / Q000138:chemical synthesis*; D013052:Spectrometry, X-Ray Emission; D013227:Steam
chemical_list: D002254:Carbonates; D013227:Steam; D002606:Charcoal; C005686:sodium carbonate; D012822:Silicon Dioxide
keywords: Activated carbon; Adsorbent; Char; Rice husks; Steam activation