The present work demonstrates that carbonaceous template preforms derived from jute stem by thermal and microwave processing can be infiltrated at room temperature under vacuum with silica sol, obtained by acid catalyzed hydrolysis of tetra ethyl orthosilicate (TEOS). The microwave processed carbon-preforms are better suited for exercising control of SiO2 infiltration. The oven-dried hybrid C/SiO2 material accumulates silica as SiO 2·nH2O (n lying approximately between 1 and 3) and may be suitably converted, depending on the modes of processing, into macroporous cellular SiO2 or SiC ceramics or SiC/SiO2/C or SiC/C or SiC/SiO2 composites with tailored composition and microstructures. The processes for synthesis of the specific products have been developed and their phase compositions and microstructures have been examined through characterization by bulk density measurements, X-ray diffraction and scanning electron microscopy. © 2010 Elsevier Ltd and Techna Group S.r.l. All rights reserved.