A novel green approach for making hybrid inorganic- organic geopolymeric cementitious material utilizing fly ash and rice husk. Issue 4 (December 2016)

• Record Type: Journal Article
• Authors: Amritphale, Sudhir S.; Mishra, Deepti; Mudgal, Manish; Chouhan, Ramesh K.; Chandra, Navin
• Is Part Of: Journal of environmental chemical engineering. Volume 4:Issue 4(2016:Dec.)Part A
• Page Start: 3856
• Page End: 3865
• Publication Date: 2016-12
• Subjects: Hybrid -- Inorganic organic -- Geopolymer -- Pentavalent silicon; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2016.08.015
• Languages: English
• ISSNs: 2213-2929

Abstract

Graphical abstract: Highlights: Novel process for preparation of hybrid inorganic −organic geopolymeric material. In −situ synthesis of sodium silicate thus obviating its need. Transformation of tetra coordinated silicon complexes in fly ash and rice husk to. Penta coordinated silicon complexes in hybrid inorganic −organic geopolymeric material. Abstract: A novel green process 1 has been presented in this paper for preparation of hybrid inorganic −organic geopolymeric cementitious material utilizing fly ash, and rice husk which helps in reduction of greenhouse gas (GHG) carbon dioxide thus addressing the issue of global warming. The process involves synergistic and simultaneous chemical reactions among glassy silico- aluminous phase present in fly ash and amorphous silica and organic molecules present in rice husk in presence of alkali. This results in in −situ synthesis of sodium silicate and transformation of tetra coordinated silicon complexes originally present in fly ash and rice husk to penta coordinated silicon complexes in hybrid inorganic −organic geopolymeric material. This has been confirmed by 29 Si NMR spectra of hybrid inorganic −organic geopolymeric material. The organic molecules present in rice husk resulting in development homogenous, non brittle hybrid inorganic −organic matrix. Hybrid inorganic −organic geopolymeric material possess 25% more flexural strength with a value of 2–4 MPa in comparison to conventional geeopolymeric material which possess flexural strength of 1–2 MPa only. The formation of hybrid inorganic −organic matrix is confirmed by presence of peaks of organic and inorganic phases in XRD. The presence of organic and inorganic linkages in FTIR spectra of hybrid inorganic organic geopolymeric material further confirms formation of hybrid matrix. The presence of characteristic 27 Al NMR signal of geopolymeric material at around 59 ppm in both conventional as well as in hybrid inorganic-organic geopolymeric material confirmed the formation of geopolymeric material in both the cases.