Materials Sciences and Applications, 2017, 8, 537-552 http://www.scirp.org/journal/msa ISSN Online: 2153-1188 ISSN Print: 2153-117X DOI: 10.4236/msa.2017.87037 July 5, 2017 Properties of Geopolymers Made from Fired Clay Bricks Wastes and Rice Husk Ash (RHA)-Sodium Hydroxide (NaOH) Activator Lynn Myllyam Beleuk à Moungam, Hawa Mohamed, Elie Kamseu, Ndigui Billong * , Uphie Chinje Melo Laboratory of Material Analysis, MIPROMALO, Yaoundé, Cameroon Abstract High cost has been pointed among factors that limit the promotion of geopo- lymers. To contribute to the reduction of the use of costly industrial sodium silicate in activators for geopolymers, a gel obtained with RHA and concen- trated sodium hydroxide was used in the present study to develop an alkaline activator with 8 M NaOH and to produce geopolymers with crushed fired clay bricks wastes (FCBW). Characteristics of the gel were compared to that of commercial sodium silicate which was also mixed with 8 M NaOH in the ratio 1:1 to produce geopolymers. Chemical and mineralogical analyses were done on raw materials. Fourier Transformed Infrared Spectroscopy (FTIR) was done on the gel, commercial sodium silicate and products. Biaxial four point flexural strength, bulk density, water absorption and scanning electron mi- croscopy (SEM) tests were also done on products. Results showed that RHA-NaOH alkaline activator has good potential in consolidating FCBW powder through geopolymerization process which gave products that had characteristics not far from that when the commercial sodium silicate was used. The gel obtained by mixing RHA and NaOH can contribute to the re- duction of the use of costly commercial sodium silicate in the production process of geopolymers. However, appropriate filtration process is needed for the RHA-NaOH gel to reduce its impurities as undissolved entities, which will consequently contribute to improve the flexural strength, the density and the microstructure of its products which were low compared to when commercial sodium silicate was used. Keywords Rice Husk Ash, Sodium Hydroxide, Fired Clay Bricks Waste, Geopolymer, Sustainability How to cite this paper: Beleuk à Moun- gam, L.M., Mohamed, H., Kamseu, E., Billong, N. and Melo, U.C. (2017) Proper- ties of Geopolymers Made from Fired Clay Bricks Wastes and Rice Husk Ash (RHA)- Sodium Hydroxide (NaOH) Activator. Ma- terials Sciences and Applications, 8, 537- 552. https://doi.org/10.4236/msa.2017.87037 Received: March 14, 2017 Accepted: July 2, 2017 Published: July 5, 2017 Copyright © 2017 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access