TY - CONF AV - none SP - 298 TI - Determination of Excess Sodium Hydroxide in Geopolymer by Volumetric Analysis ID - scholars7411 KW - Caustic soda; Curing; Drying; Efflorescence; Fly ash; Geopolymers; Process engineering; Sodium; Surface chemistry; Volumetric analysis KW - Alkali metal concentration; Alkaline activators; Geopolymer; Geopolymerization; Hydrothermal curing; Leaching behaviours; Quantification methods; Sodium hydroxides KW - Inorganic polymers N2 - Efflorescence in geopolymers can be a significant issue as the binder contains much higher soluble alkali metal concentrations than conventional cements. This paper reports the quantification method used to evaluate efflorescence potential on fly ash based geopolymer from the leaching behaviour of alkali metal in the solution followed by volumetric analysis. In this study, NaOH was used as the only alkaline activator. Geopolymer synthesis at higher molarity of NaOH gives higher percentage of excess sodium hydroxide content in geopolymer, indicating the higher potential of efflorescenece. Meanwhile, the effect of hydrothermal curing condition at the same alkaline molarity results in the lowest percentage of 4.84 excess sodium hydroxide content in geopolymers compared to others. The systems were subjected to 65 relative humidity at 80°C for 5 days. An optimum Na2O content along with hydrothermal curing condition can results in optimization of geopolymerization reaction. © 2016 The Authors. N1 - cited By 11; Conference of 4th International Conference on Process Engineering and Advanced Materials, ICPEAM 2016 ; Conference Date: 15 August 2016 Through 17 August 2016; Conference Code:131138 PB - Elsevier Ltd SN - 18777058 Y1 - 2016/// EP - 301 VL - 148 A1 - Sani, N.A.M. A1 - Man, Z. A1 - Shamsuddin, R.M. A1 - Azizli, K.A. A1 - Shaari, K.Z.K. UR - https://www.scopus.com/inward/record.uri?eid=2-s2.0-85014015992&doi=10.1016%2fj.proeng.2016.06.621&partnerID=40&md5=8ce4dd5312a68344327fa68cf704ddcd ER -