Influence of Foaming Agent/Water Ratio and Foam/Geopolymer Paste Ratio to the Properties of Fly Ash-based Lightweight Geopolymer for Brick Application

Abstract

Nowadays, the demand for lightweight building materials has been growing worldwide. This paper presents an investigation on the use of waste materials of fly ash as a source materials for the production of lightweight geopolymer by using foaming agents. The key properties for the foamed geopolymer namely density, compressive strength, and water absorption were investigated. The chemical composition of materials and morphology analysis were studied to find the microstructure properties of foamed geopolymer. The foamed geopolymer were prepared by combination of 12 M Sodium Hydroxide (NaOH) solution and Sodium Silicate (Na 2 SiO 3 ) solution. The ratio of Na 2 SiO 3 /NaOH and ratio of fly ash/alkaline activator were kept constant at 2.5 and 2.0, by mass respectively. The effect of different ratio of foaming agent/water and foam/geopolymer paste were investigated at 7 days of ageing and cured at 80°C for 24 hours. In general, the results showed that the fly ash-based lightweight geopolymer has good potential as brick application.Keywords: lightweight brick, geopolymer, foaming agent/water ratio, foam/geopolymer paste ratio Brick is one of the most important building material in construction industry. Manufacturing of conventional brick are generally uses of clay with high temperature kiln firing or from ordinary Portland cement (OPC) concrete [1]. The high temperature kiln firing (900 -1000°C) not only consumes significant amount of energy, but also releases substantial quantity of greenhouse gases [2]. Production of OPC concrete bricks also consumes large amount of energy and releases substantial quantity of CO 2 . This is because the production of 1 kg of OPC consumes approximately 1.5 kWh of energy and releases about 1 kg of CO 2 to the atmosphere [3]. Due to this problem, the utilization of waste materials has been studied by several researchers focused on the environmental protection and sustainable development [4][5][6]. The uses of fly ash, which is a waste produced from the thermal power plant can be used as a cement and clay replacement in making bricks through geopolymerization process.Geopolymerization occurs through the reaction between aluminosilicate source materials with highly alkaline solutions. The alkaline activator solution are usually come from the combination of sodium hydroxide and sodium silicate or a potassium hydroxide and potassium silicate solution [7]. Most waste materials such as fly ash, blast furnace slag and mine tailings contain sufficient amounts of reactive alumina and silica can be used as source materials for geopolymerisation reactions [8]. Among the above mentioned waste materials, fly ash get most consideration to be a source materials in manufacturing of geopolymer due to their genially structure and size, also *

A review on the porous geopolymer preparation for structural and functional materials applications

“…Density‐compressive strength for building insulation produced using different preparation method 15,16,56,62,63,66,68,70,85,91,97,112–114,125,126,128,129,137,139,141,143,144,156–158,169,178,181–187,191–194 …”

“…F I G U R E 6 Density-compressive strength for building insulation produced using different preparation method 15,16,56,62,63,66,68,70,85,91,97,[112][113][114]125,126,128,129,137,139,141,143,144,[156][157][158]169,178,[181][182][183][184][185][186][187][191][192][193][194] to the atmosphere to prepare a geopolymer-based pervious concrete. The relationships between the densityvoid content, compressive strength-density, and compressive strength-void content were formulated and similar to those of the conventional pervious concrete, and could be used for fabricating pervious concrete with geopolymer binder.…”

Preparation of Fly Ash-Ladle Furnace Slag Blended Geopolymer Foam via Pre-Foaming Method with Polyoxyethylene Alkyether Sulphate Incorporation

“…PAS is a brown liquid extracted from coconut oil, and it can be easily and quickly dissolved in water to generate foam [4]. Based on previous studies, Ibrahim et al [5] produced fly ash geopolymer foam with PAS foam-to-paste ratios ranging from 0.5 to 2.0, revealing that the compressive strength of the foamed geopolymer (17.8-4.1 MPa) decreased with increasing foam-to-paste ratio. Mastura et al [6] and Ibrahim et al [4] produced fly ash geopolymer foam with a PAS foam-to-paste ratio of 1.0, reporting that the compressive strength of the foamed geopolymer was in the range of 9.0 MPa to 19.3 MPa.…”

Effect of Aluminium Powder on Kaolin-Based Geopolymer Characteristic and Removal of Cu2+

“…The addition of foaming agent also affects the properties of the geopolymer such as its chemical composition, porosity, morphology, phase and functional group [ 38 ]. Some attempts have been made to produce geopolymer using different types of foaming agent such as metal powder (aluminium powder), hydrogen peroxide (H 2 O 2 ), and sodium hypochlorite [ 39 , 40 , 41 ]. Amorphization by mechanical alloying also can improve the porosity of the geopolymer adsorbent [ 42 ].…”