Synthesis of porous alkali-activated materials for high-acidic wastewater treatment. (February 2020)

• Record Type: Journal Article
• Authors: Chindaprasirt, Prinya; Rattanasak, Ubolluk
• Is Part Of: Journal of water process engineering. Volume 33(2020)
• Publication Date: 2020-02
• Subjects: Fly ash -- Bottom ash -- Porous alkali-activated materials -- Acidic wastewater; Water-supply engineering -- Periodicals; Saline water conversion -- Periodicals; Seawater -- Distillation -- Periodicals; Sanitary engineering -- Periodicals; Sewage -- Purification -- Periodicals; 627
• DOI: 10.1016/j.jwpe.2019.101118
• Languages: English
• ISSNs: 2214-7144

Abstract

Graphical abstract: Highlights: New self-releasing alkali materials in the form of porous AAMs are fabricated from fly ash and bottom ash. The monitoring of these new materials in acidic wastewater has been reported. The porous AAMs are suitable for acidic wastewater treatment. The treatment process was cost-effective requiring only a small amount of alkali solution. Abstract: Many industries and industrial processes, such as electroplating, acid mine drainage, the pharmaceutical industry, and industries that use phosphorous, produce large volumes of acidic wastewater that must be treated before discharge. Generally, a large quantity of an alkali, such as lime, caustic soda, or soda ash is used to neutralize the acidic wastewater and it is a costly treatment process. Therefore, new self-releasing alkali materials were studied. This research proposed the synthesis of sustainable porous alkali-activated materials (porous AAMs) by a simple method for acidic wastewater treatment. Industrial wastes, i.e., fly ash and bottom ash from a power plant, were employed to produce porous AAMs using sodium silicate solution as a foaming agent. The test results showed that fly ash and bottom ash AAMs had the potential to be used as pH modifiers. 0.001 M HCl solution (pH of 3) was selected as the representative acidic wastewater, and the pH of the solution fell to within the allowable discharge pH range of 5.5–9.0 according to the effluent discharge standard of Thailand. The retention time was three days for a solid-to-solution ratio of 1:500 w/v (g/ml). Porous AAMs present an attractive way of utilizing waste coal ashes compared to a cost-effective method for acidic wastewater treatment.