Geopolymerisation of fly ashes with waste aluminium anodising etching solutions

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:181

Article

Ogundiran, M. B.¹  Nugteren, H. W.¹  Witkamp, G. J.² 

[1] Delft Univ Technol, Dept Chem Engn, Prod & Proc Engn Grp, Julianalaan 136, NL-2628 BL Delft, Netherlands

[2] Delft Univ Technol, Dept Biotechnol, Environm Biotechnol Grp, Julianalaan 67, NL-2628 BC Delft, Netherlands

关键词: Recycling;    Geopolymer;    Waste aluminium etching solution;    Fly ash;    Elemental leaching;   

DOI  :  10.1016/j.jenvman.2016.06.017

来源: Elsevier

【 摘 要 】

Combined management of coal combustion fly ash and waste aluminium anodising etching solutions using geopolymerisation presents economic and environmental benefits. The possibility of using waste aluminium anodising etching solution (AES) as activator to produce fly ash geopolymers in place of the commonly used silicate solutions was explored in this study. Geopolymerisation capacities of five European fly ashes with AES and the leaching of elements from their corresponding geopolymers were studied. Conventional commercial potassium silicate activator-based geopolymers were used as a reference. The geopolymers produced were subjected to physical, mechanical and leaching tests. The leaching of elements was tested on 28 days cured and crushed geopolymers using NEN 12457-4, NEN 7375, SPLP and TCLP leaching tests. After 28 days ambient curing, the geopolymers based on the etching solution activator showed compressive strength values between 51 and 84 MPa, whereas the commercial potassium silicate based geopolymers gave compressive strength values between 89 and 115 MPa. Based on the regulatory limits currently associated with the used leaching tests, all except one of the produced geopolymers (with above threshold leaching of As and Se) passed the recommended limits. The AES-geopolymer geopolymers demonstrated excellent compressive strength, although less than geopolymers made from commercial activator. Additionally, they demonstrated low element leaching potentials and therefore can be suitable for use in construction works. (C) 2016 Published by Elsevier Ltd.

【 授权许可】

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