Physicochemical and Engineering Properties of Coal Bottom and Fly Ash Mixtures Modified with Poly-Vinyl Alcohol and Sodium Lauryl Sulfate

• Published in: Lecture Notes in Civil Engineering
• Main Author: Ayob A.; Robert C.G.; Mokhtar H.; Rahim M.A.; Harnaeni S.R.; Bahatin M.; Rahman F.A.; Shakrani S.A.; Ali D.S.H.
• Format: Conference paper
• Language: English
• Published: Springer Science and Business Media Deutschland GmbH 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85181980885&doi=10.1007%2f978-981-99-6026-2_2&partnerID=40&md5=1c9efea64d53fe270c98567d02f8d8bf

Re-using bottom ash (BA) and fly ash (FA) can decrease disposal volumes and cost while also reducing dependence on non-renewable resources for sustainable aims in geotechnical applications. This study investigated the modification of the physicochemical and engineering properties of coal bottom and fly ash (BFA) with poly-vinyl alcohol (PVA) and sodium lauryl sulfate (SLS) at concentrations ranging from 1.5 to 2.5%. The different mixture ratios were denoted as BA100, BA60 FA40, BA40 FA60, and FA100. The proportion of BA40 FA60 modified with SLS at a concentration of 2.5% yielded a mildly alkaline pH with a distinct surface morphology consisting of well-distributed, smooth, and fine particles. The modification by using PVA and SLS generated high maximum dry density, high optimum moisture content, and improved unconfined compressive strength values ranging from 8.36 to 22.14% as compared to unmodified specimens after a 28-day curing period. These results were attributed to PVA/SLS–coal ash electrostatic physical bonding. Lower permeabilities over time of similar mixtures were recorded, ranging from 5.22 × 10–4 to 5.29 × 10–4 cm s−1 in SLS solution concentrations ranging from 1.5 to 2.5%. These coal ash wastes showed no unique changes in terms of the variation of main oxide content and crystalline phase for alteration concentrations for both modifiers’ solutions. These findings indicate that the physicochemical and engineering properties can be strengthened via a modification process achieved by inducing the novel stability of electrostatic suspension. In turn, this can actively interact with other matrices, such as those intended for soil as well as polymer or composite materials. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2024.