Synthesis of Zeolites Materials Using Fly Ash and Oil Shale Ash and Their Applications in Removing Heavy Metals from Aqueous Solutions

Abstract

Fly ash and oil shale ash generated from power plants can be transformed to suitable materials usable for removal of heavy metals. Due to their high silica content, fly ash and oil shale ash have been considered as the main stone of zeolite synthesis. In this work, we synthesized zeolites from class F fly ash (FA) and modified oil shale ash (MOSA) by alkaline fusion followed by refluxing. Our synthesis process focused on the effect of quantity of NaOH on the crystallinity of the reaction products: Na-P1 and Na-P2 type zeolites synthesized, respectively, from FA and MOSA. e effect of NaOH mass (1, 2, 4, and 8 g) was investigated with the following synthesis conditions: 2 h fusion at 650°C, 2 h agitation, and refluxing for 12 hours. e experimental results demonstrated that the crystallinity of Na-p1 and Na-P2 zeolites increased with increasing the mass of NaOH. e resulting products were characterized with X-ray diffraction, FTIR, and scanning electron microscopy. e reaction products ZV4 and ZM4 synthesized, respectively, from FA and MOSA and containing main zeolite phases with a crystallinity of 92.7% of Na-P1 and 83.6% of Na-P2, respectively, were chosen as adsorbents for the adsorption experiments. Series of experiments were carried out to study the removal of lead, zinc, and chromium by ZV4 and ZM4. e results allowed us to know the optimal conditions of adsorption for the three heavy metals. Adsorption data have been interpreted in terms of Langmuir and Freundlich isotherms. e results showed that lead has a higher affinity for ZM4 than ZV4 and zinc has similar adsorption efficiency for both sorbents that was remarkably reduced for chromium. e results of the present work suggest that zeolites synthesized from MOSA may be considered as effective as those synthesized from FA for heavy metals adsorption.

Treated oil shale ash and its capacity to remove Cd and Pb from aqueous solutions

“…The studied oil shale sample was subjected to XRD analysis, similar results for Ellajjun oil shale have been earlier obtained by Hamadi et al [30]. In addition, in the current work, the XRD spectra of activated semi-cokes were measured as shown in Figure 1.…”

Portable SA/CMC entrapped bimetallic magnetic fly ash zeolite spheres for heavy metals contaminated industrial effluents treatment via batch and column studies

“…Therefore, promoting effective waste recycling methods that help produce high-value-added goods is essential. The synthesis of zeolites from CFA is a viable method for waste reuse 13 . Furthermore, CFA is a source of silicon and aluminium, and its cost-effectiveness has sparked interest in zeolite synthesis 14 .…”

“…Furthermore, zeolite has demonstrated a high selectivity for different heavy metal ions 13 , 15 . However, the use of pristine zeolite in practical applications is disadvantageous because it exhibits poor removal capability for certain heavy metals.…”

Hydrothermal Synthesis and Characterization of Zeolite A from Corn (Zea Mays) Stover Ash

“…Naturally occurring silicas found in agricultural waste are a good substitute for commercial silica precursors. Thus, raw materials from agricultural waste, such as corncob-stalk-and-leaves ash [ 12 ], rice husk ash [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ], sugar cane bagasse ash [ 25 , 26 ], barley ash [ 27 ], coal ashes [ 28 , 29 , 30 , 31 , 32 , 33 , 34 ], clay minerals [ 35 , 36 , 37 , 38 , 39 , 40 ], industrial slags [ 41 ], natural zeolites [ 42 ], and solid waste incineration ashes [ 43 , 44 , 45 ], are used as alternative and cheap source materials for the synthesis of zeolite. The use of agricultural waste materials, such as those in the field of water purification and in the removal of ammonium or heavy metals, makes them appealing as useful products that contribute to the mitigation of environmental problems.…”