Optimization of Parameters and Methodology for the Synthesis of LTA-Type Zeolite Using Light Coal Ash

Abstract

The synthesis of zeolites using waste as a source of Si and Al is well known, and light coal ash has been studied to minimize the problems of waste management and mitigate environmental effects. The residue used in this work was supplied by Coal Workers Assistance Society (SATC) Criciúma–SC/Brazil, and had 24.09% Al2O3 and 54.25% SiO2 in its chemical composition. Synthesis studies using this residue with the objective of obtaining LTA zeolites were carried out by hydrothermal means, alkaline fusion, and the combination of the two methods, varying parameters such as crystallization time, Na/T ratio, OH/ratio, ultrasound exposure, gel agitation temperature, and the alkaline melting temperature of the residue. The results were characterized by X-ray diffraction (XRD) techniques and scanning electron microscopy (SEM-FEG). It was possible to obtain 70% crystalline zeolite type LTA for the first time at mild conditions with temperatures below 200 °C by alkaline fusion with smaller amounts of NaOH and short times (2 h). Thus, suitable parameters were determined for future scaling.

Renewable Diesel Production from Palm Fatty Acids Distillate (PFAD) via Deoxygenation Reactions

“…The XRD pattern after calcination showed only the quartz signal, indicating the destruction of the crystalline structure [26,27]. After zeolite synthesis and calcination, diffraction peaks attributed to zeolite A (ICOD 01-089-5421) and sodalite (COD 96-900-3327) were observed [27][28][29]. X-ray diffraction patterns of catalysts are shown in Figure 2.…”

Ambient-Pressure Synthesis of Highly Crystallized Zeolite NaA

“…Particularly, the Linde-A (LTA) zeolite has most widely been used due to its high cation exchange capacity concomitant with its high Al content. , The easy ion exchangeable nature of Na with Ca and K provides the NaA zeolite with diversity in pore opening and has hence made NaA the most synthesized zeolite worldwide. , The largest industrial application of zeolite LTA is in the detergent builder and water softener composition. , Cruz et al used coal fly ash as a source of Si and Al with NaOH for the synthesis of the LTA zeolite and managed to produce a 70% crystalline zeolite type through the alkaline fusion treatment followed by the HT process …”

“…32 for the synthesis of the LTA zeolite and managed to produce a 70% crystalline zeolite type through the alkaline fusion treatment followed by the HT process. 34 Herein, we introduce a facile ambient-pressure synthesis (APS) of zeolite NaA crystals. In this tactic, the reaction occurs at ambient pressure and 120 °C temperature in a glass tube as an oil sealant is used in the place of the Teflon reactor to create a physical barrier between the raw material content and the surroundings.…”

Aluminium Tertiary Industry Waste and Ashes Samples for Development of Zeolitic Material Synthesis

“…Among the various types of zeolite, zeolite like A-type is one of the most important molecular sieves, because presents high adsorption capacity and can easily exchange sodium ion with other cations, especially calcium. Furthermore, zeolite A is the most commercialized in the world, mainly used as an additive in laundry detergents [10,11].…”