Synthesis of Zeolite A from Mongolian Coal Fly Ash by Hydrothermal Treatment

2018 ◽  
Vol 271 ◽  
pp. 1-8 ◽  
Author(s):  
Ulambayar Rentsenorov ◽  
Batmunkh Davaabal ◽  
Jadambaa Temuujin

Raw coal fly ash and acid pretreated fly ash were used to synthesize A-type zeolite by hydrothermal treatment. In order to synthesize zeolite A an aqueous gel having a molar batch composition of Na2O:Al2O3:1.926SiO2:128H2O was utilized. Fly ash and zeolitic products were characterized by SEM, XRF, XRD and cation exchange capacity (CEC). After hydrothermal treatment, several types of zeolites were formed: zeolite A, analcime, faujasite and hydroxy-sodalite. The highest content of zeolite A was formed in the mixture treated at 80°C for 8 hours. CEC values of the zeolitic products were 28-38 times higher than that of in raw fly ash. Acid pretreatment which leads to low calcium and iron content is preferable method for processing of fly ash for the zeolite synthesis. Synthesized zeolite can be used for ion exchangers for water treatment.

2021 ◽  
Vol 2 (1) ◽  
pp. 53-59
Author(s):  
A. Korpa ◽  
V. Teneqja ◽  
S. Gjyli ◽  
A. Andoni

This paper summarizes the investigation results on the main parameters affecting the synthesis of type X and A zeolites using coal silicious fly ash (FA) as raw material. The synthesis was performed by dissolution of alkali-fused alumino-silicates, followed by hydrothermal treatment. The experimental data confirm that fly ash SiO2/Al2O3 ratio, NaOH/FA ratio, acid treatment of pre-fused fly ash, salinity of solution have a significant effect on type and properties of newly formed zeolites. In summary, the results show that A and X-type zeolite form with FA SiO2/Al2O3 ratio < 1.12 and > 1.86, respectively. Moreover, FA characterized by SiO2/Al2O3 mole ratio of 3.15 is suitable for X-type zeolite synthesis while A-type zeolite does not form without NaAlO2 addition. The crystallization occurs faster at higher temperatures although above 90°C X-type zeolite evolves into more stable phases whereas increasing the crystallization time from 1 to 72 hours, the yield of the synthetic products enhances from 60 to 75%. The use of seawater is responsible for the synthesis of X-type showing both lower purity and specific surface area. However, the synthetic products are characterized by high exchange capacity (> 320 meq/100 g), thus suggesting their successful application as adsorbents and catalysts in different types of wastewater and industrial waste treatments.


Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2375
Author(s):  
Yuhei Kobayashi ◽  
Fumihiko Ogata ◽  
Chalermpong Saenjum ◽  
Takehiro Nakamura ◽  
Naohito Kawasaki

In this study, a novel zeolite (K-type zeolite) was synthesized from coal fly ash (FA), and adsorption capacity on Pb2+ was assessed. Six types of zeolite (FA1, FA3, FA6, FA12, FA24, and FA48) were prepared, and their physicochemical properties, such as surface functional groups, cation exchange capacity, pHpzc, specific surface area, and pore volume, were evaluated. The quantity of Pb2+ adsorbed by the prepared zeolites followed the order FA < FA1 < FA3 < FA6 < FA12 < FA24 < FA48. Current results indicate that the level of Pb2+ adsorbed was strongly related to the surface characteristics of the adsorbent. Additionally, the correlation coefficient between the amounts of Pb2+ adsorbed and K+ released from FA48 was 0.958. Thus, ion exchange with K+ in the interlayer of FA48 is critical for the removal of Pb2+ from aqueous media. The new binding energies of Pb(4f) at 135 and 140 eV were detected after adsorption. Moreover, FA48 showed selectivity for Pb2+ adsorption in binary solution systems containing cations. The results revealed that FA48 could be useful for removing Pb2+ from aqueous media.


2018 ◽  
Vol 29 (3) ◽  
pp. 450-456 ◽  
Author(s):  
Tomonori Fukasawa ◽  
Akira Horigome ◽  
Achmad Dwitama Karisma ◽  
Norio Maeda ◽  
An-Ni Huang ◽  
...  

2003 ◽  
Vol 68 (6) ◽  
pp. 471-478 ◽  
Author(s):  
Dusica Vucinic ◽  
Igor Miljanovic ◽  
Aleksandra Rosic ◽  
Predrag Lazic

Coal fly ash was modified to zeolitic materials by hydrothermal treatment at 90 ?C. The zeolite synthesis was studied as a function of the mole ratio of Na2O/SiO2 in the reaction mixtures. The results showed that NaP1 zeolite is obtained when the Na2O/SiO2 mole ratio was 0.7. Hydroxysodalite is the dominant zeolite phase in modified fly ash treated with a higher Na2O concentration solution (Na2O/SiO2 = 1.3). The IR and XRD methods were used to determine the phases present in the starting sample and in the zeolitic materials.


2016 ◽  
Vol 1 (3) ◽  
pp. 145
Author(s):  
Jumaeri Jumaeri ◽  
Juari Santosa ◽  
Sutarno Sutarno ◽  
Ella Kusumastuti

Adsorption of Cr(III) and Cr(VI) in aqueous solution by the zeolite A from coal fly ash modified hexadecyltrimethylammonium bromide (HDTMAB) at various pH conditions has been carried out. Zeolite A was synthesized from fly ash through modified alkaline fusion hydrothermal process in a reactor stainless steel. The surface modification was performed using cationic surfactant HDTMAB twice as much as the cationic exchange capacity of the elite A resulted. The surfactant modified zeolite A was then applied to adsorption the metal ion chromium as Cr(III) and Cr(VI) in aqueous solution. The results showed that the  acidity (pH)  of adsorption conditions, affect the ability of adsorption surfactant modified zeolite A (SMZA) to Cr(III) and Cr(VI) in aqueous solution. The optimum pH conditions for the adsorption of Cr(III) and Cr(VI) on SMZA exist at pH 6. Surfactant modified zeolite A capable to adsorb either cation Cr(III) or anion Cr(VI).  Adsorption of SMZA on Cr(III) increased from 36.30% to 97.04% with the increase the acidity of pH of 2 to 6. Adsorption SMZA to Cr(VI) is lower than the adsorption of the Cr<sup>3+</sup>, adsorption increasing from 19.63 to 64.07% with increase pH of 2 to 6


2002 ◽  
Vol 28 (2) ◽  
pp. 155-160 ◽  
Author(s):  
Kunihiro Fukui ◽  
Motoki Kinugawa ◽  
Takashi Nishimoto ◽  
Hideto Yoshida

Fuel ◽  
2007 ◽  
Vol 86 (12-13) ◽  
pp. 1811-1821 ◽  
Author(s):  
Roberto Juan ◽  
Susana Hernández ◽  
José Manuel Andrés ◽  
Carmen Ruiz

2018 ◽  
Vol 19 (2) ◽  
pp. 105
Author(s):  
Novita Andarini ◽  
Tanti Haryati ◽  
Zuhrotul Lutfia

Fly ash containing 30-36% silica and 14,52-23,78% alumina can be potentially as raw material for synthetic zeolite such as zeolite A. Zeolite A is an aluminosilicate mineral which is rich in alumina so that this zeolite has a good cation exchange capability. Zeolite A has been synthesized by hydrothermal treatment after NaOH fusion. Fly ash has been fused with NaOH at 550 0C for 40 minutes and hydrothermally treated at 1000C for 5 hours. The hydrothermal treatment was conducted in some various Si/Al molar ratios from 0.90; 1.00.; 1.05; to 1.24. The zeolite A was then analyzed using XRD and XRF. The best zeolite A based on XRD result is zeolite with Si/Al molar ratio of 1.1 with crystallinity of 96,80%. The x-ray fluorescence result showed that the Si/Al molar ratios of the four zeolite samples were close to of Si/Al molar ratios of 1, 1.1, 1.21.3 respectively.Keywords: Fly ash, Zeolite A, Hydrothermal Fusion


Sign in / Sign up

Export Citation Format

Share Document