Comparative study of hydrothermal synthesis routes of zeolite A

Veģere, Kristīne; Kravcevica, Rita; Krauklis, Andrey E.; Juhna, Tālis

doi:10.1016/j.matpr.2020.06.326

Cited by 11 publications

(3 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Likewise, the band at 3429.43 cm -1 corresponded to the O-H stretching was still exist. However, there was the band shift from 1421.54 to 1,425.40 cm -1 contributed to the CH3 stretching, from 2922.16 to 2937.59 cm -1 corresponded to the CH, and from 667.37 to 671.23 cm -1 corresponded to the symmetrical stretching in zeolite [45][46][47]. This is due to the overlap of the zeolite-chitosan structures through the active siloxane group in the zeolite [48].…”

Section: -2-fourier Transform Infrared (Ftir) Spectrometry Analysismentioning

confidence: 94%

The Effect of Zeolite/Chitosan Hybrid Matrix for Thermal-stabilization Enhancement on the Immobilization of Aspergillus fumigatus α-Amylase

et al. 2022

View full text Add to dashboard Cite

In this paper, the A. fumigatus α-amylase had been immobilized onto zeolite/chitosan hybrid to improve its thermal-stabilization for industrial needs. The methods applied enzyme production, isolation, partial purification, immobilization, and characterization. The optimum temperatures of the native and immobilized enzymes were 50 and 55˚C, respectively. The native enzyme has KM of 3.478 ± 0.271 mg mL-1 substrate and Vmax of 2.211± 0.096 µmole mL-1 min-1, while the immobilized enzyme has KM value of 12.051 ± 4.949 mg mL-1 substrate and Vmax of 1.602 ± 0.576 µmole mL-1 min-1. The residual activity of the immobilized enzyme retained up 10.97% after fifth reuse cycles. The native enzyme has ΔGi of 104.35 ± 1.09 kJ mole-1 and t½ of 38.75 ± 1.53 min, while the immobilized enzyme has ΔGi of 108.03 ± 0.05 kJ mole-1 and t½ of 180.03 ± 3.31 min. According to the increase in half-life (t½), stability improvement of the A. fumigatusα-amylase was 4.65 times greater than the native enzyme. Thus, the zeolite/chitosan hybrid is used as a new supporting matrix for further enzyme immobilization to stabilize the enzymes. Doi: 10.28991/ESJ-2022-06-03-06 Full Text: PDF

show abstract

Section: -2-fourier Transform Infrared (Ftir) Spectrometry Analysismentioning

confidence: 94%

The Effect of Zeolite/Chitosan Hybrid Matrix for Thermal-stabilization Enhancement on the Immobilization of Aspergillus fumigatus α-Amylase

et al. 2022

View full text Add to dashboard Cite

show abstract

“…At the second stage biogas is upgraded to biomethane using pressure swing adsorption (PSA) or membrane separation technologies. Zeolites adsorb strongly carbon dioxide and weaker -methane, therefore it can be applied as an effective CO2 adsorbent in PSA applications [8]. Another promising approach is currently seen in cryogenic upgrading technologies, in which simultaneously can be obtained high-purity biomethane and food-grade CO2 [9].…”

Section: Biogas Upgradingtraditional Methodsmentioning

confidence: 99%

Hydrogen supported bioconversion of biogas CO₂ to upgrade biomethane in fuel for vehicles: Recent findings in farmers survey

Kleperis¹,

Dimanta²,

Sloka³

et al. 2021

20th International Scientific Conference Engineering for Rural Development Proceedings

View full text Add to dashboard Cite

Biogas is a fuel obtained from organic waste fermentation in an anaerobic digestion plant and can be burned in a cogeneration unit to produce heat and electricity. In Latvia, biogas plants are popular among farmers, as electricity is mostly sold to the centralized electricity grid, receiving a subsidy in the form of a mandatory procurement component. Political circles are discussing the reduction or even abolition of this support, so the question of where to put the produced biogas is topical. Recently, many European countries have incentivized the production of biomethane to be injected into natural gas grids or compressed and used as biofuel in vehicles. The implementation of biogas upgrading unit into an existing anaerobic digestion plant to convert biogas to biomethane (<97%) can be performed by means of various technologies, physical and chemical absorption, adsorption, membrane and cryogenic separation. There are also biological pathways for biogas upgrading -biological conversion of residual CO2 and external hydrogen to methane carried out by hydrogenotrophic methanogens. The aim of this research is to give a review about latest developments in technologies and update views of biogas producers on possible upgrading of bio-methane concentration in the fermentation process. The main research results have indicated that farmers have interest in technological achievements of biological CO2 reformation, as well as specific changes in the fermentation process. They are supporting production of new kind of renewable fuel with possible application for vehicles, also indicate high costs in reformation and mechanical separation processes.

show abstract

“…The hydrothermal synthesis of zeolite A was generally carried out at a temperature of 90 to 120 • C for several hours. Previous research [13,14] indicated that excess energy was consumed under conventional hydrothermal synthesis temperatures (90~110 • C), and the hydroxy sodalite phases were formed along with the crystallization time being further prolonged. In the past decades, zeolite A was successfully obtained at room temperature [15][16][17][18].…”

Section: Introductionmentioning

confidence: 99%

Insight into the Growth Mechanism of Low-Temperature Synthesis of High-Purity Lithium Slag-Based Zeolite A

Li,

Xu,

Liu

et al. 2024

Materials

View full text Add to dashboard Cite

The utilization of lithium slag (LS), a solid waste generated during the production of lithium carbonate, poses challenges due to its high sulfur content. This study presents a novel approach to enhancing the value of LS by employing alkali fusion and hydrothermal synthesis techniques to produce zeolite A at low temperatures. The synthesis of high-purity and crystalline lithium-slag-based zeolite A (LSZ) at 60 °C is reported for the first time in this research. The phase, morphology, particle size, and structure of LSZ were characterized by XRD, SEM, TEM, N2 adsorption, and UV Raman spectroscopy, respectively. High-purity and crystalline zeolite A was successfully obtained under hydrothermal conditions of 60 °C, an NaOH concentration of 2.0 mol/L, and a hydrothermal time of 8 h. The samples synthesized at 60 °C exhibited better controllability and almost no byproduct of sodalite occurred compared to zeolite A synthesized at room temperature or conventional temperature (approximately 90 °C). Additionally, the growth mechanism of LSZ was elucidated, challenging the traditional understanding of utilization of lithium and enabling the synthesis of various zeolites at lower temperatures.

show abstract

Comparative study of hydrothermal synthesis routes of zeolite A

Cited by 11 publications

References 14 publications

The Effect of Zeolite/Chitosan Hybrid Matrix for Thermal-stabilization Enhancement on the Immobilization of Aspergillus fumigatus α-Amylase

The Effect of Zeolite/Chitosan Hybrid Matrix for Thermal-stabilization Enhancement on the Immobilization of Aspergillus fumigatus α-Amylase

Hydrogen supported bioconversion of biogas CO₂ to upgrade biomethane in fuel for vehicles: Recent findings in farmers survey

Insight into the Growth Mechanism of Low-Temperature Synthesis of High-Purity Lithium Slag-Based Zeolite A

Contact Info

Product

Resources

About

Comparative study of hydrothermal synthesis routes of zeolite A

Cited by 11 publications

References 14 publications

The Effect of Zeolite/Chitosan Hybrid Matrix for Thermal-stabilization Enhancement on the Immobilization of Aspergillus fumigatus α-Amylase

The Effect of Zeolite/Chitosan Hybrid Matrix for Thermal-stabilization Enhancement on the Immobilization of Aspergillus fumigatus α-Amylase

Hydrogen supported bioconversion of biogas CO2 to upgrade biomethane in fuel for vehicles: Recent findings in farmers survey

Insight into the Growth Mechanism of Low-Temperature Synthesis of High-Purity Lithium Slag-Based Zeolite A

Contact Info

Product

Resources

About

Hydrogen supported bioconversion of biogas CO₂ to upgrade biomethane in fuel for vehicles: Recent findings in farmers survey