Nanostructured Natural Zeolite: Surface Area, Meso-pore and Volume Distribution, and Morphology

2014 ◽  
Vol 45 (22) ◽  
pp. 2878-2897 ◽  
Author(s):  
K. Ramesh ◽  
K. Sammi Reddy ◽  
I. Rashmi ◽  
A. K. Biswas
Author(s):  
Reza Yazdanpanah ◽  
Eshagh Moradiyan ◽  
Rouein Halladj ◽  
Sima Askari

Aim and Objective: The research focuses on recent progress in the production of light olefins. Hence, the common catalyst of the reaction (SAPO-34) deactivates quickly because of coke formation, we reorganized the mechanism combining SAPO-34 with a natural zeolite in order to delay the deactivation time. Materials and Methods: The synthesis of nanocomposite catalyst was conducted hydrothermally using experimental design. Firstly, Clinoptilolite was modified using nitric acid in order to achieve nano scaled material. Then, the initial gel of the SAPO-34 was prepared using DEA, aluminum isopropoxide, phosphoric acid and TEOS as the organic template, sources of Aluminum, Phosphor, and Silicate, respectively. Finally, the modified zeolite was combined with SAPO-34's gel. Results: 20 different catalysts due to D-Optimal design were synthesized and the nanocomposite with 50 weight percent of SAPO-34, 4 hours Crystallization and early Clinoptilolite precipitation showed the highest relative crystallinity, partly high BET surface area and hierarchical structure. Conclusion: Different analysis illustrated the existence of both components. The most important property alteration of nanocomposite was the increment of pore mean diameters and reduction in pore volumes in comparison with free SAPO-34. Due to low price of Clinoptilolite, the new catalyst develops the economy of the process. Using this composite, according to formation of multi-sized pores located hierarchically on the surface of the catalyst and increased surface area, significant amounts of Ethylene and Propylene, in comparison with free SAPO-34, were produced, as well as deactivation time that was improved.


Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 217
Author(s):  
Marin Ugrina ◽  
Martin Gaberšek ◽  
Aleksandra Daković ◽  
Ivona Nuić

Sulfur-impregnated zeolite has been obtained from the natural zeolite clinoptilolite by chemical modification with Na2S at 150 °C. The purpose of zeolite impregnation was to enhance the sorption of Hg(II) from aqueous solutions. Chemical analysis, acid and basic properties determined by Bohem’s method, chemical behavior at different pHo values, zeta potential, cation-exchange capacity (CEC), specific surface area, X-ray powder diffraction (XRPD), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), as well as thermogravimetry with derivative thermogravimetry (TG-DTG) were used for detailed comparative mineralogical and physico-chemical characterization of natural and sulfur-impregnated zeolites. Results revealed that the surface of the natural zeolite was successfully impregnated with sulfur species in the form of FeS and CaS. Chemical modification caused an increase in basicity and the net negative surface charge due to an increase in oxygen-containing functional groups as well as a decrease in specific surface area and crystallinity due to the formation of sulfur-containing clusters at the zeolite surface. The sorption of Hg(II) species onto the sulfur-impregnated zeolite was affected by the pH, solid/liquid ratio, initial Hg(II) concentration, and contact time. The optimal sorption conditions were determined as pH 2, a solid/liquid ratio of 10 g/L, and a contact time of 800 min. The maximum obtained sorption capacity of the sulfur-impregnated zeolite toward Hg(II) was 1.02 mmol/g. The sorption mechanism of Hg(II) onto the sulfur-impregnated zeolite involves electrostatic attraction, ion exchange, and surface complexation, accompanied by co-precipitation of Hg(II) in the form of HgS. It was found that sulfur-impregnation enhanced the sorption of Hg(II) by 3.6 times compared to the natural zeolite. The leaching test indicated the retention of Hg(II) in the zeolite structure over a wide pH range, making this sulfur-impregnated sorbent a promising material for the remediation of a mercury-polluted environment.


Clay Minerals ◽  
2011 ◽  
Vol 46 (2) ◽  
pp. 241-250 ◽  
Author(s):  
V. Lilkov ◽  
O. Petrov ◽  
V. Petkova ◽  
N. Petrova ◽  
Y. Tzvetanova

AbstractThis paper presents results from comparative thermogravimetric, calorimetric and pozzolanic activity analyses of five natural zeolite samples from Bulgaria, Slovakia, Philippines, USA and North Korea. The zeolites actively participate in the hydration processes of cement. Their activity in the early stage of hydration is based mainly on the large surface area of the particles while, in the later stages of activation, chemical reactions occur between the products of the hydration of cement and the soluble SiO2 that is present in the bulk of the zeolites. It has been shown that in all cement pastes which contain zeolite additives, the quantity of portlandite is lower than that in pure cement paste or is even totally absent. The amounts of hydration products are greater when 30% zeolite is used than when 10% zeolite is added (excluding the sample with chabazite). The lowest pozzolanic activity is shown by chabazite, which possessed the lowest SiO2/Al2O2 ratio.


2010 ◽  
Vol 3 (2) ◽  
pp. 91-97 ◽  
Author(s):  
Eddy Heraldy ◽  
Hisyam SW ◽  
Sulistiyono Sulistiyono

Characterization and activation of Natural Zeolite from Ponorogo (ZAP) have been done to improve the quality of zeolite as porous material. Analysis of mineral composition is done using X-Ray Difraction (XRD), Fourier Transform-Infra Red (FTIR) Spectroscopy and metal analysis using Atomic Absorption Spectroscopy (AAS). Characterization of the activated zeolite covered about number of acidic sites, surface area, ratio Si/Al and metal composition (Na, Ca, K and Fe). Activated processes is done using various mineral acid, i.e HCl, HNO3, H2SO4 and HPO4 with each concentration at 1 M and 3 3 hours dipping. The result showed that ZAP has composition Ca-klinoptilolit (43.09 %), gismondin (17.57 %), modernit (4.21 %) and quartz (10.37 %). The most efectif of the acid to activate is HCl and is proved to absorp of Zn in waste water. The effect of chemical activation is increasing the ratio of Si/Al, increasing the surface area and reducing some metal composition.   Keywords: natural zeolite, chemical activation, porous material


2019 ◽  
Vol 56 (3) ◽  
pp. 803-809 ◽  
Author(s):  
Eleanor Olegario ◽  
Jenichi Clairvaux Felizco ◽  
Christian Mark Pelicano ◽  
Herman Mendoza ◽  
Hideki Nakajima

2018 ◽  
Author(s):  
Lorenzo Albanese ◽  
Silvia Baronti ◽  
Francesca Liguori ◽  
Francesco Meneguzzo ◽  
Pierluigi Barbaro ◽  
...  

The effectivity of biochar as soil amendment is depending by its physical and chemical characteristics that are related to the type and the features of the thermal production process, such as peak temperature, heating rate, holding time, as well as from the used feedstocks. The textural characteristics of biochar in term of surface area, pore size and pore volume distribution, important for the physicochemical properties of the material, are critically dependent on the production process and the feedstock type. In this study, based on a single biochar type and a single experiment, for the first time controlled hydrodynamic cavitation was proven as a fast and effective way to enhance the biochar surface area by as much as 120%, while preserving or improving the respective chemical composition, showing far higher efficiency than the conventional increase of the peak pyrolysis temperature.


ALCHEMY ◽  
2015 ◽  
Vol 4 (1) ◽  
Author(s):  
Dwi Putri W. Pamungkas ◽  
Suci Amalia ◽  
Susi Nurul Khalifah

<p>Studied the characteristics of natural zeolite catalysts activated and modifications and catalytic activity in the isomerization of glucose. Natural zeolite was activated by NH<sub>4</sub>NO<sub>3</sub> 2 M obtained catalyst HZA. While modification using 0,24 M Sn metal impregnated on HZA obtained catalyst Sn-HZA. At this stage, hydrothermal process carried out at temperature of 90 °C for 12 hours followed by calcination at temperature of 500 °C for 4 hours. The characterization includes the XRD analysis, SEM-EDAX analysis, acidity by ammonia method, and surface area by adsorption of methylene blue method. Glucose conversion was obtained through analysis of polarimeter at hour-0, 1, 2, 3, and 4 with temperature variation of 110, 120, and 130 °C. Solution which had the highest conversion resulted by polarimeter was analyzed by HPLC. XRD analysis showed that there were no changes in the structure of zeolite after activation and modification process. SEM-EDAX analysis showed that morphology of the zeolite surface is not damaged and Sn metal was successfully impregnated 6,94 %. The activity of HZA and Sn-HZA was 1,4850 mmol/g and 2,3145 mmol/g. while the surface area of HZA and Sn-HZA was 11,4077 m<sup>2</sup>/g and 11,4738 m<sup>2</sup>/g. Using the Sn-HZA catalyst with the reaction temperature of 120 °C provides the highest conversion of glucose and fructose selectivity. It were 14,0733 % w/v and 0,646 % w/v.<em>  </em></p><p class="BodyAbstract"> </p><strong><em>Keywords</em>:</strong> <em>Catalyst, glucose, isomerization, natural zeolite, Sn metal.</em>


2020 ◽  
Vol 57 (3) ◽  
pp. 40-47
Author(s):  
M. Sirait ◽  
K.Sari Dewi Saragih ◽  
S. Gea ◽  

AbstractHeavy metal waste is very dangerous, which can change the condition of water into a solid substance that can be suspended in water and can reduce the cleanliness level of water consumed by living things. To date, heavy metals can be managed through several processes, namely physics, biology or chemistry. One of the ways to overcome heavy metal pollution is to use natural zeolite applying a co-precipitation method, as it is known that zeolite is a powerful natural material to be used for certain purposes. In order to justify the research results, several analyses have been performed, such as X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Surface Area Analyser (SAA), and Atomic Adsorption Spectrophotometric (AAS). From the XRD results, it has been found out that the size of each zeolite with variations in size of 150 mesh, 200 mesh, and 250 mesh is 29.274 nm, 38.665 nm and 43.863 nm, respectively. Moreover, the SEM-EDX has shown that the zeolite under consideration is a type of Na-Zeolite and that the co-precipitation method successfully removes impurity elements, namely, Fe, Ti, and Cl. The results of SAA testing have indicated that the total surface area for each variation of zeolite sizes is 63.23 m2/g, 45.14 m2/g and 59.76 m2/g. The results of the AAS test analysis have demonstrated that the optimal absorption of metal content is observed in a size of 150 mesh zeolite with adsorption power of 99.6 % for Pb metal, 98 % for Cu metal, and 96 % Zn metal.


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