The Physicochemical Properties Of Vpi-7: A Microporous Zincosilicate With Three-Membered Rings

1991 ◽  
Vol 233 ◽  
Author(s):  
Michael J. Annen ◽  
Mark E. Davis ◽  
John B. Higgins ◽  
John L. Schlenker
Keyword(s):  
Physicochemical Properties ◽  
Molecular Sieve ◽  
Natural Zeolite ◽  
Toxic Compounds ◽  
Void Volumes ◽  
Framework Density ◽  
Synthesis Of Materials

ABSTRACTThe synthesis of materials with void volumes in excess of 50% is an ongoing challenge in molecular sieve science. It has been shown that a correlation exists between the minimum framework density (FD) and the smallest ring in which all tetrahedral atoms reside (MINR). Based on this evidence it appears that materials containing 3-membered rings (3MR) will be necessary in order to obtain FDs lower than those currently attainable. Several framework beryllosilicate minerals including the natural zeolite, lovdarite, contain 3MRs. Unfortunately, beryllium can form highly toxic compounds that limit its suitability for many applications. Thus, in this study we have searched for a replacement for Be and have found that zinc is a suitable substitute with respect to the formation of three-membered rings.We report here VPI-7, a novel zincosilicate molecular sieve which contains three-membered rings. The VPI-7 framework contains rings composed of 3–, 4– and 5 T-atoms which form unidimensional 8– and intersecting 9MR channels.

Effect of Synthesis Duration on the Physicochemical Properties of Siliceous Mesoporous Molecular Sieve (Si-MMS)

2012 ◽  
Vol 326-328 ◽  
pp. 647-653 ◽  
Author(s):  
Anita Ramli ◽  
Sohail Ahmed ◽  
Suzana Yusup
Keyword(s):  
Physicochemical Properties ◽  
Pore Structure ◽  
Molecular Sieve ◽  
Mesoporous Material ◽  
Mesoporous Molecular Sieve ◽  
Diffraction Peaks ◽  
Adsorption Desorption ◽  
Synthesized Materials ◽  
Synthesis Duration ◽  
Mcm 41

Pure silica mesoporous molecular sieve (MMS) solid has been synthesized at 100°C by hydrothermal process. The effect of synthesis duration from 2 to 10 days has been investigated on the physicochemical properties of mesoporous molecular sieve. Samples were characterized by low angle XRD, N2adsorption-desorption and HRTEM analysis. XRD patterns of the as-synthesized samples showed four well-defined diffraction peaks corresponding to 100, 110, 200 and 210 planes. These peaks are the fingerprint characteristics of MCM-41 mesoporous material. The high intensity diffraction peaks were observed in 8-days sample that define the high ordering of the pores and long range order. N2adsorption-desorption results showed that all samples possessed a type IV isotherm having hysteresis loop of typeH1which is an identification of mesoporous material. Calcined samples exhibited high surface area i.e., 984-1036 m2g-1, pore volume i.e., 1.00-1.13 cm3g-1and average pore diameter i.e., 3.04-3.30 nm. A hexagonal pore structure was found in the synthesized materials by HRTEM analysis, which confirms that the synthesized materials are MCM-41. HRTEM analysis showed the effect of synthesis duration on the materials and found that 8-days sample exhibited highly ordered hexagonal pore structure like honeycomb structure. All the samples were calcined at 550°C to remove the template and to study the changes in the mesoporous framework. The results showed that the mesoporous structure remained intact after calcination at 550°C, indicating that the mesoporous materials exhibit high thermal stability.

scholarly journals Bioethanol Dehydration Process using NaOH-Activated Zeolite at Various Concentration and Zeolite Weight

ALCHEMY ◽  
2015 ◽  
Vol 4 (1) ◽  
Author(s):  
David Saidi ◽  
Akyunul Jannah ◽  
Anik Maunatin
Keyword(s):  
Molecular Sieve ◽  
Natural Zeolite ◽  
Fermentation Process ◽  
Fossil Fuel ◽  
Basic Material ◽  
Dehydration Process ◽  
Distillation Method ◽  
Chromatography Method ◽  
Naoh Solution ◽  
Glass Beaker

<p>Utilization of molasses as basic material for producing bioethanol becomes one of the promising efforts to fulfill the demand of fuel and diminish the dependence upon fossil fuel that its availability is increasingly rare. However, ethanol produced from fermentation of molasses has low purity. The purity could be increased by using dehydration method and zeolite activated by NaOH and alum as alumina source. The research is aimed to know the dehydration process of bioethanol use NaOH-activated zeolite at various concentration and zeolite weight on the purification of bioethanol. In this research, the experiments could be categorized into 4 groups, they are activation of zeolite, fermentation, distillation, and dehydration process. Activation of natural zeolite performed by entering of sized 120-150 mesh zeolite powder was added to glass beaker that contains  NaOH aqueous solution and followed by adding alum which took place at 80 ˚C for 8 hours and the final product calcinated at 600 ˚ C for 2 hour. Fermentation process was managed for 6 days and pH 5. Furthermore, bioethanol was separated by distillation method at 78,5 - 85 ˚C and followed by molecular sieve dehydration using zeolite activated by NaOH solution in variation of zeolite weight (30, 40 and 50 %) and NaOH concentration (1, 2, 3 dan 4 M). The amount of bioethanol was measured by gas chromatography method. Bioethanol concentration as fermentation product is 29,8 %. The result revealed that dehydration with 30% w.t zeolite activated by 2 M NaOH solution had the best activity in bioethanol purification with amount of bioethanol is 53,76 %, Increased Levels of Bioethanol (ILB) value is 80,39 % and Adsorption Capacity of Zeolite (ACZ) is 399,31 %.</p><p>Keywords: bioethanol, concentration of NaOH, dehydration, molasses, molecular sieve, weight of zeolite</p>

scholarly journals Efektivitas Zeolit Alam Ende-NTT sebagai Adsorben dalam Pemurnian Bioetanol Berbahan Baku Moke: Minuman Tradisional Flores

2020 ◽  
Vol 4 (2) ◽  
pp. 121
Author(s):  
Yulius Dala Ngapa ◽  
Jumilah Gago
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Molecular Sieve ◽  
Natural Zeolite ◽  
Alternative Energy ◽  
Adsorption Process ◽  
Activation Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

Ketergantungan akan pemakaian bahan bakar fosil yang terus meningkat telah mengubah pola pikir manusia untuk mengembangkan penelitian terkait energi alternatif terbarukan. Bioetanol yang berasal dari hasil fermentasi nira tanaman aren (Arenga pinnata MERR), dan dikenal sebagai minuman tradisional Moke di Flores dapat dimanfaatkan sebagai bahan bakar alternatif jika memiliki kemurnian di atas 99,5%. Proses adsorpsi merupakan salah satu metode yang dilakukan untuk menghasilkan bioetanol dengan kadar di atas titik azeotrop. Adsorben yang efektif digunakan sebagai molecular sieve adalah zeolit alam yang berasal dari kabupaten Ende – NTT. Peningkatan efisiensi penyerapan zeolit alam dalam pemurnian bioetanol berbahan baku Moke sudah dilakukan melalui proses aktivasi kimia. Penelitian ini bertujuan untuk mengetahui kadar dan kualitas bioetanol setelah pemurnian menggunakan adsorben zeolit alam Ende – NTT yang telah diaktivasi NaOH pada berbagai konsentrasi. Kadar bioetanol yang terdapat pada Moke sebelum dan sesudah proses adsorpsi ditentukan dengan instrumen gas kromatografi, karakterisasi zeolit alam menggunakan X-Ray Diffraction (XRD) dan Scanning Electron Microscope (SEM). Zeolit alam Ende dapat digunakan sebagai adsorben dalam meningkatkan kadar bioetanol berbahan baku Moke.The reliance on increasing use of fossil fuels has changed the human mindset to develop research related to renewable alternative energy. Bioethanol derived from fermented palm sugar sap (Arenga pinnata MERR), and known as Moke, traditional drink in Flores can be used as an alternative fuel if it has a purity above 99.5%. The adsorption process is one method used to produce bioethanol with a level above the azeotrope point. The effective adsorbent used as molecular sieve is natural zeolite originating from Ende - NTT. Increased efficiency of absorption of natural zeolite in bioethanol purification made from Moke has been done through a chemical activation process. This study aims to determine the level and quality of bioethanol after purification using Ende-NTT natural zeolite adsorbent which has been activated by NaOH at various concentrations. Bioethanol levels found in the Moke before and after the adsorption process were determined by gas chromatography instruments, natural zeolite characterization using X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM). Ende natural zeolite can be used as an adsorbent to increase the level of bioethanol made from Moke.

scholarly journals Propiedades Básicas de Zeolitas Naturales de Panamá con Potencial de Desarrollo Industrial

2018 ◽  
Vol 3 (1) ◽  
pp. 721
Author(s):  
Dr. Cecilio Hernández B. ◽  
M.Sc. Jorge Olmos ◽  
Licda. Yahaira Espinosa
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Cation Exchange ◽  
Volcanic Activity ◽  
Natural Zeolite ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Natural Zeolites ◽  
Low Levels ◽  
Initial Results

The initial results of the properties that have been determined to a sample of natural zeolite, coming from areas of volcanic activity of Panama, and that has been identified with potential for its industrial explotation, are presented. Some physicochemical properties, chemical composition and morphology were determined. A natural zeolite with an intermediate level of Si/Al (2.62), low levels of dissolved salts and a morphology with pores-shaped channels with a diameter of 5 mm are observed.Keywords: natural zeolites, chemisorption, morphology, macropores, cation exchange capacity

Effect of lanthanum species on the physicochemical properties of La/SAPO-11 molecular sieve

2017 ◽  
Vol 347 ◽  
pp. 170-184 ◽  
Author(s):  
Yuxiang Liu ◽  
Xinmei Liu ◽  
Lianming Zhao ◽  
Yuchao Lyu ◽  
Lu Xu ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Molecular Sieve

Physicochemical Properties and Catalytic Behavior of the Molecular Sieve SSZ-70

2010 ◽  
Vol 22 (8) ◽  
pp. 2563-2572 ◽  
Author(s):  
Raymond H. Archer ◽  
John R. Carpenter ◽  
Son-Jong Hwang ◽  
Allen W. Burton ◽  
Cong-Yan Chen ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Molecular Sieve ◽  
Catalytic Behavior

scholarly journals COMPOSITION AND MOLECULAR-SORPTION PROPERTIES OF THE ZEOLITE TUFF OF THE DEPOSITNEAR THE GREAT LULYA RIVER

2017 ◽  
Vol 13 (3) ◽  
pp. 21-25
Author(s):  
Tat'yana Nikolaevna Smorodinova ◽  
Margarita Kondrat'evna Kotvanova
Keyword(s):  
Phase Composition ◽  
Molecular Sieve ◽  
Natural Zeolite ◽  
Raw Materials ◽  
Sorption Properties ◽  
Dynamic Conditions ◽  
Molecular Sorption ◽  
Branched Structure ◽  
Zeolite Tuff ◽  
Area Of Application

The elemental and phase composition of the natural zeolite tuff of the deposit near the Great Lulya river have been studied. The molecular sieve properties of zeolite tuff under dynamic conditions on model mix- tures of C6-C14 hydrocarbons have been studied. The possibility of separation of hydrocarbons of a normal and branched structure is shown. Thus, one more area of application of natural regional raw materials has been revealed.

scholarly journals The effect of physicochemical properties of fuels on ecological parameters of a diesel engine

2017 ◽  
Vol 171 (4) ◽  
pp. 274-278
Author(s):  
Krzysztof BALAWENDER ◽  
Dariusz KONIECZNY ◽  
Hubert KUSZEWSKI ◽  
Kazimierz LEJDA ◽  
Krzysztof LEW ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Test Bench ◽  
Fuel Injection ◽  
Combustion Engine ◽  
Exhaust Gas ◽  
Toxic Compounds ◽  
Injection Process ◽  
Physicochemical Studies ◽  
Ecological Parameters ◽  
Reduce Emissions

The objective of the research results of which are presented in this paper was to determine the effect of selected physicochemical properties of fuels on ecological parameters of a diesl engine. Physicochemical parameters of fuel have a decisive effect on correct functioning, operating parameters, and cleanliness of the exhaust gas emitted to the environment by any combustion engine. Results of physicochemical studies can be useful in developing fuels blends of specific properties, whereas results obtained in the course of tests carried out on an engine test bench allow to optimize parameters of the fuel injection process with the aim to reduce emissions of toxic compounds to atmosphere.

Studies on γA-globulins and α2-macroglobulins. Characterization of γA- and α2-macroglobulins

1968 ◽  
Vol 46 (3) ◽  
pp. 211-216 ◽  
Author(s):  
Benjamin E. Sanders ◽  
Yang H. Oh
Keyword(s):  
Ion Exchange ◽  
Physicochemical Properties ◽  
Human Plasma ◽  
Molecular Sieve ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Normal Human Plasma ◽  
Γ Globulins ◽  
Normal Human

Fractionation into several individual components was achieved from Cohn's Fraction III of human plasma by the successive application of separation principles that depend on solubility, charge, and size (precipitation, ion-exchange chromatography, and molecular-sieve chromatography methods). Characterization was made by various electrophoretic procedures such as microzone on cellulose acetate, disc on acrylamide gel, and immunoelectrophoresis, and includes some physicochemical properties of the purified proteins. There are found to be various components of γ-globulins, α2-macroglobulins, β-glycoproteins, β-lipoproteins, and other minor proteins in Cohn's Fraction III of normal human plasma. The physicochemical properties of two γA-globulins and two α2-macroglobulins were investigated.

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