scholarly journals Influence of Ethanol Concentration and Template Ion Exchange Agent on Template Recycling in Mobil Crystalline Material 41 (MCM-41) Synthesis

2020 ◽  
Vol 19 (2) ◽  
pp. 130
Author(s):  
Jia Yen Lai ◽  
Lock Hei Ngu ◽  
Farouq Twaiq
Keyword(s):  
Ion Exchange ◽  
Ethanol Concentration ◽  
Nitrogen Adsorption ◽  
Crystalline Material ◽  
Hexadecyltrimethylammonium Bromide ◽  
Water Mixture ◽  
Extract Solution ◽  
Exchange Agent ◽  
Synthesis Solution ◽  
Mcm 41

Recycling of surfactant template for several subsequent MCM-41 synthesis is necessary to reduce substantial synthesis solution disposal. In MCM-41 synthesis, ethanol concentration and template ion exchange agent are two significant factors that affect the silicate polymerization, solvating effect on micelles formation, and MCM-41 mesostructure formation. In view of that, this study investigates recycling of surfactant template ions in extract solution in Mobil Crystalline Material 41 (MCM-41) synthesis. Effect of the ethanol concentrations in the solution gel and the types of ion exchange agents on the yield of MCM-41 material and its surface morphology were studied. Hexadecyltrimethylammonium bromide was used as template for MCM-41 synthesis using tetraethylorthosilicate (TEOS) as silica reagent with ethanol-water mixture as solvent at different ethanol concentrations. Template ions of synthesis gel was exchanged with an ion exchange agent (i.e., 1-butyl-3-methylimidazolium chloride or ammonium nitrate) before it is extracted using synthesis solution. After extraction, the extracting solution was added with TEOS, used for second synthesis cycle and the process continued in an extraction. The template ions in the extract solution were further recycled up to eight synthesis cycles. Yield of calcined materials significantly influenced by ethanol solvent concentrations and however did not vary with various ion exchange agents. Nitrogen adsorption isotherms showed that the calcined materials exhibit MCM-41 characteristics with surface areas ranging from 600 – 1000 m2/g. It is possible to recycle and reuse the surfactant template for several subsequent times of preparing MCM-41 if the ethanol concentration in the solution gel controlled continuously.

scholarly journals Template Recycling and Reuse in MCM-41 Synthesis: Statistical Study

2018 ◽  
Vol 5 (1) ◽  
pp. 213-226 ◽  
Author(s):  
Jia Yen Lai ◽  
Lock Hei Ngu ◽  
Farouq Twaiq
Keyword(s):  
Ion Exchange ◽  
Volume Fraction ◽  
Normal Probability Plot ◽  
Probability Plot ◽  
Normal Probability ◽  
Exchange Agent ◽  
Recycle And Reuse ◽  
Full Factorial ◽  
High Ethanol ◽  
Mcm 41

The recycle and reuse of template in MCM-41 synthesis were analysed using 23 full factorial design in order to study the effect of the template extraction parameters on the mass of MCM-41 powder produced. Four consecutive MCM-41 synthesis cycles utilizing the recycled template were studied with three factors that are ethanol fraction (A), amount of ion exchange agent (B) and the type of ion exchange agent (C). The significant effects contributed by the factors A, B and C and their interactions were identified through the half-normal probability plot and normal probability plot of the residuals. F-test and t-test were carried out to test the contribution of regression coefficients for synthesis cycles of MCM-41 synthesis models. AB interaction showed that larger mass of MCM-41 powder was obtained at high ethanol volume fraction and high quantity of ion exchange agent when either type of ion exchange agent was used.

Al-MCM-41 modified with carbonaceous deposits: characterisation by nitrogen adsorption measurements

2000 ◽  
Vol 2 (23) ◽  
pp. 5510-5516 ◽  
Author(s):  
Michal Rozwadowski ◽  
Maria Lezanska ◽  
Jerzy Wloch ◽  
Krzysztof Erdmann ◽  
Roman Golembiewski ◽  
...  
Keyword(s):  
Nitrogen Adsorption ◽  
Carbonaceous Deposits ◽  
Mcm 41

The effect of synthesis solution pH on the physicochemical properties of Co substituted MCM-41

2005 ◽  
Vol 34 (1-4) ◽  
pp. 31-40 ◽  
Author(s):  
Sangyun Lim ◽  
Yanhui Yang ◽  
Dragos Ciuparu ◽  
Chuan Wang ◽  
Yuan Chen ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Solution Ph ◽  
Synthesis Solution ◽  
Mcm 41

scholarly journals Noninvasive Determination of the Amount of Ethanol in Liquid Mixtures by Ultrasound Using Bilinear Interpolation Method

2019 ◽  
Vol 64 (1) ◽  
Author(s):  
Ahmet Aydın ◽  
Cemil Keskinoğlu ◽  
Umut Kökbaş ◽  
Abdullah Tuli
Keyword(s):  
Ethanol Concentration ◽  
Liquid Mixture ◽  
Interpolation Method ◽  
Ultrasonic Method ◽  
Liquid Mixtures ◽  
Water Mixture ◽  
Bilinear Interpolation ◽  
Destructive Effect ◽  
El Sistema

Ultrasound is used in many analysis studies, including liquid mixtures. Many mixtures are analyzed to understand their contents or properties in different situations. One of these mixtures is the ethanol-water combination. In this study, the amount of ethanol in the liquid mixture was determined noninvasively by the ultrasonic method using a microcontroller-based system. The results show that the measurements obtained were within the p<0.05 confidence interval. The characteristics evaluation of the system shows that the system can detect ethanol concentration as low as 0.552 g/L, thus the system has a broad and linear determination range for ethanol. Although the system is calibrated and tested with ethanol-water mixture, it can be used for any mixture that changes density related to the substance concentration, including different alcohols which are soluble in water (glycols, glycoethers, etc.) or any other material (solid or liquid) which is soluble in alcohol or different liquid solvent. The system has so many advantages that make it possible to use comfortably in many areas where the amount of ethanol contained in the mixture is essential. These advantages are the high accuracy and sensitivity, being noninvasive, portable, and not having a destructive effect on the substance.   Resumen. El ultrasonido es utilizado en muchos estudios incluyendo las mezclas liquidas. Se analizan varias mezclas para entender sus contenidos y propiedades en diferentes situaciones. Una de estas mezclas es la combinación de etanol-agua. En este estudio, la cantidad de etanol en la mezcla líquida fue determinada de manera no invasiva con el método ultrasonico utilizando un sistema basado en microcontrolador. Los resultados muestran que las mediciones obtenidas se encontraban dentro de un intervalo de confianza de p<0.05. Las características de evaluación del sistema muestran que se puede detectar etanol a una concentración tan baja como 0.552 g/L, por lo tanto, el sistema tiene un rango de determinación linear amplio para etanol. Aunque el sistema se calibra y prueba con mezcla de etanol-agua, puede ser utilizado para cualquier mezcla que cambia de densidad en relación con la concentración de la substancia, incluyendo diferentes alcoholes que son solubles en agua (glicoles, glicoeteres, etc) o cualquier otro material (sólido o líquido) que sea soluble en alcohol o en algún solvente líquido diferente. El sistema tiene muchas ventajas que hacen posible su utilización en muchas áreas donde la cantidad de etanol contenida en la mezcla es esencial. Estas ventajas son de alta precisión y sensiblididad al ser no invasivo, portátil y al no tener un efecto destructivo sobre la sustancia.

scholarly journals THE INFLUENCE OF Si/Al MOLE RATIO OF PRECURSOR SOLUTION ON THE STRUCTURAL PROPERTIES OF MCM-41 FROM FLY ASH

2010 ◽  
Vol 3 (2) ◽  
pp. 126-134
Author(s):  
Sutarno Sutarno ◽  
Yateman Arryanto ◽  
Stefani Wigati
Keyword(s):  
Fly Ash ◽  
Structural Properties ◽  
Sodium Silicate ◽  
Precursor Solution ◽  
Ammonium Hydroxide ◽  
Pore Wall ◽  
Nitrogen Adsorption ◽  
Average Pore ◽  
Xrd Pattern ◽  
Mcm 41

The synthesis of MCM-41 from fly ash was done hydrothermally at 100°C for 72 hours using supernatant of fly ash solution, sodium silicate, tetramethylammonium hydroxide (TMAOH) and cetyltrimethyl-ammonium hydroxide (CTMAOH) surfactants. The effect of Si/Al mole ratio of precursor solution on the structural properties of MCM-41 was studied by variation of the volume composition of supernatant and sodium silicate. The surfactant was removed by calcination at 550°C for 5 hours with heating rate 2°C/minute. The as-synthesized products were characterized by X-ray diffraction, infrared spectroscopy, and nitrogen adsorption methods. The XRD pattern proved that the samples were MCM-41 and the higher the Si/Al mole ratio of precursor solution resulted MCM-41 with higher crystallinity. Calcination was able to remove the CTMAOH surfactant. It was identified by the disappearance of the peak at 3000-2850 cm-1, which is characteristic for CTMAOH. The XRD pattern of calcined MCM-41 showed the decrease of dspacing  and the increase of crystallinity. MCM-41 synthesized with Si/Al mole ratio of precursor solution=44.5 showed the highest crystallinity and has specific surface area=694.5 m2/g, average pore diameter=35Å and pore wall thickness=13.6Å.   Keywords: fly ash, Si/Al mole ratio, MCM-41, crystallinity

Rapid Synthesis of MCM-41 from Rice Husk Using Ultrasonic Wave: Optimation of Sonication Time

2019 ◽  
Vol 948 ◽  
pp. 198-205
Author(s):  
Suyanta Suyanta ◽  
Eko Sri Kunarti ◽  
Bambang Rusdiarso ◽  
Dritta Anies Cahaya ◽  
Efa Radnawati ◽  
...  
Keyword(s):  
Optimum Condition ◽  
Ultrasonic Wave ◽  
Rice Husk ◽  
Nitrogen Adsorption ◽  
Sonication Time ◽  
Ultrasound Waves ◽  
Comb Structure ◽  
Silica Source ◽  
Adsorption Desorption ◽  
Mcm 41

Ultrasound waves with 48 KHz of frequency were applied for the synthesis of MCM-41 using rice husk as the silica source. The effect of sonication time (30, 60, 90, 120, 150, 180, and 210 min) on the crystallinity of calcined MCM-41 was investigated. Characterization using XRD and FTIR indicated that the ordered structure of MCM-41 could be synthesized by ultrasonic wave. Sonication time at 150 min was found to be the optimum condition. The nitrogen adsorption-desorption isotherms informed that the mesoporous material produced at the optimum condition has 794.73 m2·g-1of surface area, 3.02 nm of BJH pore diameter, 1.17 nm of wall thickness, and 0.68 ml·g-1 of pore volume. While based on the TEM image, the material has hexagonal or a honey-comb structure.

Ion Exchange Behavior of the Febex Bentonite: 2. Batch Experiments and Geochemical Modeling

2000 ◽  
Vol 663 ◽  
Author(s):  
J. Delgado ◽  
P. Carretero ◽  
R. Juncosa ◽  
J. Samper ◽  
F.J. Huertas ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Geochemical Modeling ◽  
Geochemical Evolution ◽  
Water Mixture ◽  
Total Inorganic Carbon ◽  
Exchange Reactions ◽  
Major Cations ◽  
Different Temperatures ◽  
Good Agreement

ABSTRACTIon exchange experiments have been performed with the FEBEX bentonite. Five grams of dry powder of this clay were put inside dialysis bags, which were located inside PFA reactors filled with 125 ml of water of a given chemical composition (Moody, Grimsel, and bentonitic-granitic type waters). The reactors containing the clay powder/water mixture were heated to different temperatures (from room temperature up to 80°C) along a time span ranging from 1 day to 1 year. Water was renewed according to a prescribed schedule but not the clay, which remained in place for the whole extent of each test. After each water renewal, major cations, silica, total inorganic carbon, and pH were analyzed. At the end of each test, the exchange complex and CEC of the bentonite were measured. These experiments have been modeled with a conveniently modified version of the EQ3/6 software package where ion exchange reactions were formulated as half reactions and added to its database. In general, model results are in fairly good agreement with experimental data, especially in the case of dissolved cations. Computed values of exchanged concentrations also match the measurements, although in some cases they deviate from them. The fact that the numerical results reproduce the observed patterns of exchange tests indicates that the adopted geochemical conceptual model is appropriate. Some features of the geochemical evolution of these tests also take place at the “mock-up” and “in situ” FEBEX tests.

Determination of the Lamellar Phase Content in MCM-41 Using X-ray Diffraction, Nitrogen Adsorption, and Thermogravimetry

2000 ◽  
Vol 104 (7) ◽  
pp. 1581-1589 ◽  
Author(s):  
Michal Kruk ◽  
Mietek Jaroniec ◽  
Yong Yang ◽  
Abdelhamid Sayari
Keyword(s):  
Nitrogen Adsorption ◽  
Lamellar Phase ◽  
Phase Content ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mcm 41
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