Synthesis and Preparation of Al-MCM-41 Mesoporous Materials Using Oil Shale Residue

2019 ◽  
Vol 944 ◽  
pp. 1192-1198
Author(s):  
Rong Wang ◽  
Zhi Xiang Lin ◽  
Yang Zhao ◽  
Xiao Dong Xu ◽  
Yan Xi Deng

An Al-supported cage-like mesoporous silica type MCM-41 has been prepared using a simple one-step synthetic procedure using oil shale residue and CTAB(Hexadecyl trimethyl Ammonium Bromide) as the template. The effects of temperature on the porosity, structure and surface area of Al-MCM-41 mesoporous materials were characterized by X-ray powder diffraction, N2adsorption desorption, scanning electron micrographs (SEM), transmission electron microscopy (TEM) techniques and Fourier transform infrared spectroscopy (FT-IR). The results indicated that temperature was a key to the characteristics of Al-MCM-41 materials, and when the temperature up to 333 K, Al-MCM-41 exhibited excellent characteristics with high degree of order, high surface area and pore volume. The one-step hydrothermal synthesized MCM-41 mesoporous material possessed high BET surface area, high pore size and high pore volume. They are respectively 835.1 m2/g, 32.6 Å and 1.22 cm3/g under the condition of the Si : Al =78:1, pH =10, crystallization temperature was 333K, crystallization time was 48h and calcination at 823 K for 5 h in air. All the results indicated the possibility of using oil shale residue as silicon and aluminum source to produce Al-MCM-41, and gave us a new way to recycle a solid waste. As well as this made it impossible to large-scale production of Al-MCM-41. Keywords: Al-MCM-41 mesoporous materials, oil shale residue, one-step synthesis

2014 ◽  
Vol 925 ◽  
pp. 23-27
Author(s):  
Nurhadijah Zainalabidin ◽  
Noor Hasyierah Mohd Salleh ◽  
Dachyar Arbain

Mesoporous materials are favorable for enzyme immobilization due to their unique properties of large surface area, uniform pore system and functionalizable surfaces. Immobilization on these materials enhances enzyme stability, activity and resistance towards harsh environmental conditions such as temperature and pH. The present study deals with synthesis of mesoporous materials namely MCM-41. For that purpose, the MCM-41 was synthesized using cetyltrimethylammonium bromide (CTAB) as a template and extractable silica from rice husk ash as a silica source. The synthesis was performed under alkaline conditions to produce white fine solid particles, followed by grafting with 3-aminopropyltriethoxysilane and activation with carbodiimide before it was immobilized with lipase. Characterization of those fine particles using Nitrogen physisorption gives BET surface area, as BET, and the pore diameterto be 1184 m²/g and 2.58 nm respectively. Fourier Transform Infrared spectra show peak of SiO2, NH2 and COOH functional group which confirms the existence of those compounds in covalent bonding formation between amine-grafted MCM-41 and lipase enzyme. Immobilized enzyme shows an increase in pH stability when compared to free enzyme at fixed temperature of 20°C in time range from 30 to 180 minutes.


2017 ◽  
Vol 11 (5) ◽  
pp. 47 ◽  
Author(s):  
Heman A. Smail ◽  
Kafia M. Shareef ◽  
Zainab H. Ramli

The adsorption of lead (Pb II) ion on different types of synthesized zeolite was investigated. The BET surface area, total pore volume & average pore size distribution of these synthesized zeolites were determined by adsorption isotherms for N2, the surface area & total pore volume of their sources were found by adsorption isothermN2.The adsorption equilibrium was measured after 24h at room temperature (RT) & concentration 10mg.L-1 of Pb (II) was used. The adsorption of heavy metal Pb (II) on four different prepared zeolites (LTA from Montmorillonite clay, FAU(Y)-B.H (G2) from Barley husk, Mordenite (G1) from Chert rock, FAU(X)-S.C (G3) from shale clay & modified Shale clay by oxalic acid (N1) & sodium hydroxide (N2)), were compared with the adsorption of their sources by using static batch experimental method. The major factors affecting the heavy metal ion sorption on different synthesized zeolites & their sources were investigated. The adsorption equilibrium capacity (Qm) of Pb (II) ion for different synthesized zeolites ordered from (N1>N2>LTA>G3>G2>G1&for their sources ordered Shale clay >Montmorilonite> Barley husk>Chert rock. The atomic absorption spectrometry was used for analysis of lead heavy metal ion, the obtained results in this study showed that the different synthesized zeolites were efficient ion exchanges for removing heavy metal, in particular, the modified zeolite from shale clay by oxalic acid.


2020 ◽  
Vol 56 (49) ◽  
pp. 6715-6718 ◽  
Author(s):  
Zi-Jian Li ◽  
Yu Ju ◽  
Bowen Yu ◽  
Xiaoling Wu ◽  
Huangjie Lu ◽  
...  

Isoreticular expansion of Th-MOFs via modulated synthesis yielded seven hierarchical complexes with superior quality single crystals, record high void space and BET surface area among Th materials, and exceptional iodine adsorption capacities.


1997 ◽  
Vol 15 (6) ◽  
pp. 465-476 ◽  
Author(s):  
G.A. El-Shobaky ◽  
A.M. Ghozza ◽  
G.M. Mohamed

Two samples of Cr2O3/Al2O3 were prepared by mixing a known mass of finely powdered Al(OH)3 with a calculated amount of CrO3 solid followed by drying at 120°C and calcination at 400°C. The amounts of chromium oxide employed were 5.66 and 20 mol% Cr2O3, respectively. The calcined solid specimens were then treated with different doses of γ-rays (20–160 Mrad). The surface and catalytic properties of the different irradiated solids were investigated using nitrogen adsorption at −196°C and the catalysis of CO oxidation by O2 at 300–400°C. The results revealed that γ-rays brought about a slight decrease in the BET surface area, SBET (15%), and in the total pore volume, Vp (20%), of the adsorbent containing 5.66 mol% Cr2O3. The same treatment increased the total pore volume, Vp (36%), and the mean pore radius, r̄ (43%), of the other adsorbent sample without changing its BET surface area. The catalytic activities of both catalyst samples were found to increase as a function of dose, reaching a maximum value at 80–160 Mrad and 40 Mrad for the solids containing 5.66 and 20 mol% Cr2O3, respectively. The maximum increase in the catalytic activity measured at 300°C was 59% and 100% for the first and second catalyst samples, respectively. The induced effect of γ-irradiation on the catalytic activity was an increase in the concentration of catalytically active sites taking part in chemisorption and in the catalysis of CO oxidation by O2 without changing their energetic nature. This was achieved by a progressive removal of surface hydroxy groups during the irradiation process.


2018 ◽  
Vol 37 (1) ◽  
pp. 493-518 ◽  
Author(s):  
Liangwei Xu ◽  
Yang Wang ◽  
Luofu Liu ◽  
Lei Chen ◽  
Ji Chen

Thermal maturity has a considerable impact on hydrocarbon generation, mineral conversion, nanopore structure, and adsorption capacity evolution of shale, but that impact on organic-rich marine shales containing type II kerogen has been rarely subjected to explicit and quantitative characterization. This study aims to obtain information regarding the effects of thermal maturation on organic matter, mineral content, pore structure, and adsorption capacity evolution of marine shale. Mesoproterozoic Xiamaling immaturity marine oil shale with type II kerogen in Zhangjiakou of Hebei, China, was chosen for anhydrous pyrolysis to simulate the maturation process. With increasing simulation temperature, hydrocarbon generation and mineral transformation promote the formation, development, and evolution of pores in the shale. The original and simulated samples consist of closed microspores and one-end closed pores of the slit throat, all-opened wedge-shaped capillaries, and fractured or lamellar pores, which are related to the plate particles of clay. The increase in maturity can promote the formation and development of pores in the shale. Heating can also promote the accumulation, formation, and development of pores, leading to a large pore volume and surface area. The temperature increase can promote the development of pore volume and surface area of 1–10 and 40-nm diameter pores. The formation and development of pore volume and surface area of 1–10 nm diameter pores are more substantial than that of 40-nm diameter pores. The pore structure evolution of the sample can be divided into pore adjustment (T < 350°C, EqRo < 0.86%), development (350°C < T < 650°C, 0.86% < EqRo < 3.28%), and conversion or destruction stages (T > 650°C, EqRo > 3.28%). Along with the increase in maturity, the methane adsorption content decreases in the initial simulation stage, increases in the middle simulation stage, and reaches the maximum value at 650°C, after which it gradually decreases. A general evolution model is proposed by combining the nanopore structure and the adsorption capacity evolution characteristics of the oil shale.


2014 ◽  
Vol 1058 ◽  
pp. 25-29
Author(s):  
Shi Jing Lin ◽  
Wu Tong Du ◽  
Ting Ting Ding ◽  
Yu Zhao ◽  
You Zhao ◽  
...  

Flower-like Co–La oxide micro/nanomaterials have been synthesized via an ethylene-glycol-mediated process, under the condition of that the mole ratio of lanthanum nitrate (La (NO3)3·6H2O) and cobalt nitrate (Co (NO3)2·6H2O) was 1:1 (based on the amount of Co (NO3)2·6H2O 0.002 mol), the dosage of urea was 2.2 g, the dosage of tetra-butyl ammonium bromide (TBAB) was 6.0 g, with magnetic stirring heating under 170 °C for 60 minutes in the 150mL ethylene glycol, the prepared precursors of Co–La oxides have regular flower-like morphology, in addition, the amount of TBAB and urea plays a significant role on the synthesis of the precursors. The flower-like Co–La oxides micro/nanomaterials were prepared after the precursors were calcinated in the muffle furnace at 800 °C for 2 h, the morphology, crystal properties and element distribution of the products were investigated by the analysis of SEM-EDX, XRD and BET, etc. The structures of these products with regular flower-like morphology are on the micrometer scale, which are hierarchically composed of nanosized building blocks, with highly polycrystalline nature, and the Brunauer–Emmett–Teller (BET) surface area of 68.5 m2/g. Therefore, those micro/nanomaterials have been developed as promising catalytic materials for their not only keeping the high surface area of nanomaterials, but effectively inhibiting aggregation.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Guotao Zhao ◽  
Zhenxiao Zhao ◽  
Junliang Wu ◽  
Daiqi Ye

Fluorine-containing hydrophobic mesoporous material (MFS) with high surface area is successfully synthesized with hydrothermal synthesis method by using a perfluorinated surfactant SURFLON S-386 template. The adsorption properties of water vapor on the synthesized MFS are also investigated by using gravimetric method. Results show that SEM image of the MFS depicted roundish morphology with the average crystal size of 1-2 μm. The BET surface area and total pore volume of the MFS are 865.4 m2 g−1and 0.74 cm3 g−1with a narrow pore size distribution at 4.9 nm. The amount of water vapor on the MFS is about 0.41 mmol g−1at 303 K, which is only 52.6% and 55.4% of MCM-41 and SBA-15 under the similar conditions, separately. The isosteric adsorption heat of water on the MFS is gradually about 27.0–19.8 kJ mol−1, which decreases as the absorbed water vapor amount increases. The value is much smaller than that on MCM-41 and SBA-15. Therefore, the MFS shows more hydrophobic surface properties than the MCM-41 and SBA-15. It may be a kind of good candidate for adsorption of large molecule and catalyst carrier with high moisture resistance.


2013 ◽  
Vol 545 ◽  
pp. 109-114 ◽  
Author(s):  
Kitirote Wantala ◽  
Pongsert Sriprom ◽  
Nusavadee Pojananukij ◽  
Arthit Neramittagapong ◽  
Sutasinee Neramittagapong ◽  
...  

The reactive red 3 was degraded by catalytic wet oxidation process over Fe-RH-MCM-41 prepared by Direct Hydrothermal Technique (DHT) at Si/Fe molar ratio of 10 using silica from rice husk. The extended reaction conditions were studied as a function of reaction temperatures, initial H2O2 concentrations and initial pH of solutions designed by Box-Behnken design (BBD) based on Response Surface Methodology (RSM) to achieve the optimal condition and interaction of independent variables. The characterizations of catalyst were studied by XRD, BET surface area and TEM to explain the morphology of surface and to confirm the hexagonal structure. The results showed the 2theta peak can be indexed to hexagonal lattice that also confirmed by TEM result and surface area about 650 m2/g. All of independent variables showed significant on the degradation of reactive red 3 except for initial H2O2 concentration.


2014 ◽  
Vol 625 ◽  
pp. 685-689 ◽  
Author(s):  
Nurulhuda Azmi ◽  
Suzana Yusup ◽  
Khalik M. Sabil

Material characterization is a crucial step to ensure the characteristics and properties of the samples are comparable to the standard adsorbent and suitable for CO2 adsorption. The objective of this work is to characterize natural calcium based materials for CO2 adsorption which are obtained from waste cockle shells. Characterization analyses are conducted by using XRD, BET and FESEM. Material characterization indicates that raw cockle shell is made up of aragonite and needle-like structure. It is also shown that CaCO3 can be decomposed to CaO through high temperature calcination process. Through physisorption analysis, the samples are classified as mesoporous materials and it is shown that calcined cockle shell is better than raw cockle shell in term of surface area and pore volume. The results proved that calcium based materials could be successfully employed as sorbent for CO2 separation.


2019 ◽  
Vol 2 (3) ◽  
pp. 1205-1209
Author(s):  
Hasan Sayğılı

The influence of carbonization temperature (CT) on pore properties of the prepared activated carbon using lentil processing waste product (LWP) impregnated with potassium carbonate was studied. Activated carbons (ACs) were obtained by impregnation with 3:1 ratio (w/w) K2CO3/LWP under different carbonization temperatures at 600, 700, 800 and 900 oC for 1h. Activation at low temperature represented that micropores were developed first and then mesoporosity developed, enhanced up to 800 oC and then started to decrease due to possible shrinking of pores. The optimum temperature for LWP was found to be around 800 oC on the basis of total pore volume and the Brunauer-Emmett-Teller (BET) surface area. The optimum LWPAC sample was found with a CT of 800 oC, which gives the highest BET surface area and pore volume of 1875 m2/g and 0.995 cm3/g, respectively.


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