scholarly journals Distribution of Iron on FCC Catalyst and Its Effect on Catalyst Performance

2021 ◽  
Vol 9 ◽  
Author(s):  
Yitao Liao ◽  
Tao Liu ◽  
Xiaohui Du ◽  
Xionghou Gao
Keyword(s):  
Surface Area ◽  
Pore Volume ◽  
Iron Concentration ◽  
Iron Deposition ◽  
X Ray Diffraction ◽  
Fcc Catalyst ◽  
Equilibrium Catalyst ◽  
Adsorption Desorption ◽  
Fcc Catalysts ◽  
Real State

The effects of different iron contamination content on the formation of iron nodules and the performance of FCC catalysts have been studied by cyclic deactivation treatment using iron naphthenate. The catalysts were characterized by X-ray diffraction, N2 adsorption-desorption, and SEM. The catalysts’ performance was evaluated by the Advanced Cracking Evaluation device. It has been found that there will be obvious nodulation on the catalyst when the iron concentration exceeds 7,400 μg/g. With the iron deposition from 53 μg/g to 11,690 μg/g, the crystal structure of zeolite will not be destroyed by iron. The surface area and pore volume of the catalyst decreased significantly; the surface area decreased from 125.3 m2/g to 91.0 m2/g, and the pore volume decreased from 0.21 cm3/g to 0.16 cm3/g. The studies also showed that the increase of iron deposition will lead to the decrease of catalytic reaction efficiency. With the iron deposition from 53 μg/g to 11,690 μg/g, the conversion decreased by 4.83%. Under the same 78 wt.% conversion, bottoms yield and coke yield increased by 2.15% and 1.31%, while gasoline yield and LCO yield decreased by 2.59% and 2.16%, respectively. The real state of the industrial iron contaminated equilibrium catalyst can be mimicked by using the cyclic deactivation method.

scholarly journals Synthesis of micro-mesopores flowerlike γ-Al2O3 nano-architectures

2014 ◽  
Vol 79 (8) ◽  
pp. 1007-1017 ◽  
Author(s):  
Mozaffar Abdollahifar ◽  
Reza Zamani ◽  
Ehsan Beiygie ◽  
Hosain Nekouei
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Pore Volume ◽  
Total Pore Volume ◽  
High Specific Surface Area ◽  
X Ray Diffraction ◽  
N2 Adsorption ◽  
X Ray ◽  
Adsorption Desorption

The micro-mesopores flowerlike ?-Al2O3 nano-architectures have been synthesized by thermal decomposition method using the synthesized AlOOH (boehmite) as precursor. After calcination at 500?C for 5 h, the obtained flowerlike ?-Al2O3 has similar structure like the AlOOH precursor. X-ray diffraction (XRD), FTIR, TG, FESEM and TEM techniques were used to characterize morphology and structure of the synthesized samples. The specific surface area (BET), pore volume and pore-size distribution of the products were determined by N2 adsorption-desorption measurements. The flowerlike ?-Al2O3 showed BET high specific surface area 148 m2 g-1 with total pore volume 0.59 cm3 g-1.

scholarly journals A Comparison of Laboratory Simulation Methods of Iron Contamination for FCC Catalysts

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 104
Author(s):  
Yitao Liao ◽  
Tao Liu ◽  
Huihui Zhao ◽  
Xionghou Gao
Keyword(s):  
Surface Structure ◽  
Laboratory Simulation ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Iron Contamination ◽  
Equilibrium Catalyst ◽  
Adsorption Desorption ◽  
Fcc Catalysts ◽  
Nodule Morphology

Two different methods of simulating iron contamination in a laboratory were studied. The catalysts were characterized using X-ray diffraction, N2 adsorption–desorption, and SEM-EDS. The catalyst performance was evaluated using an advanced cracking evaluation device. It was found that iron was evenly distributed in the catalyst prepared using the Mitchell impregnation method and no obvious iron nodules were found on the surface of the catalyst. Iron on the impregnated catalyst led to a strong dehydrogenation capacity and a slight decrease in the conversion and bottoms selectivity. The studies also showed that iron was mainly in the range of 1–5 μm from the edge of the catalyst prepared using the cycle deactivation method. Iron nodules could be easily observed on the surface of the catalyst. The retention of the surface structure in the alumina-rich areas and the collapse of the surface structure in the silica-rich areas resulted in a continuous nodule morphology, which was similar to the highly iron-contaminated equilibrium catalyst. Iron nodules on the cyclic-deactivated catalyst led to a significant decrease in conversion, an extremely high bottoms yield, and a small increase in the dehydrogenation capacity. The nodules and distribution of iron on the equilibrium catalyst could be better simulated by using the cyclic deactivation method.

Changes in kaolinite, vermiculite, and smectite clays after adsorption by hydroxy-chromium species

Soil Research ◽  
1998 ◽  
Vol 36 (3) ◽  
pp. 423 ◽  
Author(s):  
Cristina Volzone
Keyword(s):  
Surface Area ◽  
Nitrate Solution ◽  
Basal Spacing ◽  
X Ray Diffraction ◽  
Octahedral Sheet ◽  
Chromium Species ◽  
X Ray ◽  
Micropore Surface Area ◽  
Smectite Clays ◽  
Adsorption Desorption

Kaolinite, vermiculite, and montmorillonites were treated with solutions containing hydroxy-chromium (OH-Cr) species. The OH-Cr solution was prepared by adding 0·2 М NaOH to 0·1 М chromium nitrate solution and allowing the solution to stand at 60°C for 1 day. The samples were characterised by chemical analyses, N2 adsorption-desorption isotherms, and X-ray diffraction. The textural and structural behaviours of kaolinite, vermiculite, and the montmorillonites were analysed in the original samples and after treatment with the polymeric OH-Cr species. The montmorillonites showed higher retention of chromium (19·20%), higher basal spacing (2·06 nm), and higher micropore surface area (276 m2/g) than the vermiculite (3·70%, 1·49 nm, 13 m2/g) and kaolinite (1·15%, 0·73 nm, ~1 m2/g) clays after treatment with the OH-Cr species. In contrast, the external surface area increased from 6 to 9 m2/g for kaolinite and from 18 to 24 m2/g for vermiculite, and decreased from 7 to 4 m2/g for montmorillonite after treatment with the OH-Cr solution. The residual chromium, basal spacing, and texture of the clays after treatment with the OH-Cr species were primarily related to the magnitude of the negative charge originating from the octahedral sheet.

scholarly journals The Internal Recycle Reactor Enhances Porous Calcium Silicate Hydrates to Recover Phosphorus from Aqueous Solutions

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Wei Guan ◽  
Shichao Tian
Keyword(s):  
Surface Area ◽  
Pore Volume ◽  
Calcium Silicate ◽  
Ph Value ◽  
Optimal Operation ◽  
Phosphorus Recovery ◽  
Operation Conditions ◽  
Calcium Silicate Hydrates ◽  
Recycle Reactor ◽  
Adsorption Desorption

In this experiment, the porous calcium silicate hydrates (P-CSHs) were prepared via a hydrothermal method and then modified by polyethylene glycol (PEG). The modified P-CSHs combined with an internal recycle reactor could successfully recover the phosphorus from electroplating wastewater. The modified P-CSHs were characterized by X-ray diffraction (XRD), N2 adsorption-desorption isotherms, and Fourier transform infrared spectroscopy (FT-IR). After compared with different samples, the modified P-CSHs-PEG2000 sample had larger specific surface area of 87.48 m2/g and higher pore volume of 0.33 cm3/g, indicating a high capacity for phosphorus recovery. In the process of phosphorus recovery, the pH value of solution was increased to 9.5, which would enhance the recovery efficiency of phosphorus. The dissolution rate of Ca2+ from P-CSH-PEG2000 was fast, which was favorable for phosphorus precipitation and phosphorus recovery. The effects of initial concentration of phosphorus, P-CSHs-PEG2000 dosage, and stirring speed on phosphorus recovery were analyzed, so the optimal operation conditions for phosphorus recovery were obtained. The deposition was analyzed by XRD, N2 adsorption-desorption, and SEM techniques; it was indicated that the pore volume and surface area of the P-CSHs-PEG2000 were significantly reduced, and the deposition on the surface of P-CSHs-PEG2000 was hydroxyapatite.

Acid and aluminium modification of sepiolite and its application in FCC catalysis

Clay Minerals ◽  
2010 ◽  
Vol 45 (1) ◽  
pp. 15-22 ◽  
Author(s):  
Shu-Qin Zheng ◽  
Yong Han ◽  
Xiao-Hong Huang ◽  
Ya-Li Dai ◽  
Dong Qian ◽  
...  
Keyword(s):  
Pore Volume ◽  
Treatment Time ◽  
Treatment Temperature ◽  
Fluid Catalytic Cracking ◽  
Ion Concentration ◽  
X Ray Diffraction ◽  
Salt Treatment ◽  
Excellent Performance ◽  
X Ray ◽  
Fcc Catalysts

AbstractThe effects of acid and Al concentration, type of Al salt, treatment temperature and time of removal of Mg from sepiolite have been investigated, as has the use of modified sepiolite as an active fluid catalytic cracking (FCC) matrix. The samples were characterized by N2 adsorption and X-ray diffraction. Mg removal from sepiolite increased with increasing acid and Al ion concentration, treatment time and temperature. The temperature had the greatest impact on Mg removal. After acid and Al modification, 29% of the Mg was removed. When using the modified sepiolites as active matrices in FCC catalysts, the specific surface area, pore volume and mesoporous pore volume of the catalysts increased and they exhibited excellent performance in resisting the effects of heavy-metals as a result of the introduction of Mg oxide from the modified sepiolite.

scholarly journals Ru0·Run+/Al2O3 as a Versatile Catalyst in the Isomerization of Allyl Alcohol

2021 ◽  
Vol 9 ◽  
Author(s):  
Julián Enciso ◽  
Alfonso Ramírez ◽  
Carlos Ostos ◽  
Adriana Echavarría ◽  
Misael Córdoba ◽  
...  
Keyword(s):  
Surface Area ◽  
Heterogeneous Catalyst ◽  
Pore Volume ◽  
Allyl Alcohol ◽  
Active Species ◽  
X Ray Diffraction ◽  
X Ray ◽  
Isomerization Product ◽  
Redox Sites ◽  
Alcohol Conversion

This study focuses on examining the isomerization of allyl alcohol using ruthenium (Ru) supported on alumina as a heterogeneous catalyst. The synthesized Ru/Al solids were characterized by various characterization techniques. The content of Ru was estimated by the energy dispersive x-ray technique. The x-ray diffraction (XRD) confirmed the presence of phases in the support and active species in the catalysts. The surface area of the support after Ru impregnation and the pore volume were determined by nitrogen physisorption. The analysis of programmed temperature (TPR and TPO) shows different redox sites which is confirmed by XPS. The catalytic results suggest a dependence on the amount of available metallic Ru, as well as the importance of the continuous regeneration of the metal using H2 to achieve a good conversion of the allyl alcohol. For comparison purposes, the commercial Ru on alumina 5% (CAS 908142) was used. The results show up to 68% alcohol conversion and 27% yield of the isomerization product using Ru(1,5.4h)/Al catalyst in comparison with 86% conversion and 39% yield of the isomerization product using CAS 908142. In contrast, our catalysts always presented higher TOF values (149–160) in comparison with CAS 908142 (101).

A Facile Template Approach for Preparing Microstructures of Bimodal Crystalline Mesoporous Titania Powders

2012 ◽  
Vol 616-618 ◽  
pp. 1797-1800
Author(s):  
Yu Mei Gong ◽  
Qing Liang ◽  
Jing Chuan Song ◽  
Ling Ming Xia
Keyword(s):  
Electron Microscope ◽  
Surface Area ◽  
Nitrogen Adsorption ◽  
Mesoporous Titania ◽  
Mass Ratio ◽  
X Ray Diffraction ◽  
Average Pore ◽  
X Ray ◽  
Transmission Electron ◽  
Adsorption Desorption

This paper presents the preparation of bimodal crystalline macro-/mesoporous titania powders by using a pluronic polymer (EO20PO70EO20, P123) as a template through a hydrothermal treatment. The as-prepared powders were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, scanning electron microscope (SEM) and transmission electron microscope (TEM). The results reveal that the amount of P123 has a significant effect on the surface area of the mesoporous titania. When the mass ratio of P123:TBOT is 1:14, the crystalline macro-/mesoporous titania has the largest surface area (120.96 m2/g), the average pore diameter of this sample reaches a minimum of 6.67 nm.

CuO/CeO2 and CuO/PrO2-CeO2 Catalysts for Preferential Oxidation of CO

2013 ◽  
Vol 773 ◽  
pp. 601-605 ◽  
Author(s):  
Zhi Jun Zhao ◽  
Ruo Yu Wang ◽  
Qian Long Zhao ◽  
En Peng Wang ◽  
Hai Quan Su ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Hydrothermal Method ◽  
Surface Area ◽  
Pore Volume ◽  
Crucial Role ◽  
Textural Properties ◽  
Bet Surface Area ◽  
Oxidation Of Co ◽  
Preferential Oxidation Of Co ◽  
Adsorption Desorption

The CuO/CeO2and CuO/PrO2-CeO2catalysts were prepared by the hydrothermal method, and characterized via XRD, SEM and N2adsorption-desorption techniques. The study shows that the BET surface area and pore volume of the CuO/PrO2-CeO2catalysts increase with the increase of praseodymium content. The CuO/CeO2catalyst presents higher catalytic activity in compare with the CuO/PrO2-CeO2catalysts although the addition of praseodymium promotes textural properties of the CuO/CeO2catalysts, and it proves that the interaction of CuO and CeO2has a crucial role in CO-PROX.

Synthesis, Characterization and Physiochemical Properties of Platinum Supported on Mesoporous Carbon

2011 ◽  
Author(s):  
Salam J. J. Titinchi ◽  
Waheed Saban ◽  
Leslie Petrik ◽  
Hanna S. Abbo
Keyword(s):  
Surface Area ◽  
Pore Volume ◽  
Mesoporous Carbon ◽  
Chemical Vapour ◽  
Nitrogen Adsorption ◽  
Ordered Mesoporous Carbon ◽  
Pt Catalyst ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ordered Mesoporous

Ordered mesoporous carbon (OMC) has been prepared by impregnating the pores of the silica template (SBA-15) with liquid petroleum gas (LPG) or sucrose. The desired support (OMC) was obtained after dissolution with NaOH. Platinum nanoparticles were dispersed on ordered mesoporous carbons using Chemical Vapour Deposition (CVD) method and Pt(acac)2 as metal source. The resulting ordered mesoporous carbon possess a large surface area with high microporosity, and a controlled pore size distribution, High-quality carbon replicas of SBA-15 show an X-ray diffraction peak at low angle, which indicates that the structural periodicity of the (111) planes has been maintained. Their pore volume and specific surface area are high and the pore volume is almost entirely microporous. The synthesized Pt/OMC was characterized by powder X-Ray diffraction, HR-TEM, HR-SEM, EDS, thermogravimetric analysis, and nitrogen adsorption. The performance of Pt catalyst supported OMC was evaluated by electrochemical studies, which shows almost similar activity to the commercial catalyst.

scholarly journals Preparation of Terminalia catappa Shell Based Activated Carbon by Microwave Assisted Chemical Activation

2019 ◽  
Vol 1 (1) ◽  
pp. 54-60
Author(s):  
Awitdrus Awitdrus
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Chemical Activation ◽  
Bet Surface Area ◽  
Koh Activation ◽  
X Ray Diffraction ◽  
Scanning Microscope ◽  
Terminalia Catappa ◽  
Electron Scanning Microscope ◽  
Adsorption Desorption

Activated carbon was prepared from Terminalia catappa shells using microwave asissted KOH activation. The ratio of mass percentages of Terminalia catappa and KOH were 4:1, 4:2, and 4:3. Terminalia catappa based activated carbon was prepared by KOH activation at the room temperature for 24 hours and followed by microwave irradiation at the out put power of 630 Watt for 20 minutes. The physical properties of activated carbon i.e. surface morphology, micro structure, and BET surface area were characterized by electron scanning microscope, X-ray diffraction and N2 adsorption-desorption isotherm at 77K, respectively. The highest BET surface area was 312 m2/g with adsorption of activated carbon towards methylene blue by 84.4 mg/g. The BET surface area was directly correlated with the stack height (Lc) of the activated carbon.

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