scholarly journals Photo-spectroscopy of mixtures of catalyst particles reveals their age and type

2016 ◽  
Vol 188 ◽  
pp. 69-79 ◽  
Author(s):  
M. M. Kerssens ◽  
A. Wilbers ◽  
J. Kramer ◽  
P. de Peinder ◽  
G. Mesu ◽  
...  

Within a fluid catalytic cracking (FCC) unit, a mixture of catalyst particles that consist of either zeolite Y (FCC-Y) or ZSM-5 (FCC-ZSM-5) is used in order to boost the propylene yield when processing crude oil fractions. Mixtures of differently aged FCC-Y and FCC-ZSM-5 particles circulating in the FCC unit, the so-called equilibrium catalyst (Ecat), are routinely studied to monitor the overall efficiency of the FCC process. In this study, the age of individual catalyst particles is evaluated based upon photographs after selective staining with substituted styrene molecules. The observed color changes are linked to physical properties, such as the micropore volume and catalytic cracking activity data. Furthermore, it has been possible to determine the relative amount of FCC-Y and FCC-ZSM-5 in an artificial series of physical mixtures as well as in an Ecat sample with unknown composition. As a result, a new practical tool is introduced in the field of zeolite catalysis to evaluate FCC catalyst performances on the basis of photo-spectroscopic measurements with an off-the-shelf digital single lens reflex (DSLR) photo-camera with a macro lens. The results also demonstrate that there is an interesting time and cost trade-off between single catalyst particle studies, as performed with e.g. UV-vis, synchrotron-based IR and fluorescence micro-spectroscopy, and many catalyst particle photo-spectroscopy studies, making use of a relatively simple DSLR photo-camera. The latter approach offers clear prospects for the quality control of e.g. FCC catalyst manufacturing plants.

Author(s):  
Clifford S. Rainey

The spatial distribution of V and Ni deposited within fluidized catalytic cracking (FCC) catalyst is studied because these metals contribute to catalyst deactivation. Y zeolite in FCC microspheres are high SiO2 aluminosilicates with molecular-sized channels that contain a mixture of lanthanoids. They must withstand high regeneration temperatures and retain acid sites needed for cracking of hydrocarbons, a process essential for efficient gasoline production. Zeolite in combination with V to form vanadates, or less diffusion in the channels due to coke formation, may deactivate catalyst. Other factors such as metal "skins", microsphere sintering, and attrition may also be involved. SEM of FCC fracture surfaces, AEM of Y zeolite, and electron microscopy of this work are developed to better understand and minimize catalyst deactivation.


2012 ◽  
Vol 18 (S5) ◽  
pp. 75-76
Author(s):  
C. Costa ◽  
P. Marques ◽  
P. A. Carvalho

The most active phase of the fluid catalytic cracking (FCC) catalyst, used in oil refinery, is zeolite-Y which is an aluminosilicate with a high internal and external surface area responsible for its high reactivity. Waste FCC catalyst is potentially able to be reused in cement-based materials - as an additive - undergoing a pozzolanic reaction with calcium hydroxide (Ca(OH)2) formed during cement hydration. This reaction produces additional strength-providing reaction products i.e., calcium silicate hydrate (C-S-H) and hydrous calcium aluminates (C-A-H) which exact chemical formula and structure are still unknown. Partial replacement of cement by waste FCC catalyst has two key advantages: (1) lowering of cement production with the associated pollution reduction as this industry represents one of the largest sources of man-made CO2 emissions, and (2) improving the mechanical properties and durability of cement-based materials. Despite these advantages, there is a lack of fundamental knowledge on pozzolanic reaction mechanisms as well as spatial distribution of porosity and solid phases interactions at the microstructural level and consequently their relationship with macroscopical engineering properties of catalyst/cement blends.


1997 ◽  
Vol 15 (4) ◽  
pp. 289-299 ◽  
Author(s):  
Ivar M. Dahl ◽  
Elisabeth Myhrvold ◽  
Åse Slagtern ◽  
Michael Stöcker

Two dealuminated β-zeolites, zeolite Y and MCM-22 as well as silicalite, MCM-41 and AlPO4-5 have been studied as hydrophobic adsorbents in water solutions. Dealuminated β-zeolite, MCM-22 and silicalite all adsorb alcohols from water solutions. Enhanced adsorption is obtained for alcohols with longer alkyl chains. Adsorption in the practically most interesting 10–80% range of zeolite filling may adequately be described by Langmuir isotherms. The Langmuir adsorption constants are similar for β-zeolite, MCM-22 and silicalite. This indicates that the adsorption is independent of the pore structure for the alcohols tested in this study. The surface silanol density is however important, such that a low SiOH density is required to give lipophilic properties. In line with this, dealuminated zeolite Y, as prepared here, and MCM-41 give only a poor preference for alcohols from water. For the β-zeolite, the dealumination procedure is important for retaining the micropore volume and adsorption capacity of the zeolite. AlPO4-5 shows no potential as an adsorbent for alcohols from water solutions.


Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1385
Author(s):  
Botagoz Zhuman ◽  
Shaheen Fatima Anis ◽  
Saepurahman ◽  
Gnanapragasam Singravel ◽  
Raed Hashaikeh

Zeolite-based catalysts are usually utilized in the form of a composite with binders, such as alumina, silica, clay, and others. However, these binders are usually known to block the accessibility of the active sites in zeolites, leading to a decreased effective surface area and agglomeration of zeolite particles. The aim of this work is to utilize carbon nanostructures (CNS) as a binding material for nano-zeolite-Y particles. The unique properties of CNS, such as its high surface area, thermal stability, and flexibility of its fibrous structure, makes it a promising material to hold and bind the nano-zeolite particles, yet with a contemporaneous accessibility of the reactants to the porous zeolite structure. In the current study, a nano-zeolite-Y/CNS composite catalyst was fabricated through a ball milling approach. The catalyst possesses a high surface area of 834 m2/g, which is significantly higher than the conventional commercial cracking catalysts. Using CNS as a binding material provided homogeneous distribution of the zeolite nanoparticles with high accessibility to the active sites and good mechanical stability. In addition, CNS was found to be an effective binding material for nano-zeolite particles, solving their major drawback of agglomeration. The nano-zeolite-Y/CNS composite showed 80% conversion for hexadecane catalytic cracking into valuable olefins and hydrogen gas, which was 14% higher compared to that of pure nano-zeolite-Y particles.


2019 ◽  
Vol 9 (24) ◽  
pp. 6977-6992 ◽  
Author(s):  
Qandeel Almas ◽  
Muhammad Awais Naeem ◽  
Maria Auxiliadora S. Baldanza ◽  
Jessica Solomon ◽  
Jeffery C. Kenvin ◽  
...  

Transformations of an industrial zeolite-based fluid catalytic cracking (FCC) catalyst and its coke deposits during regeneration following FCC reactions of a representative refinery stream are investigated.


2013 ◽  
Vol 1 ◽  
pp. 194308921350702
Author(s):  
Madhavi Madeti ◽  
Sharad V. Lande ◽  
Kalpana G ◽  
R. K. Mewada ◽  
R. V. Jasra

We have attempted a green alternative to reuse the spent fluid catalytic cracking (FCC) catalyst that is used in petroleum refining industry for the upgradation and purification of various petroleum streams and residues. The spent FCC zeolite–based catalyst modified by enhancing the acidic properties by incorporating Zn and In metals in the matrix. The various prepared catalysts were systematically characterized by X-ray powder diffraction and Brunauer–Emmett–Teller (BET; adsorption isotherm) surface area. The acidity of the materials was studied by temperature-programmed desorption of ammonia (NH3-TPD). The well-characterized catalysts were applied for liquid phase benzylation of o-xylene using benzyl chloride.


2017 ◽  
Vol 161 ◽  
pp. 23-32 ◽  
Author(s):  
Abdelrahman I. Hussain ◽  
Arudra Palani ◽  
Abdullah M. Aitani ◽  
Jiří Čejka ◽  
Mariya Shamzhy ◽  
...  

2020 ◽  
Vol 26 (52) ◽  
pp. 11995-12009 ◽  
Author(s):  
Marjolein E. Z. Velthoen ◽  
Alessandra Lucini Paioni ◽  
Iris E. Teune ◽  
Marc Baldus ◽  
Bert M. Weckhuysen

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