coke deposited on catalyst

Catalyst regeneration using CO2 as reactant through

The possibility of CO 2 recycling into standard refinery can largely mitigate greenhouse gas emissions. It was previously demonstrated that alumina modified by either potassium or lithium in the presence of vanadium was able to promote the reaction of CO 2 with coke in the presence of O 2 during the regeneration step of a spent catalyst. Herein, vanadium‐sodium and vanadium‐calcium on Get price

Coke deposition detection through the analysis of catalyst

Coke deposition on catalyst will not only reduce catalytic activity and selectivity, but also affect the product yield, the reaction residence time, the regenerator temperature and so on. As a result, it is necessary to measure the amount of coke deposition on catalyst. This paper proposes a new method based on image analysis. An image acquisition system consisting of a flatbed scanner and an Get price

COKE FORMATION ON SILICA

The mechanism of coke formation on silica-alumina cracking catalysts was studied by analysis of cracking experiments with seven pure hydrocarbons at 445' C. and n-hexadecane at 500 C. under a variety of process conditions. Coke deposits were isolated from selected catalyst samples for infrared spectral examination. Get price

Coking and Activity of Solid Acid Alkylation Catalysts in

Jul 17, 2020The deactivation is due to the formation of 'coke' deposits (low-volatile hydrocarbonaceous substance) that plug up the micropores and block the active sites. The problem of catalyst coking is also prevalent in other industrial processes such as Get price

Development of a New Detection Method for TPO Analysis of

For these experiments, approximately 20mg of coked catalyst were loaded in the sample cell. A helium carrier containing a low concentration of oxygen flowed over the sample at a flow rate of 20-80 cc/min. The temperature was increased linearly from room temperature until the oxidation of all carbon deposits Get price

Capturing Coke Precursors in a Pd Lattice: A Carbon

Herein, we report a technique that significantly decreases coke formation by capturing coke precursors in a Pd lattice. The Pd‐added H 3 PW 12 O 40 /C catalyst (Pd‐PWC) showed stable catalytic activity and the amount of deposited coke formed was decreased to about 40 % of that without Pd addition. Get price

Properties Analysis of Spent Catalyst for Fixed

The influences of deposited coke and metals on con-figuration deactivation are various because deposition positions of coke and metals on catalyst are different. It is an important method to study the deactivation reasons of residue hydrotreating catalyst by researching deposition state and distribution of coke and metals on catalyst. It has Get price

(178b) Catalytic Cracking of Dodecane in Supercritical

In addition to liquid phase analysis, we characterized the coke deposited on the catalyst using Temperature Programmed Oxidation (TPO) technique. Water reduces coke formation by an order of magnitude and alters its chemical characteristics. Coke deposited in the presence of water is mostly soft coke while coke formed in the absence of water is Get price

Things go better with coke: the beneficial role of

Carbonaceous or hydrocarbonaceous deposits formed on the surface of heterogeneous catalysts during reaction are typically associated with catalyst deactivation through coking. However, there are a number of cases where such deposits may enhance catalytic performance. This includes: coke deposits acting direc 2016 most accessed Catalysis Science and Technology articles Get price

In

A coke removal system removes coke deposit from the walls of a high temperature passage in which hydrocarbon fuel is present. The system includes a carbon-steam gasification catalyst and a water source. The carbon-steam gasification catalyst is applied to the walls of the high temperature passage. Get price

Structure and composition of hard coke deposited on

Sep 10, 2013Carbonaceous deposits (hard coke) were studied by various solid state 13 C nuclear magnetic resonance (NMR) techniques after demineralization of the spent and regenerated fluid catalytic cracking (FCC) catalysts obtained from Indian refineries. A number of structural parameters such as aromaticity, H/C ratio, fraction of protonated ( f a P) and non-protonated ( f a NP) aromatic carbons, Get price

Fluid catalytic cracking is an important step in producing

Carbon is deposited on the catalyst during the cracking process. This carbon, known as catalyst coke, adheres to the catalyst, reducing its ability to crack the oil. The coke on the spent catalyst is burned off, which reheats the catalyst to add heat to the FCC process. Regeneration produces a flue gas that passes through environmental control Get price

Regeneration of deactivated zeolite catalysts by

There are many possible causes for this deactivation, one of them is the formation of coke deposits on the catalyst. Those deposits can diminish the activity of the catalyst either by blocking the pores of the catalyst or by poisoning the active sites. There are several possibilities to recover catalyst activity by removing the coke deposits. Get price

Location of coke in ZSM

carbonaceous deposits (coke) on their surface. Hence, they could be utilized only in those processes (like the FCC) wherein the catalyst is continuously regenerated or in those (like hydrocracking) where very high partial pressures of hydrogen restrict the rate of coke formation. The ZSM-S zeolites are not Get price

Development of a New Detection Method for TPO Analysis of

For these experiments, approximately 20mg of coked catalyst were loaded in the sample cell. A helium carrier containing a low concentration of oxygen flowed over the sample at a flow rate of 20-80 cc/min. The temperature was increased linearly from room temperature until the oxidation of all carbon deposits Get price

Probability of Chain Growth in Coke Formation on Metals

The mixed coke over catalyst was separated by sieving to Pt-based catalyst and Al2O3 for coke characterization. 2. Analytical Methods IR was used to characterize the structural properties of carbon-aceous deposit by the lattice vibration. The vibration bands between 400-4,000cm−1 can indicate the structural framework of coke. The Get price

Utilization of waste spent hydroprocessing catalyst

de-coked catalyst is shown in Table 1. The deposited species changes noticeably the specific surface area (SSA) and total pore volume (TPV) of the spent catalyst (Table 1). The decrease in SSA and TPV values indicated that the catalyst is deactivated by pore blockage as well as fouling of the active sites by coke and metal deposits. Get price

Location of coke in ZSM

carbonaceous deposits (coke) on their surface. Hence, they could be utilized only in those processes (like the FCC) wherein the catalyst is continuously regenerated or in those (like hydrocracking) where very high partial pressures of hydrogen restrict the rate of coke formation. The ZSM-S zeolites are not Get price

Life and death of a single catalytic cracking particle

Tramp Fe particles are deposited on the surface of the FCC catalyst particle because they are too large to enter the particle through pores and can form highly localized nodules rich in Fe . so that most of the coke was already removed from the catalyst. Typically, a few tenths of a wt % of coke are still present on the ECat, which was Get price

Discerning the Location and Nature of Coke Deposition from

The formation of carbonaceous deposits (coke) in zeolite pores during catalysis leads to temporary deactivation of catalyst, necessitating regeneration steps, affecting throughput, and resulting in partial permanent loss of catalytic efficiency. Yet, even to date, the coke molecule distribution is quite Get price

Heterogeneous Catalysis A Radical Twist to the Versatile

2 generation and formation of coke deposits). However, in recent announcements, companies like Siluria and UOP report on the (pre)-commercialization of methane coupling routes to ethylene.[6] In a recent study, Guo and co-workers reported on a new catalyst material, which could circumvent the disadvantages of, for example, OCM technology.[7] Get price

Burning the coke deposited on the catalyst particles

Burning the coke deposited on the catalyst particles generates all the heat necessary for catalytic cracking. Therefore, the coke burning rate is a critical parameter to control the rate of cracking. The composition of dry flue gas from the regenerator of an FCC unit is given in vol% as follows: Gas Volume % N2 81.6 CO2 15.7 CO 1.5 O2 1.2 Get price