Alkylation reactions over ion-exchanged molecular sieve zeolite catalysts. Part 2.—Alkylation of toluene with methanol: consideration of the effects of catalyst deactivation on the primary product distribution

1983 ◽  
Vol 79 (2) ◽  
pp. 297 ◽  
Author(s):  
Brendan Coughlan ◽  
William M. Carroll ◽  
John Nunan
Keyword(s):  
Molecular Sieve ◽  
Catalyst Deactivation ◽  
Product Distribution ◽  
Zeolite Catalysts ◽  
Alkylation Reactions ◽  
Primary Product Distribution

Kinetic Study of the Simultaneous Cracking of Paraffins and Methanol on HZSM-5 Zeolite Catalysts

2007 ◽  
Vol 5 (1) ◽  
Author(s):  
Diana Mier ◽  
Andrés Tomás Aguayo ◽  
Alaitz Atutxa ◽  
Ana G Gayubo ◽  
Javier Bilbao
Keyword(s):  
Kinetic Model ◽  
Catalyst Deactivation ◽  
Fixed Bed ◽  
Acid Catalyst ◽  
Product Distribution ◽  
Operating Conditions ◽  
Zeolite Catalysts ◽  
Fixed Bed Reactor ◽  
Light Olefins ◽  
Feed Temperature

A study has been carried out on the effect of acid catalyst properties and operating conditions (methanol/n-butane ratio in the feed, temperature, space time, time on stream) on the yield of light olefins (C2-C4) in the simultaneous cracking of n-butane and methanol. The operation has been carried out in an isothermal fixed bed reactor in the 400-575 °C range, using catalysts prepared based on HZSM-5 zeolites (with different Si/Al ratio), HY, Ni/HZSM-5 and SAPO-18. The results are evidence of a synergism between the transformation reactions of both reactants, whose consequence is an increase in the yield of olefins that correspond to the transformation of methanol and the cracking of n-butane. Furthermore, catalyst deactivation by coke is significantly attenuated compared to the corresponding transformation of methanol. Based on the effect of operating conditions on product distribution, a kinetic model is proposed by combining the schemes corresponding to the transformation of individual components.

scholarly journals Study on the hydrothermal liquefaction of antibiotic residues with molecular sieve catalysts in the ethanol–water system: focus on product distribution and characterization

RSC Advances ◽  
2021 ◽  
Vol 11 (43) ◽  
pp. 26763-26772
Author(s):  
Jian Yang ◽  
Chen Hong ◽  
Yi Xing ◽  
Zixuan Zheng ◽  
Zaixing Li ◽  
...  
Keyword(s):  
Molecular Sieve ◽  
Water System ◽  
Product Distribution ◽  
Hydrothermal Liquefaction ◽  
Raw Material ◽  
Antibiotic Residues ◽  
Bio Oil ◽  
Antibiotic Residue ◽  
System Focus

In this study, the antibiotic residue was used as a raw material to catalyze hydrothermal liquefaction (HTL) in an ethanol–water system to prepare bio-oil.

Para-directed aromatic reactions over shape-selective molecular sieve zeolite catalysts

1979 ◽  
Vol 101 (22) ◽  
pp. 6783-6784 ◽  
Author(s):  
N. Y. Chen ◽  
W. W. Kaeding ◽  
F. G. Dwyer
Keyword(s):  
Molecular Sieve ◽  
Zeolite Catalysts ◽  
Shape Selective

Optimization of Vapor Phase Pyridine Synthesis Hindered by Rapid Catalyst Deactivation

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Suresh Kumar Reddy Kuppi Reddy ◽  
Inkollu Sreedhar ◽  
Kondapuram Vijaya Raghavan ◽  
Shivanand Janardan Kulkarni ◽  
Machiraju Ramakrishna
Keyword(s):  
Catalyst Deactivation ◽  
A Priori ◽  
Coke Formation ◽  
Product Distribution ◽  
Combined Effects ◽  
Reactor Operation ◽  
Proper Selection ◽  
Pyridine Bases ◽  
Deactivation Process ◽  
Selection Of

The synthesis of pyridine bases from acetaldehyde, formaldehyde and ammonia through aminocyclization continues to provide the best prospect for meeting growing demand. A proper selection of catalyst and standardization of process parameters are vital to achieve a market friendly product distribution and reactor operation. In this work, the major responsible factors for enhancing the activity and selectivity of HZS-5 catalysts have been identified and their individual and combined effects on aldehyde conversion, coke formation and selectivity to pyridine formation have been assessed. A priori assessment of catalyst time on stream behavior has been achieved by modeling the catalyst deactivation process.

Effect of Silica Base Catalyst on Transformation of Methanol to Hydrocarbon

2017 ◽  
Vol 751 ◽  
pp. 512-517 ◽  
Author(s):  
Supranee Lao-Ubol ◽  
Phunthinee Somwongsa ◽  
Pracha Laoauyporn ◽  
Pasinee Panith ◽  
Siriporn Larpkiattaworn ◽  
...  
Keyword(s):  
Pore Diameter ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Liquid Hydrocarbon ◽  
Product Distribution ◽  
Catalytic Performance ◽  
Zeolite Catalysts ◽  
Fixed Bed Reactor ◽  
Phosphorus Species ◽  
Methanol To Hydrocarbon

Five different types of silica catalyst (SBA-15, SBA-15-PO3H2, and three different Si/Al ratio of commercial zeolites (30, 80 and 280) were used to study the transformation of methanol to hydrocarbon (MTH). The aim of this study was to investigate the effect of pore diameter and acidity in the structure of silica catalysts on the process performances in terms of methanol conversion and hydrocarbon selectivity. The mesoporous silica catalysts were prepared by co-condensation method. The catalysts samples were characterized by GC-MS, XRD, BET, and NH3-TPD techniques. The catalytic performance of synthesized and commercial catalysts for MTH process was evaluated using a homemade fixed bed reactor at temperature (300°C). It was found that the liquid hydrocarbon product provided by zeolite catalysts is aromatic hydrocarbons-rich. High Si/Al zeolites with larger pore size lead to higher selectivity and yield to paraffins (C1-C7). In contrast to commercial zeolite catalyst, SBA-15 and its modification with phosphorus species showed no conversion under studied condition. These results indicate that both pore diameter and acidity influence the product distribution in methanol to hydrocarbon process.

scholarly journals Product Distribution in Degradation of Polypropylene over Silica-Alumina and CaX Zeolite Catalysts

1983 ◽  
Vol 56 (9) ◽  
pp. 2768-2773 ◽  
Author(s):  
Yoshio Uemichi ◽  
Yasunori Kashiwaya ◽  
Masaya Tsukidate ◽  
Akimi Ayame ◽  
Hisao Kanoh
Keyword(s):  
Product Distribution ◽  
Zeolite Catalysts ◽  
Silica Alumina

scholarly journals Deactivation of Zeolite Catalysts in the Prins Reaction between Propene and Formaldehyde in the Liquid Phase

Catalysts ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1181
Author(s):  
Stanislav P. Bedenko ◽  
Konstantin I. Dement’ev ◽  
Valentin F. Tret’yakov
Keyword(s):  
Liquid Phase ◽  
Kinetic Model ◽  
Pore Diameter ◽  
Product Distribution ◽  
Acid Sites ◽  
Weak Acid ◽  
Zeolite Catalysts ◽  
Prins Reaction ◽  
Acidic Properties ◽  
Deactivation Process

The Prins reaction between propene and formaldehyde was studied over H-BEA, H-FAU, H-MFI and H-MOR zeolites at 150 °C in liquid phase. It was found that the H-BEA sample is the most active and selective toward buta-1,3-diene; the H-MFI is a potential catalyst for 3-buten-1-ol synthesis, while H-FAU can be used for 4-methyl-1,3-dioxane production. It had been confirmed that zeolite textural and acidic properties influence catalyst behaviour: the acidic properties influence sample activity, while product distribution is controlled by pore volume and effective pore diameter. The sample’s deactivation process had been studied and the kinetic model of deactivation was proposed. It was shown that the deactivation rate for the H-MFI catalyst is four times greater than for the H-BEA catalyst, probably because its strong/weak acid sites ratio is much more high than for the H-BEA.

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