Production of olefins via oxidative de-hydrogenation of C3‒C4 fraction by O2 over (Cr‒Mo)SiO2

Research Paper (postgraduate) , 2015 , 16 Pages

Chemistry - Organic Chemistry

The present study investigates the oxidative dehydrogenation of propane-butane (C3–C4) fraction over mono (Cr or Mo) and bi-metal (Cr-Mo) loaded SiO2 catalysts. The catalysts were prepared by sequential impregnation method at 500oC calcination temperature. Experiments were performed by feeding C3–C4 fraction, oxygen, nitrogen, and steam into a continuous flow quartz reactor at an atmospheric pressure (P = 1 atm.), reaction temperatures between 500 – 650oC, gas hourly space velocity (GHSV) within 100 – 400 h-1, and at reaction time (tr) = 2h. Appropriate water vapor addition to the feed sinificantly minimizes oxidation into coke deposits on the catalyst surface, and also prevents further olefin conversion into undesirable product. The physicochemical properties were evaluated by BET, XRD, IR, and EPR characterization techniques. The major oxidation products are ethylene, propylene, isobutylene, butylene. This paper reports that the total yield of olefins (Ʃ C2-C4) = 66.0 % was achieved at 83.5 % conversion level of C3–C4 at 630oC. The results indicate that the addition of Mo to catalysts of Cr/SiO2 modifies its catalytic activity for the ODH reaction. Mono-metallic catalysts (Cr/SiO2 and Mo/SiO2) were prepared for comparison purposes.

Inhaltsverzeichnis (Table of Contents)

• Abstract
• 1. Introduction
• 2. Experimental
• 2.1 Materials and Methods:
• 2.2 Catalysts Preparation:
• 2.3 Catalysts Treatment:
• 2.4 Catalysts Test:
• 2.5 Oxidative De-hydrogenation of C3—C4
• 3. Results and Discussion
• 3.1 Catalyst Characterization
• 3.2 Catalytic Performance
• 3.3 Effect of Reaction Temperature
• 3.4 Effect of GHSV
• 3.5 Effect of Steam Addition
• 3.6 Effect of Oxygen Partial Pressure
• 3.7 Catalyst Stability
• 4. Conclusions
• References

Zielsetzung und Themenschwerpunkte (Objectives and Key Themes)

This study investigates the oxidative dehydrogenation of propane-butane (C3-C4) fraction over mono (Cr or Mo) and bi-metal (Cr-Mo) loaded SiO2 catalysts. The main objective is to determine the optimal catalyst composition and reaction conditions for maximizing the yield of olefins (ethylene, propylene, isobutylene, and butylene) from the C3-C4 fraction. The study aims to understand the effects of different catalyst components, reaction temperature, gas hourly space velocity (GHSV), and steam addition on the catalytic activity, selectivity, and stability of the catalysts.

• Catalytic oxidative dehydrogenation of C3-C4 fraction
• Catalyst design and synthesis for enhanced olefin production
• Influence of catalyst composition (Cr, Mo, Cr-Mo) on catalytic performance
• Optimization of reaction conditions for maximizing olefin yield
• Investigation of catalyst stability and deactivation mechanisms

Zusammenfassung der Kapitel (Chapter Summaries)

The introduction provides a comprehensive overview of the importance of olefins in the petrochemical industry and discusses the limitations of traditional olefin production methods, such as steam cracking and fluid catalytic cracking. The introduction highlights the potential of oxidative dehydrogenation as a more efficient and environmentally friendly alternative, while also outlining the challenges associated with selectivity control and catalyst deactivation. The experimental section details the materials and methods used in the study, including catalyst preparation, characterization techniques, and the experimental setup for the oxidative dehydrogenation reaction. The results and discussion section presents the findings of the study, focusing on the catalytic performance of the different catalysts, the effects of reaction parameters, and the mechanism of catalyst deactivation. The conclusions summarize the key findings of the study and provide recommendations for future research.

Schlüsselwörter (Keywords)

The keywords and focus themes of the text include oxidative dehydrogenation, C3-C4 fraction, olefin production, catalyst design, catalyst characterization, catalytic activity, selectivity, stability, reaction conditions, and steam addition. The study investigates the use of Cr, Mo, and Cr-Mo loaded SiO2 catalysts for the oxidative dehydrogenation of propane-butane fraction to produce olefins, focusing on the optimization of catalyst composition and reaction conditions to maximize olefin yield and minimize catalyst deactivation.

• Authors: Ayodeji Ijagbuji (Author), I. I. Zakharov (Author), T. C. Philips (Author), M. G. Loriya (Author), M. B. Saltzberg (Author), A. B. Tselishtev (Author), R. J. Taylor (Author), B.V. Shevchenko (Author), K. M. Jackson (Author), D. B. Woods (Author), J. K. Johnson (Author)
• Publication Year: 2015
• Pages: 16
• Catalog Number: V292808
• ISBN (eBook): 9783656900023
• ISBN (Book): 9783656900030
• Language: English
• Tags: oxidative de-hydrogenation of C3–C4, C3–C4 conversion, selectivity to olefin, olefin yield, olefin production