Hydroprocessing Catalysts and Processes

The Challenges for Biofuels Production

Bo Zhang, Duncan Seddon

• Publisher: WSPC (EUROPE)
• Year: 2018
• eBook ISBN: 9781786344854
• Topic: Physical Sciences
• Subtopic: Industrial & Technical Chemistry

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The demand for hydroprocessing catalysts has shown an increasing trend, because of their applications in refining of petroleum and biofuels, in order to comply with strict environmental regulations controlling emissions from transportation vehicles.

Transport fuel is dominated by fossil fuels with carbon emission intensive production methods. If we are to move away from these sources, the alternative is to produce liquid fuels from agricultural stocks — crops, crop waste, forestry waste or algae. Converting these feedstocks into high quality fuels is a considerable challenge.

By describing the current status in processing agricultural feedstock into high quality liquid transport fuels, the authors set out the means to develop better chemistry and catalysis for the necessary conversion processes. This book offers an intriguing insight into the mechanisms and protocols involved in new hydroprocessing catalysts and processes, and covers the methods for upgrading these liquids to modern transport vehicles suitable for operation in modern gasoline and diesel engines.

It provides an introduction to the mechanism of hydroprocessing reactions, application of different metals in hydroprocessing, the effect of catalyst supports, applications in refining new feedstock, renewable fuels standards, the management of spent hydroprocessing catalysts, and hydrogen production.

Hydroprocessing Catalysts and Processes will prove useful for both researchers in academe and industry concerned with future fuels development and treatment to produce current and future liquid transport fuels.

--> Contents:

• Preface
• Hydroprocessing and the Chemistry
• Stabilization of Bio-Oil to Enable Its Hydrotreating to Produce Bio-Fuels
• Hydroprocessing Catalysts: Inexpensive Ni Based Non-Sulfided Catalysts
• Catalytic Upgrading of Pinewood Pyrolysis Bio-Oil Over Carbon-Encapsulated Bimetallic Co-Mo Carbides and Sulfides Catalysts
• Hydroprocessing Catalysts for Algal Biofuels
• Effects of Catalyst Support on Hydroprocessing
• Commercial Hydroprocessing Processes for Bio-Feedstock
• Renewable Fuels and Fuel Regulations and Standards
• Spent Hydroprocessing Catalysts Management
• Hydrogen Production

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--> Readership: Graduate students in catalysis, refinery feedstock operations and planners, fuel technologists. -->
Keywords:Hydrodesulfurization;Hydrodenitrogenation;Hydrodeoxygenation;Hydrogenation;Hydrocracking;Hydrodemetallization;Hydroprocessing Catalyst Model;Bio-Oil Stabilization;Ni Based Catalysts;Cobalt-Molybdenum Carbide Catalysts;Algal Biofuels;Support Effect;Commercial Hydroprocessing Processes for Bio-feedstock;Neste MY;BP;Ecofining;ENI;Honeywell-UOP;Bio-Synfining;Vegan;HydroFlex;Renewable Fuels Standards;Spent Hydroprocessing Catalyst;Hydrogen ProductionReview: Key Features:

• Most recent books related to hydroprocessing catalysts were published over 8 years ago
• New challenges in biorefining and petroleum refining have required development of entirely new catalyst formulations and improvements of currently used catalysts
• It is anticipated that the consumption of hydroprocessing catalysts will show a significant increase in the near future

Chapter 1

Hydroprocessing and the Chemistry

Bo Zhang

School of Chemical Engineering and Pharmacy,
Wuhan Institute of Technology, Hubei, China
[email protected]

Abstract

Hydroprocessing is a conventional operation in the petroleum refinery. Recent developments in biofeedstock-derived fuels and stringent environmental legislation brought up new challenges in this traditional area. This chapter reviews hydroprocessing reactions including hydrodesulfurization, hydrodenitrogenation, hydrodeoxygenation, hydrogenation, hydrocracking, and hydrodemetallization, reactivity and reaction pathways of typical chemicals resulted from biofeedstock and petroleum, surface chemistry of hydroprocessing catalysts, and hydroprocessing catalyst models.

Keywords: Hydrodesulfurization, Hydrodenitrogenation, Hydrodeoxygenation, Hydrogenation, Hydrocracking, Hydrodemetallization, Hydroprocessing catalyst model

1.1.Introduction

Hydroprocessing refers to a variety of catalytic hydrogenation (HYD) processes which saturate unsaturated hydrocarbons and remove sulfur (S), nitrogen (N), oxygen (O), and metals from petroleum streams in a refinery [1]. Most recently, the hydroprocessing process has been applied to the biobased feedstock such as vegetable oils and algal oil. Generally, hydroprocessing can be categorized as hydrotreating and hydrocracking. Hydrotreating removes heteroatoms and metals and saturates carbon–carbon bonds with minimal cracking, while hydrocracking that is conducted under more severe conditions breaks carbon–carbon bonds and drastically reduces the molecular weight of the feed [2].

1.1.1.Hydroprocessing of fossil fuels

Historically, the hydroprocessing technology was first applied to coal HYD, which was developed by a French chemist, Pierre Eugène Marcellin Berthelot [3]. Later, the industrial development of the coal-HYD process was accomplished by a German scientist, Friedrich Karl Rudolf Bergius, who invented the Bergius process [4]. This HYD process converted coal, tar, or heavy oil into gasoline, and it was found that cobalt (Co), molybdenum (Mo), and tungsten (W) sulfides were especially active catalysts [5]. The patent of the Bergius process was sold to the BASF, and several plants were built with an annual capacity of 4 million tons of synthetic fuel before World War II [6]. After World War II, a “hydroforming process” using the Co–Mo catalysts was investigated by Union Oil (US) for the decomposing all types of sulfur compounds of petroleum fractions [7]. Since then the major use of mixed sulfides has been shifted to hydroprocessing of petroleum feedstocks with Co or nickel (Ni) promoted Mo or W catalysts usually supported on γ-Al₂O₃. The basic components of hydroprocessing catalysts have remained the same for over 50 y.

Environmental regulations are the major driving force for the hydroprocessing operations. For example, fuel quality and it emissions are regulated by US Environmental Protection Agency (EPA) under the authority of the Clean Air Act Amendments of 1990 in the United States. Environmental regulations limit sulfur levels in diesel fuels. A sulfur limit of 500 ppm (0.05 wt.%) was applied for the “low-sulfur” diesel fuel used in heavy-duty highway engines in October 1993. Beginning in June 2006, the maximum sulfur level of 15 ppm was enforced for the ultra-low-sulfur diesel (ULSD) used as the highway diesel fuel. For gasoline, the refinery annual averages required by the Tier 2 and Tier 3 gasoline sulfur standards, which have been effective from Jan 1, 2017 for most refiners, are 30 ppm and 10 ppm, respectively [8]. Table 1.1 summarizes the trends of diesel sulfur fuel specification for highway transportation vehicles in selected regions and countries [9]. To date, most countries require the sulfur content in transportation fuels to be below 50 ppm.

Table 1.1.Sulfur standards for diesel in selected regions and countries. (Adapted with permission from Ref. [9]. Copyright © 2010 Elsevier.)

Regions/countries	Sulfur (ppm)	Year of implementation
Argentina	50	2008
Brazil	500	2008
	50	2009
Chile	350	2007
	50	2010
Mexico	500	2005
	15	2009
Peru	50	2010
Uruguay	50	2009
China	20,000	2000
	500	2005
	50	2012
Hong Kong	50	2007
India	350	2005
	350	2010
	50	2010
Singapore	50	2005
Taiwan	50	2007
Australia	500	2002
	10	2009
Kuwait	2,000	2008
	50	2010
Saudi Arabia	800	2008
	10	2013
Bahrain, Lebnon, Oman, Qatar, UAE	50	2008
Qatar, UAE	10	2010
Bahrain	10	2013
Iran	50	2008
Jordon	10,000	2008
	350	2012
Russia	500	2008
	50	2010
EU	500	1996
	350	2000
	50	2005
	15	2009
USA	500	1993
	15	2006
Japan	500	1997
	50	2003
	15	2005

Thus, hydroprocessing is a more important unit operation in petroleum refining industry and synthetic crude upgrading [10]. The increased use of refinery catalysts can help refiners meet fuel standards, manage operational efficiency, and enhance conversion and selectivity. Such demands require that the hydroprocessing catalysts possess not only high activity but also different activity profiles with respect to various functionalities [11]. Accordingly, the worldwide hydrotreating catalyst consumption in 1990 was approximately 35,000 t/y and in the range of 150,000–170,000 t/y in 2007 with an anticipated 4–5% annual increase [12].

1.1.2.Hydroprocessing of biomass-derived fuels

The study on conversion of cellulosic biomass into liquid fuels (i.e., bio-oil or biocrude oil) has a history of over 70 y [13, 14]. Over the past 35 y, hydroprocessing including catalytic hydrotreating and hydrocracking of bio-oil in both batch-fed and continuous flow bench-scale reactor systems has been underway, primarily in the US and Europe [15]. This application of hydroprocessing is an extension of petroleum processing.

Typical thermochemical processes for production of bio-oils from biomass include hydrothermal liquefaction and pyrolysis. Both processes convert feedstock to liquid products. An advantage of the thermochemical process is that it is relatively simple, usually requiring only one reacto...

Table of contents

• Cover Page
• Halftitle
• Catalytic Science Series
• Title
• Copyright
• Contents
• Preface
• About the Editors
• Chapter 1. Hydroprocessing and the Chemistry
• Chapter 2. Stabilization of Bio-oil to Enable Its Hydrotreating to Produce Biofuels
• Chapter 3. Hydroprocessing Catalysts: Inexpensive Ni-Based Nonsulfided Catalysts
• Chapter 4. Catalytic Upgrading of Pinewood Pyrolysis Bio-oil over Carbon-Encapsulated Bimetallic Co–Mo Carbide and Sulfide Catalysts
• Chapter 5. Hydroprocessing Catalysts for Algal Biofuels
• Chapter 6. Effects of Catalyst Support on Hydroprocessing
• Chapter 7. Commercial Hydroprocessing Processes for Biofeedstock
• Chapter 8. Renewable Fuels and Fuel Regulations and Standards
• Chapter 9. Spent Hydroprocessing Catalysts Management
• Chapter 10. Hydrogen Production
• Index