4.4 Mechanism of Wax Crystallization and Modification 170
4.4.1 Wax Crystal Compositions and Structures 170
4.4.1a Compositions 170
4.4.1b Structures 173
4.4.2 The Crystallisation Process 175
4.4.3 n-Alkane-Wax Nucleation 175
4.4.4 Effects of Additives on Nucleation 177
4.4.4a EVAC Nucleator 177
4.4.4b Nucleator Additives with Crystallinity, PEG Esters and PEPEP 179
4.4.5 n-Alkane-Wax Crystal Growth 181
4.4.5a Comparison of Untreated and WCM Treated Wax Crystals 181
4.4.5b Mechanism of Crystal Growth 182
4.4.5c Effects of Additives on Crystal Growth 184
4.4.5d Very Small Wax Crystals and Wax Anti-Settling 188
4.4.5e Cloud Point Depression 190
4.4.5f Rapid Growth of Wax Crystals in Narrow Boiling Distillates 191
4.6 Cold Flow Tests 193
5 Protection of Metal Surfaces in Fuel Systems: Lubricity Improvers and Corrosion Inhibitors 209
5.1 Lubricity: Introduction 209
5.2 Detailed Lubricity Problems 211
5.2.1 Jet Fuel 211
5.2.2 Gasoline 212
5.2.3 Diesel 214
5.3 Chemistries of Lubricity Improvers 216
5.3.1 Carboxylic Acids as Lubricity Improvers 216
5.3.2 Carboxylic Esters and Amides as Lubricity Improvers 218
5.4 Understanding of Boundary Friction and Lubricity 220
5.5 Introduction: Corrosion in Fuel Systems 224
5.6 Corrosion Issues in Various Fuels 226
5.6.1 Automotive Gasoline and Diesel Fuels 226
5.6.2 Jet Fuels 227
5.6.3 Heating Oils 228
5.6.4 Distillate Marine Fuels and Off-Road Fuels 229
5.6.5 Heavy (Residual) Fuels 229
5.7 Chemistries of Fuel Corrosion Inhibitors 230
5.7.1 Corrosion by Water/Oxygen and by Carboxylic Acids 231
5.7.2 Corrosion by Sulphur 235
5.7.3 Corrosion by Vanadium Pentoxide 240
5.8 Mechanisms of Corrosion and Its Inhibition 241
5.8.1 Corrosion by Water/Oxygen and by Carboxylic Acids 241
5.8.2 Corrosion by Sulphur 244
5.8.3 Corrosion by Vanadium Pentoxide 245
6 Combustion Improvers 261
6.1 The Need for Combustion Improvers 261
6.2 Combustion Improver Specific Problems 262
6.2.1 Gasoline Engine Knock and Octane Boosters 262
6.2.2 Diesel Knock and Cetane Improvers 265
6.2.3 Combustion Improvers for Heating Oils and Heavy Fuels 269
6.2.4 Combustion Improvers for Particulates in Diesel Engine Exhausts 270
6.3 Mechanisms of Soot Formation and Its Removal 275
6.3.1 The Formation of Soot 275
7 Additives to Treat Problems during the Movement and Storage of Fuels 287
7.1 Introduction 287
7.2 Drag Reducing Agents 288
7.2.1 The Pipeline Problem 288
7.2.2 Chemistries of DRAs 289
7.2.3 The Process of Drag Reduction 291
7.3 Static Dissipaters 291
7.3.1 The Problem of Static Electricity in Fuels 291
7.3.2 Chemistries of Static Dissipaters 294
7.3.3 Understanding Static Dissipaters 299
7.4 Antifoam Additives 302
7.4.1 The Problem of Foaming 302
7.4.2 What Antifoams Do and Their Chemistries 303
7.4.3 Syntheses of Silicone Antifoams 304
7.4.4 How Antifoam Additives Work 306
7.5 Demulsifiers and Dehazers 307
7.5.1 The Problem of Water-in-Fuel Emulsions or Haze 307
7.5.2 The Chemistry of Demulsifiers 308
7.5.3 The Process of Demulsification 313
7.6 Anti-Icing 315
7.6.1 The Problem of Icing 315
7.6.2 The Gasoline Icing Problem 316
7.6.3 The Jet Fuel Icing Problem 317
7.6.4 Jet Fuel Anti-Icing Additives 319
7.7 Biocides 320
7.7.1 Problems 320
7.7.2 Chemistries of Biocides Used in Fuels 321
Index 335
Available to OhioLINK libraries.
"It is not only chemists who realise the ubiquitous nature of chemical technology in our modern environment, though it may be that only chemical technologists fully appreciate just how wide ranging are the products of the chemical industry. The scope of the chemical technology can be thought of, broadly, as the applications - such the dyes, pharmaceuticals, and textiles - and within each application and subdivision, there is a whole technology specific to that application. One broad application is chemicals in the oil industry, which includes a few subdivisions: those for exploration and recovery, those in refineries and those for the finished products of oils and fuels. Additives for lubricating oils have been well covered in the available literature while fuel additives have been covered in much less detail and provide an area of expertise whose existence is largely unknown to the public. This book is concerned with the problems addressed by fuel additives, their chemistries, and scientific insights into their actions. In this book, chapters on the individual additive types generally follow a discussion of the problem that they address, what they do to alleviate the problem, their chemistries - including their preparations - and some understanding of how they work. Many fuel additives are derived from existing areas of technology in other applications; degradation by corrosion and autoxidation, for example, are wide ranging problems that have spawned studies to understand them and additives to overcome them. Some additives started life in other parts of the petroleum industry such as fuel detergents, that are derived from lubricating oil dispersants, and demulsifiers, that are heavily used in crude oil recovery. As a result of this wide relationship with other applications, the sources drawn on for each chapter are also wide ranging in technical area and in literature type. There are some publications that provide useful summaries of fuel additives and their use. In particular, the booklets provided by the Technical Committee of Petroleum Additive Manufacturers in Europe (ATC) provide a paragraph on each additive/fuel combination. The Automotive Fuels Reference Book provides extensive coverage of the production, distribution and use of fuels along with details of internal combustion engines, along with few chapters on gasoline and diesel fuel additives. Books on refining are plentiful, but they usually pay little or no attention to fuel additives. However, to understand fuels and the roles of and incentives for the use of fuel additives, it is necessary to know something about refineries. So, the first chapter summarises refinery operations to an extent that discussions of fuels in the following chapters is understandable. This first chapter is an attempt to cover problems other than those occurring from of the way in which fuels are transported and used, so it also includes such items as the proportions of different fuels used at different times and places - the demand barrel; it also introduces the range of fuels and additives, and the influence of taxation"--
About the Author
Robert D. Tack, PhD, currently retired, finished his career at Infineum UK Ltd developing fuel additives. Prior to that Dr. Tack worked at Exxon Chemical in the PARAMINS division developing lube oil and fuel additives.