Electron Magnetic Resonance (EMR) – Research and Industrial Applications

By AZoM

Table of Contents

Introduction
Academia
     Teaching
     Research
Food Industry – Cooking Oil
Transport and Engineering Industries – Lubricants
     Oil Oxidation
     Soot Accumulation
     Asphaltene Contamination
Conclusion
About Oxford Instruments Magnetic Resonance

Introduction

Oxford Instruments has made the AffirmoEX technique of Electron Magnetic Resonance (EMR), also known as Electron Spin Resonance (ESR) or Electron Paramagnetic Resonance (EPR), accessible to almost every laboratory, from academic research & teaching to quality assurance & process control. Firstly developed over sixty years ago, EMR is a well established technique. EMR measures unpaired electrons in a sample which feature free radicals and complexes containing transition metal ions. EMR is a highly selective technique and it is the first choice for free radical and transition metal oxidation state study. EMR can be used in a wide range of applications. These include oxidation, free radical polymerization and a wide range of biochemical processes. Similarly, the understanding of the oxidation state of inorganic transition metal complexes gives vital information to the analysis of processes such as those associated with catalysis.

Academia

There are two areas in the academic field where Electron Magnetic Resonance plays an important role: teaching and research. The compactness, simplicity and affordability of the Oxford Instruments AffirmoEX create new opportunities in both these areas.

Teaching

Since EMR instruments are highly expensive, in the past, they have rarely been used in teaching. Oxford Instruments has removed these constraints and has made EMR a potential essential tool for teaching analytical chemistry. In order to assist the reintroduction of EMR to the syllabus, Oxford Instruments has partnered with Professor Reef Morse, a lifetime specialist in EMR (ESR/EPR). Together, a comprehensive package has been developed to assist with EMR tuition. The EMR curriculum module includes an Oxford Instruments AffirmoEX benchtop EMR instrument with a set of defined experiments to teach students the fundamentals of the technique and how it can be used to obtain valuable chemical information. It will also contain a complete documentation including a bibliography to enable teaching professionals to deliver an up-to-date and relevant course module to their students.

Research

EMR (ESR/EPR) is the preferred technique for monitoring free radical processes and transition metal complex oxidation states. Many areas of research such as biochemistry, polymerization, catalysis, organic synthesis and green chemistry require the insight that EMR can bring. With the Oxford Instruments AffirmoEX, researchers can finally benefit from the information that EMR brings to the table.

Food Industry – Cooking Oil

Food preparation and storage processes are typically free radical processes. These include the oxidation of cooking oils and the degradation of food over storage times. Oxford Instruments has been offering quality control solutions to the food industry for a long time with their benchtop NMR system (the MQC) in order to measure oil, fat and moisture. The Oxford Instruments AffirmoEX benchtop EMR system complements this activity with its ability to study the oxidation of cooking oils. Rancidity of cooking oils results from a breakdown of the oil caused by a free radical process, which is both temperature and oxygen dependent. This causes the degradation of the long chain fatty acids into tinier molecules, which give a distinctive bad odour and/or flavour. The traditional industrial method employed to evaluate the oxidative stability of oil involves the measurement and reporting of a parameter known as peroxide value (PV). Measuring the PV is a time-consuming and inconvenient procedure, which as well requires comparison to standards. On the contrary, EMR guarantees repeatable and accurate data, obtained quickly and directly without the need to correlate every measurement to standards.

Transport and Engineering Industries – Lubricants

In many industrial applications, the maximization of equipment lifetime and productivity is crucial and require the understanding of the behavior of lubricating oils. Such knowledge is required for reduction of operating costs and avoiding downtime caused by failures. Regular measurements can help identifying potential problems early. The Oxford Instruments benchtop EMR offers information on the oil characteristics and on the presence of contaminants. Three key parameters are ideally measured by EMR.They are: oil oxidation, soot accumulation and asphaltene contamination.

Oil Oxidation

The primary breakdown mechanism of lubricating oil is thermal oxidation. Oxidation is a free radical process and, as EMR is the only technique that directly measures free radicals, it is appropriate for monitoring it. The evaluation of the oxidation state of oil by EMR is directly correlated to the usable lifetime of the oil.  

Soot Accumulation

The accumulation of soot in oils reduces the efficiency and may cause catastrophic failure of an engine. The surface of soot particles is characterized by the presence of unpaired electrons which can be identified by EMR. Regular monitoring is key to prevent the build-up of damaging soot levels and can as well be used to identify poor combustion.

Asphaltene Contamination

Marine engines operate on bunker fuel. This considerably unrefined product frequently has high asphaltene content. In a well maintained engine, the asphaltenes are combusted without polluting the lubricating oil but, if unburned, asphaltene gets past the piston rings into the lubricating oil and the piston undercrown deposits are likely to form along with crankcase sludge build-up. These can lead to catastrophic engine failures. Asphaltene has a characteristic spectrum and can be easily monitored by EMR. In addition, vanadium, primarily in the form of vanadyl porphrin, also has a characteristic eight-line EMR spectrum which can also be used to monitor fuel dilution of the lubricating oil.

Conclusion

Compact, simple and affordable EMR instrumentation has paved the way for a large number of opportunities to use this highly selective and informative analytical technique.

About Oxford Instruments Magnetic Resonance

Oxford Instruments Magnetic Resonance are committed to the development and manufacture of information-driven solutions for novel applications in life sciences, research and industrial process control. The company knowledge was founded in the field of Nuclear Magnetic Resonance (NMR) instrumentation, receiving high recognition for its innovation dating over forty years. Today Oxford Instruments Magnetic Resonance are focused on solving complex and often unique technology problems for the understanding of biomolecular structure and function across industrial, life science and drug discovery applications. In the industrial process area, the low field benchtop instruments offer fast, accurate and simple measurement solutions to routine Quality Control problems.

This information has been sourced, reviewed and adapted from materials provided by Oxford Instruments Magnetic Resonance.

For more information on this source, please visit Oxford Instruments Magnetic Resonance.

Date Added: Apr 10, 2012 | Updated: Jun 11, 2013
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