June 12, 2007
NMR Analysis of Jasmine Absolute - jasmine officinale - Egypt
NMR analysis of Jasmine Absolute.
For
more information on NMR of Essential
Oils visit the PNA website.
May 15, 2007
Omega-3 Dietary Supplements - NMR Analysis
Fish Oils - Flaxseed Oils
NMR is extensively utilized to analyze fish oils and edible oils high in omega-3 fatty acids.
Examples of 1H and 13C data and analysis are provided below:
13C NMR Analysis of Fish Oil Supplement
13C NMR of Flaxseed Oil Supplement
May 14, 2007
Wine Analysis by NMR
Brief Overview of Wine Analysis by 1H and 13C NMR
Wine analysis by 1H or 13C NMR can be used to follow acid content during maturation. Lactic, succininc and acetic acid can be followed readily by both techniques and presence of sugar, glycerol, and methanol can be observed.
Chemometric approaches are starting bear fruit with respect to quantitative analysis:
NMR Without Solvents - Biodiesel Production Process - FAME, Glycerol, FFA, and Methanol
1H and
13C NMR NMR is typically
obtained using deuterated NMR solvents
to lock the field during acquisition. In
some cases the use of these solvents is
problematic as it prevents observation
of solublized phases present in the
sample. As an example we show here the
NMR data obtained on a biodiesel
production process. One of the major
issues with the FAME product is the
presence of glycerol in the product. NMR
analysis is usually performed by
dissolving the FAME in CDCl3
in which glycerol is completely
insoluble. Thus NMR analysis performed
in this way does not allow analysis of
residual glycerol content. However, if
the FAME is run neat this issue does not
arise.
Another
analysis of enormous interest from the
process control standpoint is the
analysis of the glycerol/methanol phase.
This phase contains considerable free
fatty acids as well as the glycerol by
product and excess methanol from the
transesterification process. The three
components are readily observed by 1H
and 13C NMR, and 23Na
can be used to observe NaOH content in
the phase. Finally the shift and shape
of the observed OH resonance can yield
information on the pH of the glycerol
phase. Typically this analysis is done
in DMSO-d6
Below are some examples of NMR obtained without a deuterated solvent:
Difference in aliphatic carbon distribution between FAME phase and Free Fatty Acids (FFA)
found in the glycerol - methanol phase.
1H NMR of aliphatic component found in the FAME phase as well as the FFA in the glycerol phase.
May 10, 2007
NMR PhD Position with Damien Jeannerat at Universite de Geneve
I am posting this on behalf of Damien Jeannerat.
April 16, 2007
Monitoring of a Biodiesel Transesterification Process with a TD-NMR Spectrometer
The 19.5 MHz Spintrack NMR analyzer was utilized to study a FAME biodiesel production reaction. The samples analyzed were:
1) Used vegetable oil
2) Partially transesterified biodiesel product (bad biodiesel)
3) High yield FAME biodiesel product
4) Glycerin by-product from the process
CPMG T2 decays were generated and then that data was processed with a inverse laplace transformation to produce T2 distribution profiles.
NMR Experiment explanation is given below:
The CPMG data obtained on the four samples is shown below:
The T2 distribution profiles obtained by inverse Laplace transformation of the CPMG data are shown below:
Plainly TD-NMR can play a role in monitoring the biodiesel production process.
TD-NMR Analysis of Catalytic Cracker Feedstocks
The 19.5 MHz Spintrack NMR analyzer was utilized to study a large series of vacuum gas oils and FCC feeds for which PNA also has laboratory test data.
The analysis was performed on a SpinTrack 19.5 MHz TD-NMR spectrometer - CPMG T2 decays were generated and then that data was processed with a inverse laplace transformation to produce T2 distribution profiles. These T2 distribution profiles are currently being correlated to physical and chemical property data.
NMR Experiment explanation is given below:
The CPMG data obtained on the four samples is shown below:
The T2 distribution profiles obtained by inverse Laplace transformation of the CPMG data are shown below:
The correlation between T2 distribution and the metal content, viscosity, distillation range, density, asphaltene content are all being investigated at the current time.
April 15, 2007
13C NMR of FAME Biodiesel
Below are examples of 13C NMR data obtained on biodiesel (FAME) and the vegetable oil precursor that it was made from by transesterification process involving microwave activation of the reaction between triglycerides and methanol in the presence of a caustic catalyst. Process NMR Associates is developing correlations between 13C NMR data and biodiesel properties stipulated in ASTM 6751.
Detailed 13C NMR Analysis of Hydrocarbons - Patent Applications
Today one often finds hydrocarbon mixtures described by the detailed carbon type analysis that is possible from 13C NMR.
Many petroleum related products are being described in this way in patents leading to a novel way of describing a material and restricting others from using those same materials in products of their own. See Exxon, Mobil, and Chevron patents such as:
6,090,989 ; 6,210,559 ; 6,059,955 ; 6,846,778 ; 20050077208 ; and 20050077209
In this PDF file we have shown some of the details present in a 13C NMR spectrum on petroleum products such a base oils, gas oils, diesels, etc.
There are some issues with the assignements of many of these patents … for more details on how NMR might be of use in the patent process contact John Edwards
April 14, 2007
Naphtha Chemistry Analysis by 1H NMR
1H NMR has been used extensively by Process NMR Associates to determine PIONA analysis of Naphthas and to determine detailed aromatics breakdown in aromatics unit feeds, products, and intermediate products. Below are a few examples of naphtha chemistries that are observed and quantified by 1H NMR.
Conjugated Olefin analysis is performed by a combination of HH-COSY and 1D 1H NMR.
For more details contact John Edwards
NMR Job Opportunity - Saudi Aramco
Saudi Aramco Research and Development are searching for an experienced NMR spectroscopist - see details
Anyone who has NMR employment opportunities should contact Process NMR Associates. We would be happy to post you job listing to our blog and website.
If interested please e-mail a job description, requirements, and contact information to John Edwards
April 13, 2007
Quantifying Adulteration of Licorice With Maltodextrin by Liquid and Solid-State NMR
Three samples were analyzed to determine if liquid or solid-state NMR techniques could be utilized to quantify adulteration of licorice powders by maltodextrin. Samples analyzed were:
Maltodextrin, Licorice #1, Licorice #2
Licorice #1 and Licorice #2 were analyzed by a combination of liquid-state 1H and 13C NMR on a Varian Unity-300 spectrometer, and solid-state 13C NMR on a Varian UnityPlus 200 spectrometer. The resulting spectra are shown in the attached plots.
One of the Licorice samples is adulterated by maltodextrin to an unknown concentration, the other licorice sample is pure licorice. Which sample was which was not known during the analysis. Initially it was hoped that the addition of maltodextrin to the licorice would be readily observed as new peaks appearing in the spectrum of the licorice sample. However, it can be seen that in both the 1H and 13C NMR there is considerable overlap of the peaks in the spectra of pure licorice and maltodextrin.
When no observable maltodextrin peaks could be assigned it was decided to simply use the quantitative integral data from the regions of the spectrum where the maltodextrin overlaps with the licorice spectrum compared to the integrals obtained from regions solely assignable to licorice. In Tables 1-3 are the quantitative results for each of the experiments performed.
Table 1: 1H NMR Integral Regions
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Normalized on Reg 4
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Regions 1 and 2 contain maltodextrin/licorice peaks.
Regions 3 and 4 contain only licorice peaks …. Data was norma lized to region 4. The norma lization norma lizes the licorice signal intensity. Thus the increased intensity of regions 1 and 2 in sample #1 is indicative that this sample contains maltodextrin. Samples #1+ and #2+ were made by adding more maltodextrin to the samples. Sample #1+ contains a further 10.9 wt % maltodextrin, while sample #2+ contains 11.4 wt% maltodextrin. The values were used to calculate the maltodextrin content in sample #1.
The 1H analysis indicates that there is 3.3 wt% maltodextrin in sample #1
Table 2: 13C NMR Integral Regions
|
Normalize on Region 7
|
|
|
|
|
|
|
|
Regions 1-3 were common to licorice and maltodextrin signals, while regions 4-7 were exclusive to licorice signals. Normalization on region 7 sets the licorice at a norma lized intensity. Again the intensty of regions 1-3 increases from sample #2 to sample #1 indicating the presence of maltodextrin in sample #1.
Calculation indicates that there is 6.1 wt% maltodextrin in the sample.
Table 3: Solid-State 13C Integral Regions
|
Solids 13C CPMAS
|
Normalized to Reg 3
|
|
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Region 1 contains maltodextrin and licorice signals, while regions 2 and 3 contain only licorice signals.
Again, the intensity of region 1 increases from sample #2 to 31 upon norma lization of the licorice only region 3. This confirms the presence of maltodextrin in sample #1. Samples #2+ and #1+ were not analyzed by solid-state NMR. This 13C analysis is much faster than the liquid-state NMR and would be a plausible short cut to quantify maltodextrin content.
Upon completion of the analysis it was revealed that the adulteration value was 5% maltodextrin.
March 30, 2007
Process NMR Symposia to be held at EAS 2007
John Edwards of Process NMR Associates has organized and sponsored two symposium sessions at the Eastern Analytical Symposium in Somerset New Jersey, November 12-15, 2007. One session will focus on high-resolution process NMR and the other on applications of TD-NMR in process control. The speakers and talk titles are listed below. Check the EAS site for exact details on the date and time of the sessions (EAS website). If you are interested in attending and would like to submit a paper for presentation visit the EAS Abstract submission site.
Session Title: Process NMR Technology - High Resolution NMR
John Edwards, Process NMR Associates, “Introduction to NMR in Process Control”
Miko DeLevy, Qualion NMR Analyzers, “Standardizing and Stabilizing NMR Calibration Transfer”
Paul Giammatteo, NMR Process Systems, “More from the Barrel - On-line NMR Increases Diesel Production and Quality”
Marcus Trygstad, Invensys Process Systems, “Taking NMR into the Refining Process: Best Practices and Benefits”
Andreas Kaerner , Eli Lilly, “Get Your Head Out of the Sand: Use of Reaction-NMR to Better Understand Reactions in Process Development”
Veena Bansal, Indian Oil Corporation, “Direct Prediction of Gasoline Properties for Monitoring Refinery Processes by 1H NMR Spectroscopy”
Session Title: Process NMR Technology - TD-NMR
Harry Xie, Bruker Optics, “Recent Developments in Time-domain NMR and its Applications in Polymer Industry”
Vaughn Davis, Progression Inc, “Time Domain NMR: Uses and Contributions to Process Control”
YiQiao Song, Schlumberger-Doll, “Recent Progress of NMR and MRI in Petroleum Exploration”
Maziar Sardashti, ConocoPhillips, “Applications of TD NMR to Laboratory and On-line Polymer Analysis”
Sergey Kryuchkov, University of Calgary, “Challenges in Online Water Cut Monitoring of Heavy Oil Thermal Operations Using Low Field NMR”
Chris Borgia, Colgate Palmolive, “Benchtop Fluoride NMR: A Rapid QC/QA Method”
March 25, 2007
Trans Fat Analysis by NMR
A series of Trans Fat standards was purchased from AOCS. The ability of 1H and 13C NMR to predict Trans Fat Content as well as
Saturated, Poly-unsaturated, and Mono-unsaturated Fat Content
The data of the samples is presented in the table below:
PLS regression techniques were used to correlate 1H and 13C NMR spectral variation to the unsaturation level and type of unsaturation of the samples.
Processed 13C data is shown below:
1H NMR data is shown below:
The following correlations were obtained from the 13C NMR data.
NMR Analysis of Essential Oils - Example of Sri Lankan Citronella
The data below shows the ability of 13C NMR to assign the natural product distribution found in essential oils. Once assignment of the oil hgas been obtained by 13C NMR the 1H NMR can also be assigned. For QA/QC a benchtop 60 MHz system has enough resolution that authenticity of essential oils can be performed either visually of by PCA type analysis.
Ger - Geraniol GerAc - Geranyl Acetate iEugMe - Methylisoeugenol Bor - Borneol
aPin - alpha-pinene Lim - Limonene tOci - trans-beta-Ocimene Cen - Camphene
Cllo - Citronellol Clla - Citronellal GenD - Germacrene D aCal - Citral A (Geranial)
aTol - alpha-Terpiniol cOci - cis-beta-Ocimene Myr - Myrcene
March 24, 2007
Process NMR for Transesterification Monitoring and Certification of Biodiesel
1H NMR has been used extensively to analyze biodiesel the vegetable oil feeds, reaction intermediates, and final products of the biodiesel transesterification process.
See Oliviera et al, Talanta 69 (2006) 1278-1284 and Gnothe, J. Am. Oil Chem. Soc 78, 1025-1028 (2001)
The final biodiesel product is a B5 (5% Biodiesel) or B20 (20% Biodiesel) blend of biodiesel in refinery produced diesel fuel. Researchers have performed method developments to analyze the biodiesel content in diesel fuels by NIR using 1H NMR as the primary method to quantify the biodiesel content. (See Jin et al, Fuel 86(7-8), 1201-1207 (2007) and Knothe J. Am. Oil Chem. Soc. 77 489-493 (2001). Process NMR at 60 MHz can be used to quantify the biodiesel directly. Below is an example slide of a biodiesel 1H NMR spectrum compared to two different diesel fuel spectra.
The chemistry that is directly observed in the NMR spectrum as well as the distinct chemical regions that are present in the diesel and biodiesel make this analysis relatively straightforward. Chemometrics can be used or quantitation can be obtained directly from a simple spectral calibration.
Biodiesel Production Monitoring
NMR can be used to follow the reaction of biodiesel directly, the following slides show the steps in the transesterification process.
Glycerol content in the biodiesel or unconverted vegetable oil content can be determined easily directly from the spectrum.
Expansion of Incomplete Reaction Series
Work is currently underway to develop NMR calibration models that can predict the various quality parameters specified in ASTM D6751 for biodiesel.
These calibrations, based on either 1H or 13C NMR, when validated would allow rapid testing of biodiesel production batches and would make complete analysis of small production batches economically feasible (there is no point making 300 gallons of biodiesel if you have to perform $1300 of testing on the batch).
July 28, 2006
New CAPP NMR Method - Olefin Content of Crude Oils, Condensates, and Diluents by 1H NMR
The Canadian Association of Petroleum Producers has produced a test method to quantify olefins in crude oils, condenates and diluents. The method is particularly aimed at heavy oils and bitumens and their products that are not amenable to traditional olefin analysis. The method is published at the following link. We have developed many methods similar to this and have the ability to quantify and speciate the olefins present in the sample. The current CAPP method developed by the Canadian Crude Quality Technical Association (CCQTP) can be used to obtain total olefin content. Further NMR analysis and a few other experiments would allow some more detailed olefin chemistry distributions to be determined as well as observe the presence of conjugated diolefins that would be particularly troublesome in the processing of these materials. 1H NMR spectroscopy can be used very effectively to obtain many chemical and physical properties of crudes, heavy crudes, bitumen, and the distillate products that are produced by these materials. 1H NMR spectral correlation with these properties by PLS or non-linear PLS regression can yield extremely robust models, and for the chemical properties much more detailed chemical structure information can be obtained fro combining 13C NMR data with 1H NMR results.
CCQTP is an association with members that span multiple segments of the Canadian oil industry -it’s history, mission, and membership can be found at the site.
On a related note an excellent technical site dealing with crude oil quality issues cane be found at the Crude Oil Quality Group website, which is a consortium with the following membership, dedicated to developing test methods and quality standards for crude oil trading that go well beyond the traditional gravity and sulfur measurements currently used. There are many additives, processing fluids, corrosive materials that can be found in crude oils that can cause processing issues for the buyer who purchases simply based on density and sulfur. The group has made public much of it’s meeting agenda archives and the presentations given at those meetings. It is an interesting read for those interested in petroleum chemistry issues.
At PNA we have been developing some high field and low field NMR techniques, looking at chemistry and relaxation in crude oils with naphthenic acid and corrosion issues. We would be interested in hearing from anyone interested in woprking with us to develop a relatively straight forward method for NAN and TAN analysis by NMR methods.
Quantitative NMR
Found and interesting site touting quantitative NMR as a new concept….seems strange as 99% of the NMR work I have done is considered quantitative. There is a perception out there that 13C NMR is always qualitative. This has been confirmed to me in conversations with organic chemistry professors who will perform quantitative 1H NMR all day long and even justify higher magnetic field instruments based on lack of resolution in 1H data as they have the perception that 13C is purely qualitative and don’t think of the superior resolution and chemical shift information present in 13C spectra. The website is at qnmr.com, and contains an excellent petroleum chemistry example of the development of quantitative 13C NMR for aromaticity determination by Joe Ray, ex Amoco NMR researcher.
There is also an excellent link to a paper on the quantitative NMR of natural products.
Excellent Solid-State NMR Overview at Durham University
There is an excellent overview of solid-state NMR at my alma mater Durham Univeristy in the UK. The page can be found at the following link.
July 21, 2006
July 3, 2006
Process NMR Paper at San Francisco ACS Meeting - September 2006
ENITechnologie will be presenting a paper on the on-line application of NMR in lube plant operation at the upcoming ACS Meeting in San Francisco
Experiencing Process MRA Industrial Lube Plant Application – Roberto Giardino1, Silvia Guanziroli1, Cinzia Passerini1, and Antonio Farina2. (1) EniTecnologie S.p.A, via Maritano, 26, San Donato M.se (MI), 20097, Italy, (2) Divisione Refining & Marketing – Raffineria di Livorno, Eni S.p.A, via Aurelia, 7, 57017 Stagno (LI), Italy
In a conventional base oil production plant the operating conditions needed to produce products at a desired specification are very sensitive to feed quality. At Livorno refinery an on-line Process Magnetic Resonance Analyzer (MRA) has been installed to identify the feedstock and product composition and properly set an advanced process control system. By using MRA it is possible to reduce the product quality give-away due to feed quality variation. In this work the industrial experience acquired is reported.
Characterization, On-Line Monitoring, and Sensing of Petroleums and Petrochemicals 8:30 AM-11:30 AM, Thursday, 14 September 2006 Sheraton Palace—Telegraph Hill
Division of Petroleum ChemistryThe 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006
June 19, 2006
Application Overview for Spin Track TD-NMR Spectrometers
Due to it’s broad versatility the Spin Track NMR Hardware supports all standard NMR routines such as AOCS Cd 16b-93, AOCS Cd 16-81, ISO 8292, IUPAC2.150 and creative scientific research. Spin Track has been successfully approved in the food and polymer industries for routine analysis. If your application is not described below please contact John Edwards for discussion.
Solid
Fat Content (SFC) Analysis
The quality of food products containing
fats and oils depends on solid fat
content (SFC). SFC
determination is an essential
measurement in the baking,
confectionery, and fat industries. NMR
has been established as the method for SFC
determination by ISO
8292. Measurements of SFC
by the Spin Track NMR
analyzer can be performed quickly and
accurately with great benefit for the
manufacturer.
Simultaneous
Rapid-Determination of Oil and Water in
Seeds
Sunflower, soybean, groundnut, rape and
mustard are appreciated for their oil
content, but excess of water content
reduces their price. Thus, an accurate
and fast determination of oil and water
content is important to both
manufacturers and customers. The Spin
Track NMR
analyzer meets ISO
10565 requirements and gives
the possibility to simultaneously
determine of oil and water content.
Oil/Fat
and Moisture analysis in Chocolate,
Powdered Milk, Cheese and other Food
Products
Time of storage of food products depends
strongly on moisture content. Excess
moisture leads to microbiological
activity and can make food consumption
dangerous. Fat and moisture content also
heavily influence taste.
Manufacturers are also regulated to
disclose the exact information on the
fat content of their products. NMR
is the most rapid and exact method to
determine these essential parameters.
The Spin Track NMR
analyzer is especially suitable for
regular analysis of food quality.
Curing Degree and Elasticity Analysis in Rubber-Type Materials
Over the past years Rheology has become widely accepted as a tool in the investigation of rubber properties. However, rheological testing equipment can be extremely expensive and complicated. NMR is very sensitive to the structure and properties of investigated rubber materials. The Spin Track NMR-analyzer allows investigators to obtain data complementary to rheology and can also prove to be more informative.
Moisture
and Crystallinity Analysis in
Polysaccharides
Polysaccharides like chitin, chitosan
etc. are widely used because of inherent
unique properties. Adsorbents and food
bio-additions based on them require a
regular check of quality. Spin Track NMR-analyzer
allows investigators to obtain
information about moisture,
crystallinity, purity and structure of
polysaccharides.
Porosity
of Rock Cores/Heterogeneous Catalysts/Zeolites
The possibility of oil development can
be defined more exactly in the initial
stages of exploration by using NMR.
Rock cores saturated by bitumen or water
provide information on degree of
saturation, structure of saturating
compounds, porosity, and diffusion
characteristics. This information allows
the prediction of oil production yields.
The Spin Track NMR-analyzer
with a 35mm probe gives the possibility
to obtain such information.
Scientific
applications
The spectrometer’s Relax software
allows construction of many types of NMR
pulse sequences, user-defined
interfaces, data processing (digital
experiments filtering, fitting, Fourier
and Laplace transforms) and data
manipulations. Thus, customers can
directly run automated standard type NMR
experiments just by “pressing one
button” in the program shell, or
create new applications using the
powerful pascal-like script language. Widely
used experiments like measurements of T1
and T2 (90-tau-90,
180-tau-90, CPMG,
FID, Spin Echo, Solid-Echo) are included
into the Relax software as default
examples. The NMR
measurements can be accompanied with the
high precision calibration samples and
built-in software calibration
procedures. Easy automatic tuning of the
NMR frequency,
pulse-durations, TX power and RX gain is
included into the software package.
Process NMR Associates Begins Marketing of Cutting Edge TD-NMR Spectrometer
Resonance Systems Ltd. has granted Process NMR Associates the rights to promote, market, and sell it’s NMR products and custom NMR hardware in the Americas, and Worldwide. The basic product of the company is a portable NMR-analyzer called Spin Track that can be used for many different low and high resolution NMR applications.
Spin Track meets the requirements of many relaxation and diffusion based NMR analyses:
Food
industry (Solid Fat Content Analysis,
Dairy Products, Oil and Moisture in
Chocolate, Powdered Milk, Cheese and
other food products; Oil and Moisture in
seeds, Emulsion Characteristics)
Lipid Analysis – Fatty Acid
Distribution
Cellulose and paper manufacturing
(Moisture/Crystallinity Analysis,
investigations of ageing effects)
Oil industry (rock cores analysis,
oil-water, oil-water-gas, viscosity,
physical property correlation, )
Polymer and rubber industry (Curing
degree and elasticity analysis, polymer
ageing, glass transition,
amorphous/crystalline content)
Chemical industry (Density, Melting
Points, Copolymer Ratios, Compatibility,
Cure, Cross Linking, H or F content,
Medicine (NMR Surface Analysis of
Patients, Plasma Analysis)
Environmental (Water Pollution, Forest
Degradation, Soils, Fertilizers)
Fibers – Moisture and Finish Content
Pharmaceuticals (Tablet Analysis,
Coatings/Components/Moisture,
Hydrogen/Fluorine/Sodium Content)
Relaxation, Diffusion, Particle Size,
Pore Size Distribution
Utilization of mobile NMR measurement equipment from Process NMR Associates provides the following advantages:
Reduction
of expenses associated with meeting
quality requirements of products
Simplicity of use in routine production
measurements and in advanced
laboratories for complicated analysis
Mobility of the hardware and low cost
for the overall device
Non-invasive measurements of any sample
Hardware solutions for non-standard NMR
applications
Permanent technical support and
comprehensive scientific consulting
Fair price and absolute ease of
operation!
Portable Low-Resolution NMR Analyzer
Analyzer is designed to perform:
All
standard NMR
applications
Development of new NMR-based
techniques
Teaching quantum physics, NMR,
analytical chemistry in Universities and
Colleges
NMR analyzer Spin Track comprises functional parts (probes, preamplifier and duplexer, TX Power Amplifier, Sequence Generator and PC Interface, Data Acquisition System, NMR Transceiver) which can be purchased separately and