Column screening for the separation of lignin-related phenolic compounds in lignosulfonate lignin using ultra-high-performance supercritical fluid chromatography
(2020) KEML10 20201Mathematical Statistics
Department of Chemistry
- Abstract
- Introduction: This study attempts to optimize the choice of stationary phase for the separation of lignosulfonate lignin compounds using supercritical fluid chromatography coupled to mass spectrometry.
Background: Lignin is a potential renewable source of phenolic compounds. Lignosulfonate lignins are produced during pulping processes producing very complex mixtures, which are challenging to analyze.
Aim(s): This study aims to optimize the separation of lignin-related phenolic compounds in a lignosulfonate lignin sample using resolution-level graphs. A second aim is the investigation of retention behavior of monomeric and dimeric compounds for a number of UHPSFC/MS methods with varying choice of stationary phase and elution gradient.... (More) - Introduction: This study attempts to optimize the choice of stationary phase for the separation of lignosulfonate lignin compounds using supercritical fluid chromatography coupled to mass spectrometry.
Background: Lignin is a potential renewable source of phenolic compounds. Lignosulfonate lignins are produced during pulping processes producing very complex mixtures, which are challenging to analyze.
Aim(s): This study aims to optimize the separation of lignin-related phenolic compounds in a lignosulfonate lignin sample using resolution-level graphs. A second aim is the investigation of retention behavior of monomeric and dimeric compounds for a number of UHPSFC/MS methods with varying choice of stationary phase and elution gradient.
Methods: In order to improve the chromatographic resolution six different columns (1-AA, 2-PIC, DEA, DIOL, and FP) and multiple gradients for each column were compared. The gradients were different binary mixtures of methanol and supercritical carbon dioxide. Performance of each column was quantified by comparing the number of peaks that could be resolved for each combination of column and gradient using resolution-level graphs.
Results: Quantifying separation as the number of peak pairs with a resolution of 1.5 or higher, the best separation was achieved using either a 1-AA, 2-PIC or DEA column. When investigating the retention behavior of monomers and dimers, these two groups are best separated using the 1-AA column. Some monomeric compounds have relatively high retention times on the DEA column, this is possibly because they are acidic.
Conclusion: Comparing resolution-level graphs and the number of peak pairs with a resolution of 1.5 or higher, 1-AA, 2-PIC and DEA stationary phases all work well for the separation of phenolic compounds in lignosulfonate. The 1-AA column separates monomeric and dimeric compounds well while many acidic compounds have high retention on the DEA column. (Less) - Popular Abstract
- When doing chemical analysis, of everything from animal products to novel materials, it is often necessary to separate compounds in complex samples using so-called chromatography. In chromatography the separation of compounds is based on their interactions with a solvent and a so-called stationary phase. This is often done using organic solvents that are harmful to both the environment and the user. A modern technique which is sometimes able to replace such substances as solvent is supercritical fluid chromatography.
When a liquid is exposed to a certain combination of high temperatures and high pressure it reaches its critical point, where the border between liquid and gas phase become less distinct. Supercritical fluids often act... (More) - When doing chemical analysis, of everything from animal products to novel materials, it is often necessary to separate compounds in complex samples using so-called chromatography. In chromatography the separation of compounds is based on their interactions with a solvent and a so-called stationary phase. This is often done using organic solvents that are harmful to both the environment and the user. A modern technique which is sometimes able to replace such substances as solvent is supercritical fluid chromatography.
When a liquid is exposed to a certain combination of high temperatures and high pressure it reaches its critical point, where the border between liquid and gas phase become less distinct. Supercritical fluids often act remarkably different from the same substance in the liquid state, having gas-like viscosity but liquid-like density.
The most popular solvent for supercritical fluid chromatography today is not water but carbon dioxide, which is basically harmless to the user and is considered environmentally sustainable since it is a recycled industrial biproduct. Supercritical carbon dioxide is also a solvent which can be used for dissolving a wide range of different compounds.
The investigated material in this study is lignosulfonate lignin, which is also directly related to environmental issues. Lignin is a material which constitutes a large portion of the biomass. Even though it has many interesting chemical properties and is renewable, its commercial use is still not developed. Lignin is produced in many forms by the paper pulping industry. However, only 2% of the 70 million tons of lignin produced globally every year are used for chemical purposes, the rest is being wasted or, at best, burnt as fuel.
The lignosulfonate lignin mixtures produced are very complex, but may contain valuable compounds, such as vanillin, which is used as artificial vanilla flavor. However, the different compounds in the lignosulfonate lignin need to be separated from each other before any of them can be analyzed in detail. This study attempts to optimize an SFC method for this separation by comparing six different stationary phases. The stationary phases which achieved the best separation in this study were 1-aminoanthracene, 2-picolylamine and diethylamine. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9020990
- author
- Palmer, Simon LU
- supervisor
- organization
- course
- KEML10 20201
- year
- 2020
- type
- M2 - Bachelor Degree
- subject
- keywords
- Column screening, Green solvents, Lignosulfonate lignin, Resolution level graph, Supercritical fluid chromatography, Analytical chemistry, Analytisk kemi
- language
- English
- id
- 9020990
- date added to LUP
- 2020-06-26 08:46:23
- date last changed
- 2020-06-26 08:46:23
@misc{9020990,
abstract = {{Introduction: This study attempts to optimize the choice of stationary phase for the separation of lignosulfonate lignin compounds using supercritical fluid chromatography coupled to mass spectrometry.
Background: Lignin is a potential renewable source of phenolic compounds. Lignosulfonate lignins are produced during pulping processes producing very complex mixtures, which are challenging to analyze.
Aim(s): This study aims to optimize the separation of lignin-related phenolic compounds in a lignosulfonate lignin sample using resolution-level graphs. A second aim is the investigation of retention behavior of monomeric and dimeric compounds for a number of UHPSFC/MS methods with varying choice of stationary phase and elution gradient.
Methods: In order to improve the chromatographic resolution six different columns (1-AA, 2-PIC, DEA, DIOL, and FP) and multiple gradients for each column were compared. The gradients were different binary mixtures of methanol and supercritical carbon dioxide. Performance of each column was quantified by comparing the number of peaks that could be resolved for each combination of column and gradient using resolution-level graphs.
Results: Quantifying separation as the number of peak pairs with a resolution of 1.5 or higher, the best separation was achieved using either a 1-AA, 2-PIC or DEA column. When investigating the retention behavior of monomers and dimers, these two groups are best separated using the 1-AA column. Some monomeric compounds have relatively high retention times on the DEA column, this is possibly because they are acidic.
Conclusion: Comparing resolution-level graphs and the number of peak pairs with a resolution of 1.5 or higher, 1-AA, 2-PIC and DEA stationary phases all work well for the separation of phenolic compounds in lignosulfonate. The 1-AA column separates monomeric and dimeric compounds well while many acidic compounds have high retention on the DEA column.}},
author = {{Palmer, Simon}},
language = {{eng}},
note = {{Student Paper}},
title = {{Column screening for the separation of lignin-related phenolic compounds in lignosulfonate lignin using ultra-high-performance supercritical fluid chromatography}},
year = {{2020}},
}