Monitoring Molecular Weight Changes during Technical Lignin Depolymerization by Operando Attenuated Total Reflectance Infrared Spectroscopy and Chemometrics

Technical lignins are increasingly available at industrial scale, offering opportunities for valorization, such as by (partial) depolymerization. Any downstream lignin application requires careful tailoring of structural properties, such as molecular weight or functional group density, properties th...

Full description

Saved in:
Bibliographic Details
Published in:ChemSusChem Vol. 14; no. 24; pp. 5517 - 5524
Main Authors: Khalili, Khaled N. M., Peinder, Peter, Donkers, Jacqueline, Gosselink, Richard J. A., Bruijnincx, Pieter C. A., Weckhuysen, Bert M.
Format: Journal Article
Language:English
Published: Germany Wiley Subscription Services, Inc 17.12.2021
John Wiley and Sons Inc
Subjects:
ATR-IR spectroscopy
Chemometrics
Depolymerization
Functional groups
Infrared spectroscopy
Lignin
lignin valorization
Molecular weight
operando spectroscopy
Polydispersity
Reflectance
Reforming
Size exclusion chromatography
Spectrum analysis
ATR-IR spectroscopy
chemometrics
lignin valorization
size exclusion chromatography
operando spectroscopy
ISSN:1864-5631, 1864-564X, 1864-564X
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Technical lignins are increasingly available at industrial scale, offering opportunities for valorization, such as by (partial) depolymerization. Any downstream lignin application requires careful tailoring of structural properties, such as molecular weight or functional group density, properties that are difficult to control or predict given the structure variability and recalcitrance of technical lignins. Online insight into changes in molecular weight (Mw), to gauge the extent of lignin depolymerization and repolymerization, would be highly desired to improve such control, but cannot be readily provided by the standard ex‐situ techniques, such as size exclusion chromatography (SEC). Herein, operando attenuated total reflectance infrared (ATR‐IR) spectroscopy combined with chemometrics provided temporal changes in Mw during lignin depolymerization with high resolution. More specifically, ex‐situ SEC‐derived Mw and polydispersity data of kraft lignin subjected to aqueous phase reforming conditions could be well correlated with ATR‐IR spectra of the reaction mixture as a function of time. The developed method showed excellent regression results and relative error, comparable to the standard SEC method. The method developed has the potential to be translated to other lignin depolymerization processes. Weight watching: An operando attenuated total reflectance infrared (ATR‐IR) spectroscopy‐chemometrics method that correlates size exclusion chromatography‐derived molecular weight (Mw) and polydispersity (PD) measurements of a kraft lignin depolymerization process with the corresponding operando ATR‐IR spectra is developed. The approach is demonstrated here for aqueous phase reforming of kraft lignin but is anticipated to be applicable more generally to various lignin depolymerization processes in biorefinery to provide information of Mw of lignin in real time.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
content type line 23
ISSN:1864-5631
1864-564X
1864-564X
DOI:10.1002/cssc.202101853