E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Lignin for Energy, Chemicals and Materials"

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Natural Products".

Deadline for manuscript submissions: 31 January 2018

Special Issue Editors

Guest Editor
Prof. Dr. Charles Xu

Institute for Chemicals and Fuels from Alternative Resources (ICFAR), Department of Chemical and Biochemical Engineering, Western University, Ontario, Canada
Website | E-Mail
Phone: 519-661-2111 ext. 86414
Fax: 519-661-4016
Interests: Biorefining technologies; Bio-fuels; Bio-based chemicals; Bio-based materials; Thermochemical conversion; Hydrothermal liquefaction; Pyrolysis; Combustion; Gasification; Lignocellulosic biomass; Forestry residues; Agricultural residues; Sugars; Starch; Cellulose; Lignin; Municipal solid wastes; Wastewater sludge; Catalysis; Catalysts; Chemical reaction engineering; Green process engineering
Guest Editor
Dr. Michael Paleologou

Research Leader, Lignin Products, Biorefinery Program, FPInnovations, 570 boul. Saint-Jean, Pointe-Claire(QC) H9R 3J9, Canada
E-Mail
Interests: forest biorefinery; lignin recovery; lignin characterization; lignin products; hemicellulose recovery; hemicellulose products; methanol recovery; biomass processing operations; process integration and economics; black and red liquor characterization; chemical recovery; chemical separation and regeneration technologies for kraft, sulphite and BCTMP mills; system closure

Special Issue Information

Dear Colleagues,

Lignin is the second most abundant natural renewable polymer after cellulose. Natural lignin is a phenolic polymer of three monolignols with an amorphous macromolecular structure. Lignin is currently being produced in large quantities as a by-product of chemical pulping and cellulosic ethanol processes. According to the International Lignin Institute, about 40–50 million tonnes of kraft lignin (KL) are generated each year, globally, in the form of “black liquor”. While combustion of black liquor to regenerate pulping chemicals and to produce steam and power is an integral part of the kraft process, a small portion of the lignin can be removed without compromising mill material and energy balances. Meanwhile, the production of ethanol, butanol and platform chemicals (e.g., lactic, succinic and other organic acids) from cellulosic sugars is growing. For this to achieve extensive commercial success on a worldwide basis, value-added applications are needed for the hydrolysis lignin by-products that are generated from lignocellulose hydrolysis processes.

Many studies have been conducted on lignin utilization. Similar to other carbonaceous solid fuels, lignin can be a source for energy and fuels (e.g., combustion/co-combustion of lignin for energy, pyrolysis or hydrothermal liquefaction of lignin for bio-oils/liquid bio-fuels, or gasification of lignin for syngas/hydrogen, etc.). The presence of various functional groups (aromatic ring free positions and hydroxyl groups) on lignin structure, biodegradability, antioxidant, flame retardant and reinforcing capability make it as a potential candidate for the production of bio-aromatic chemicals (e.g., vanillin, phenols and antioxidants), bio-based polymeric materials (e.g., resins and polymers), and carbon fibers for use as reinforcement fillers in thermoplastic polymers, light-weight composite materials, as well as graphene for use in supercapacitors for energy storage. Direct use of lignin for chemical synthesis and materials can be challenging because the molecular weight is too high and because reactivity is reduced due to steric hindrance effects. The reactivity of lignin could be enhanced through some chemical modifications and thermochemical de-polymerization processes.

This Special Issue aims to cover recent progress and trends in the utilization of lignin or modified/de-polymerized lignin in chemical synthesis, materials and energy. Submissions are welcome but not limited to the topics listed below. Types of contributions to this Special Isssue can be full research articles, short communications, and reviews focusing on the utilization of lignin for energy/fuels, chemical and materials.

  • Extraction of lignin from pulping processes or cellulosic ethanol processes;
  • Chemical modification/de-polymerization of lignin;
  • Combustion/co-combustion of lignin for energy;
  • Pyrolysis or hydrothermal liquefaction of lignin for bio-oils/liquid bio-fuels;
  • Gasification of lignin for syngas/hydrogen;
  • Production of bio-aromatic chemicals from lignin (e.g., vanillin, phenols and antioxidants);
  • Synthesis of bio-based polymeric materials from lignin (e.g., resins and polymers)
  • Production of carbon fibers as reinforcement fillers in thermoplastic polymers or light-weight composite materials
  • Production of graphene for use in supercapacitors for energy storage.

Prof. Chunbao (Charles) Xu
Dr. Michael Paleologou
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Molecules is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1800 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Lignin
  • Chemical characterization
  • Chemical modification
  • De-polymerization
  • Combustion
  • Energy
  • Pyrolysis
  • Hydrothermal liquefaction
  • Bio-oils
  • Phenols
  • Bio-aromatic chemicals
  • Synthesis
  • Resins
  • Polymers
  • Carbon fibers
  • Composites
  • Graphene
  • Supercapacitors

Published Papers (2 papers)

View options order results:
result details:
Displaying articles 1-2
Export citation of selected articles as:

Research

Open AccessArticle Sustainable Bio-Based Phenol-Formaldehyde Resoles Using Hydrolytically Depolymerized Kraft Lignin
Molecules 2017, 22(11), 1850; doi:10.3390/molecules22111850
Received: 11 September 2017 / Revised: 26 October 2017 / Accepted: 27 October 2017 / Published: 28 October 2017
PDF Full-text (11454 KB) | HTML Full-text | XML Full-text
Abstract
In this study bio-based bio-phenol-formaldehyde (BPF) resoles were prepared using hydrolytically depolymerized Kraft lignin (DKL) as bio-phenol to partially substitute phenol. The effects of phenol substitution ratio, weight-average molecular weight (Mw) of DKL and formaldehyde-to-phenol (F/P) ratio were also investigated
[...] Read more.
In this study bio-based bio-phenol-formaldehyde (BPF) resoles were prepared using hydrolytically depolymerized Kraft lignin (DKL) as bio-phenol to partially substitute phenol. The effects of phenol substitution ratio, weight-average molecular weight (Mw) of DKL and formaldehyde-to-phenol (F/P) ratio were also investigated to find the optimum curing temperature for BPF resoles. The results indicated that DKL with Mw ~ 1200 g/mol provides a curing temperature of less than 180 °C for any substitution level, provided that F/P ratios are controlled. Incorporation of lignin reduced the curing temperature of the resin, however, higher Mw DKL negatively affected the curing process. For any level of lignin Mw, the curing temperature was found to increase with lower F/P ratios at lower phenol substitution levels. At 25% and 50% phenol substitution, increasing the F/P ratio allows for synthesis of resoles with lower curing temperatures. Increasing the phenol substitution from 50% to 75% allows for a broader range of lignin Mw to attain low curing temperatures. Full article
(This article belongs to the Special Issue Lignin for Energy, Chemicals and Materials)
Figures

Figure 1

Open AccessArticle Valorization of Lignin by Partial Wet Oxidation Using Sustainable Heteropoly Acid Catalysts
Molecules 2017, 22(10), 1625; doi:10.3390/molecules22101625
Received: 12 September 2017 / Revised: 25 September 2017 / Accepted: 27 September 2017 / Published: 28 September 2017
PDF Full-text (2138 KB) | HTML Full-text | XML Full-text
Abstract
The production of carboxylic acids by partial wet oxidation of alkali lignin at elevated temperatures and pressures was studied experimentally. Two different heteropoly acids, phosphotungstic acid (H3PW12O40) and phosphomolybdic acid (H3PMo12O40),
[...] Read more.
The production of carboxylic acids by partial wet oxidation of alkali lignin at elevated temperatures and pressures was studied experimentally. Two different heteropoly acids, phosphotungstic acid (H3PW12O40) and phosphomolybdic acid (H3PMo12O40), were used to catalyze the oxidation of lignin under hydrothermal conditions. Factors influencing the total yield of carboxylic acids formed during the partial oxidation of lignin were investigated. Formic, acetic and succinic acids were the major products identified. Of the two catalysts used, phosphomolybdic acid gave the most promising results, with carboxylic acid yields and lignin conversions of up to 45% and 95%, respectively. Full article
(This article belongs to the Special Issue Lignin for Energy, Chemicals and Materials)
Figures

Back to Top