Submit to Molecules Review for Molecules Propose a Special Issue

Journal Menu

Journal Browser

► Journal Browser

A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry"

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Published Papers

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

Deadline for manuscript submissions: closed (31 May 2022) | Viewed by 16304

Share This Special Issue

Special Issue Editors

Prof. Dr. Mara G. Freire

E-Mail Website
Guest Editor

CICECO - Aveiro Institute of Materials, Chemistry Department, University of Aveiro, Aveiro, Portugal
Interests: separation processes; ionic liquids; deep eutectic solvents; (bio)pharmaceuticals; biomarkers; purification; stability
Special Issues, Collections and Topics in MDPI journals

Dr. Paula Berton

E-Mail Website
Guest Editor

Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, AB, Canada
Interests: ionic liquids; sustainability; separations; biomass; unconventional oil
Special Issues, Collections and Topics in MDPI journals

Dr. Jorge F. B. Pereira

E-Mail Website
Guest Editor

Department of Chemical Engineering, CIEPQPF, University of Coimbra, Coimbra, Portugal
Interests: Ionic liquids; bioprocessing; proteins; enzymes; stability; downstream
Special Issues, Collections and Topics in MDPI journals

Dr. Hui Wang

E-Mail Website
Guest Editor

Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
Interests: ionic liquids; green catalysis; natural product separation

Dr. Xingmei Lu

E-Mail Website
Guest Editor

Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
Interests: ionic liquids

Special Issue Information

Dear Colleagues,

In recent decades, we have witnessed a change in the meaning of “chemistry”. In the beginning, terms such as organic, inorganic, and analytical were the ones most commonly used to subdivide this fundamental discipline. However, during the 1990s, awareness regarding the environmental impacts of traditional chemistry changed the way we see it and apply it. The term “green chemistry”, defined as the “design of chemical products and processes to reduce or eliminate the use and generation of hazardous substances” (by Paul T. Anastas), arose as a landmark in chemistry. Since then, a “greener wave” has grown in the Scientific Community, fully transforming this discipline, with the protection of the environment and people, as well as the enhancement of competitiveness of chemical industries in ecologic, economic, and sustainable aspects, appearing as critical challenges.

The worldwide scientific community working in chemistry is devoting strong efforts to fitting within green chemistry and overcoming these challenges. Among world-renowned researchers, Prof. Dr. Robin D. Rogers is one of the pioneers in “greening” chemistry. During his outstanding scientific career, he has brought sustainability into diverse chemistry-related applications. Among his remarkable research contributions, one notable achievement is the use of ionic liquids and green chemistry for developing sustainable chemical technologies in the fields of materials, separations, energy, and medicine. He is an inspiration for younger researchers, always supporting and challenging them to go deeper and contribute toward sustainable development in benefit of society.

We believe that this is the right moment to honor his remarkable “Scientific Journey within Green Chemistry”, as well as to acknowledge his collaboration and strong support in developing our scientific careers. Therefore, it is our great pleasure to invite all of you to submit your research or review manuscript to this Special Issue. This Special Issue aims to cover research in all fields that Prof. Dr. Robin D. Rogers has been working in, with special focus on “green chemistry”.

Prof. Dr. Mara G. Freire
Dr. Paula Berton
Prof. Dr. Jorge F. B. Pereira
Dr. Hui Wang
Dr. Xingmei Lu
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 submissions that pass pre-check are 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 semimonthly 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 2700 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

green chemistry
ionic liquids
materials
energy
separations
medicine
sustainability

Published Papers (7 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Research

Jump to: Review

15 pages, 5451 KiB

Open AccessArticle

Renewable Schiff-Base Ionic Liquids for Lignocellulosic Biomass Pretreatment

by Hemant Choudhary, Venkataramana R. Pidatala, Mood Mohan, Blake A. Simmons, John M. Gladden and Seema Singh

Molecules 2022, 27(19), 6278; https://doi.org/10.3390/molecules27196278 - 23 Sep 2022

Cited by 1 | Viewed by 1392

Abstract

Growing interest in sustainable sources of chemicals and energy from renewable and reliable sources has stimulated the design and synthesis of renewable Schiff-base (iminium) ionic liquids (ILs) to replace fossil-derived ILs. In this study, we report on the synthesis of three unique iminium-acetate ILs from lignin-derived aldehyde for a sustainable “future” lignocellulosic biorefinery. The synthesized ILs contained only imines or imines along with amines in their structure; the ILs with only imines group exhibited better pretreatment efficacy, achieving >89% sugar release. Various analytical and computational tools were employed to understand the pretreatment efficacy of these ILs. This is the first study to demonstrate the ease of synthesis of these renewable ILs, and therefore, opens the door for a new class of “Schiff-base ILs” for further investigation that could also be designed to be task specific. Full article

(This article belongs to the Special Issue A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry")

► Show Figures

Figure 1

9 pages, 1360 KiB

Open AccessArticle

1-Propyl-4(5)-Methylimidazole Isomers for Temperature Swing Solvent Extraction

by Shuai Qian, Lauren M. Ward, Luke S. Rakers, Steven T. Weinman and Jason E. Bara

Molecules 2022, 27(17), 5583; https://doi.org/10.3390/molecules27175583 - 30 Aug 2022

Viewed by 1697

Abstract

Temperature swing solvent extraction (TSSE) utilizes an amine solvent with temperature-dependent water solubility to dissolve water at a lower temperature to concentrate or crystallize the brine and the phases are separated. Then, the water in solvent mixture is heated to reduce water solubility and cause phase separation between the solvent and water. The solvent and de-salted water phases are separated, and the regenerated solvent can be recycled. Issues with current TSSE solvents include the high solvent in water solubility and the high solvent volatility. This project used the highly tunable platform molecule imidazole to create two 1-butylimidazole isomers, specifically 1-propyl-4(5)-methylimidazole, to test their effectiveness for TSSE. The imidazoles take in more water than their current state-of-the-art counterparts, but do not desalinate the product water and dissolve in water at higher concentrations. Thus, while imidazoles make intriguing candidates for TSSE, further work is needed to understand how to design imidazoles that will be useful for TSSE applications. Full article

(This article belongs to the Special Issue A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry")

► Show Figures

Figure 1

14 pages, 1793 KiB

Open AccessCommunication

Deproteinization of Chitin Extracted with the Help of Ionic Liquids

by Douglas R. Lyon, Jr., Bryan R. Smith, Noureddine Abidi and Julia L. Shamshina

Molecules 2022, 27(13), 3983; https://doi.org/10.3390/molecules27133983 - 21 Jun 2022

Cited by 3 | Viewed by 1465

Abstract

The isolation of chitin utilizing ionic liquid 1-ethyl-3-methylimidazolium acetate has been determined to result in polymer contaminated with proteins. For the first time, the proteins in chitin extracted with ionic liquid have been quantified; the protein content was found to vary from 1.3 to 1.9% of the total weight. These proteins were identified and include allergenic proteins such as tropomyosin. In order to avoid ‘traditional’ hydroxide-based deproteinization of chitin, which could reduce the molecular weight of the final product, alternative deproteinization strategies were attempted. Testing of the previously reported deproteinization method using aqueous K₃PO₄ resulted in protein reduction by factors varying from 2 to 10, but resulted in significant phosphate salt contamination of the final product. Contrarily, the incorporation of GRAS (Generally Recognized as Safe) compound Polysorbate 80 into the polymer washing step provided the polymer of comparable purity with no contaminants. This study presents new options for the deproteinization of chitin that can replace traditional approaches with methods that are environmentally friendly and can produce high purity polymer. Full article

(This article belongs to the Special Issue A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry")

► Show Figures

Graphical abstract

14 pages, 2225 KiB

Open AccessArticle

A Combined Deep Eutectic Solvent–Ionic Liquid Process for the Extraction and Separation of Platinum Group Metals (Pt, Pd, Rh)

by Olga Lanaridi, Sonja Platzer, Winfried Nischkauer, Andreas Limbeck, Michael Schnürch and Katharina Bica-Schröder

Molecules 2021, 26(23), 7204; https://doi.org/10.3390/molecules26237204 - 27 Nov 2021

Cited by 8 | Viewed by 2259

Abstract

Recovery of platinum group metals from spent materials is becoming increasingly relevant due to the high value of these metals and their progressive depletion. In recent years, there is an increased interest in developing alternative and more environmentally benign processes for the recovery of platinum group metals, in line with the increased focus on a sustainable future. To this end, ionic liquids are increasingly investigated as promising candidates that can replace state-of-the-art approaches. Specifically, phosphonium-based ionic liquids have been extensively investigated for the extraction and separation of platinum group metals. In this paper, we present the extraction capacity of several phosphonium-based ionic liquids for platinum group metals from model deep eutectic solvent-based acidic solutions. The most promising candidates, P₆₆₆₁₄Cl and P₆₆₆₁₄B2EHP, which exhibited the ability to extract Pt, Pd, and Rh quantitively from a mixed model solution, were additionally evaluated for their capacity to recover these metals from a spent car catalyst previously leached into a choline-based deep eutectic solvent. Specifically, P₆₆₆₁₄Cl afforded extraction of the three target precious metals from the leachate, while their partial separation from the interfering Al was also achieved since a significant amount (approx. 80%) remained in the leachate. Full article

(This article belongs to the Special Issue A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry")

► Show Figures

Graphical abstract

18 pages, 2538 KiB

Open AccessArticle

Synthesis of Purine-Based Ionic Liquids and Their Applications

by Ana R. F. Carreira, Telma Veloso, Nicolas Schaeffer, Joana L. Pereira, Sónia P. M. Ventura, Cécile Rizzi, Juliette Sirieix Plénet, Helena Passos and João A. P. Coutinho

Molecules 2021, 26(22), 6958; https://doi.org/10.3390/molecules26226958 - 18 Nov 2021

Cited by 4 | Viewed by 3040

Abstract

Bio-based ionic liquids (ILs) are being increasingly sought after, as they are more sustainable and eco-friendly. Purines are the most widely distributed, naturally occurring N-heterocycles, but their low water-solubility limits their application. In this work, four purines (theobromine, theophylline, xanthine, and uric acid) were combined with the cation tetrabutylammonium to synthesize bio-based ILs. The physico–chemical properties of the purine-based ILs were characterized, including their melting and decomposition temperatures and water-solubility. The ecotoxicity against the microalgae Raphidocelis subcapitata was also determined. The ILs show good thermal stability (>457 K) and an aqueous solubility enhancement ranging from 53- to 870-fold, in comparison to their respective purine percursors, unlocking new prospects for their application where aqueous solutions are demanded. The ecotoxicity of these ILs seems to be dominated by the cation, and it is similar to chloride-based IL, emphasizing that the use of natural anions does not necessarily translate to more benign ILs. The application of the novel ILs in the formation of aqueous biphasic systems (ABS), and as solubility enhancers, was also evaluated. The ILs were able to form ABS with sodium sulfate and tripotassium citrate salts. The development of thermoresponsive ABS, using sodium sulfate as a salting-out agent, was accomplished, with the ILs having different thermosensitivities. In addition, the purine-based ILs acted as solubility enhancers of ferulic acid in aqueous solution. Full article

(This article belongs to the Special Issue A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry")

► Show Figures

Graphical abstract

Review

Jump to: Research

44 pages, 5425 KiB

Open AccessReview

Shaking Things from the Ground-Up: A Systematic Overview of the Mechanochemistry of Hard and High-Melting Inorganic Materials

by Thomas Auvray and Tomislav Friščić

Molecules 2023, 28(2), 897; https://doi.org/10.3390/molecules28020897 - 16 Jan 2023

Cited by 8 | Viewed by 3107

Abstract

We provide a systematic overview of the mechanochemical reactions of inorganic solids, notably simple binary compounds, such as oxides, nitrides, carbides, sulphides, phosphides, hydrides, borides, borane derivatives, and related systems. Whereas the solid state has been traditionally considered to be of little synthetic value by the broader community of synthetic chemists, the solid-state community, and in particular researchers focusing on the reactions of inorganic materials, have thrived in building a rich and dynamic research field based on mechanically-driven transformations of inorganic substances typically seen as inert and high-melting. This review provides an insight into the chemical richness of such mechanochemical reactions and, at the same time, offers their tentative categorisation based on transformation type, resulting in seven distinct groupings: (i) the formation of adducts, (ii) the reactions of dehydration; (iii) oxidation–reduction (redox) reactions; (iv) metathesis (or exchange) reactions; (v) doping and structural rearrangements, including reactions involving the reaction vessel (the milling jar); (vi) acid–base reactions, and (vii) other, mixed type reactions. At the same time, we offer a parallel description of inorganic mechanochemical reactions depending on the reaction conditions, as those that: (i) take place under mild conditions (e.g., manual grinding using a mortar and a pestle); (ii) proceed gradually under mechanical milling; (iii) are self-sustained and initiated by mechanical milling, i.e., mechanically induced self-propagating reactions (MSRs); and (iv) proceed only via harsh grinding and are a result of chemical reactivity under strongly non-equilibrium conditions. By elaborating on typical examples and general principles in the mechanochemistry of hard and high-melting substances, this review provides a suitable complement to the existing literature, focusing on the properties and mechanochemical reactions of inorganic solids, such as nanomaterials and catalysts. Full article

(This article belongs to the Special Issue A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry")

► Show Figures

Figure 1

14 pages, 1170 KiB

Open AccessReview

Deep Eutectic Solvents: Alternative Solvents for Biomass-Based Waste Valorization

by Giovanni P. Rachiero, Paula Berton and Julia Shamshina

Molecules 2022, 27(19), 6606; https://doi.org/10.3390/molecules27196606 - 05 Oct 2022

Cited by 10 | Viewed by 2104

Abstract

Innovative technologies can transform what are now considered “waste streams” into feedstocks for a range of products. Indeed, the use of biomass as a source of biopolymers and chemicals currently has a consolidated economic dimension, with well-developed and regulated markets, in which the evaluation of the manufacturing processes relies on specific criteria such as purity and yield, and respects defined regulatory parameters for the process safety. In this context, ionic liquids and deep eutectic solvents have been proposed as environmentally friendly solvents for applications related to biomass waste valorization. This mini-review draws attention to some recent advancements in the use of a series of new-solvent technologies, with an emphasis on deep eutectic solvents (DESs) as key players in the development of new processes for biomass waste valorization. This work aims to highlight the role and importance of DESs in the following three strategic areas: chitin recovery from biomass and isolation of valuable chemicals and biofuels from biomass waste streams. Full article

(This article belongs to the Special Issue A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry")

► Show Figures

Journal Menu

Journal Browser

A Themed Issue in Honor of Professor Robin D. Rogers - "A Scientific Journey within Green Chemistry"

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (7 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI