Green Solvent Research Articles

Heavy oil SARA components interaction with p,o,m-xylene solvents/ionic liquids-molecular dynamics simulation and experiment

Oily sludge is generally produced in the process of oil extraction, refining, storage and transportation and disposal of oily wastewater. Is mixed with crude oil, all kinds of refined oil and residual oil and other heavy oil sludge. The main components of heavy oil are saturated fraction, aromatic fraction, colloid and asphaltene which are difficult to treat in oily sludge. In the treatment of oil-containing sludge is usually used solvent extraction method, but due to the high price of extractant, low recycling rate process is a relatively long, complex process, with high treatment costs. Therefore, it is important to find an efficient and cheap extraction solvent. And ionic liquids as inexpensive, environmentally friendly, strengthen the oil-solid separation effect of green solvents, in the auxiliary oil sludge separation on the research has attracted wide attention. In this paper, through molecular dynamics simulation, the diffusion behavior of the four components of heavy oil under different solvents was simulated by using Material Studio software, and the mean square displacement (MSD) was used to describe the diffusion characteristics of the four components of heavy oil under different solvent systems, and the interactions of the four components of heavy oil under different solvents were analyzed in a microscopic point of view. The results showed that the diffusion coefficients of the four components of heavy oil were large and the diffusion rate was fast in the xylene system, while the diffusion coefficients of the four components of heavy oil were small and the diffusion rate was slow in the ionic liquid system.

Supercritical CO2 green solvent extraction of Nepeta crispa: Evaluation of process optimization, chemical analysis, and biological activity

This research investigates the extraction of compounds from Nepeta crispa (N. crispa), utilizing supercritical carbon dioxide green solvent, for the first time. Using RSM, the study examines the impact of pressure (15–25 MPa), temperature (313–333 K), and co-solvent (0.5–3.5%) on the extraction yield. The antioxidant activity of the essential oil is assessed through Ferric Reducing Antioxidant Power (FRAP) assay, while its antibacterial properties are evaluated against four bacterial strains. The SCFE method achieved a maximum yield of 1.812 % at optimum conditions (P= 25 MPa, T= 313 K and co-solvent= 3.5%). GC-Mass analysis revealed that the primary constituents of N. crispa essential oil which are 1,8-cineol and 4aα,7α,7aα-nepetalactone in both extraction methods. The antioxidant and antibacterial results of N. crispa showed the superiority of SC-CO2 over hydrodistillation method. These observed antioxidant and antibacterial attributes highlight the plant’s potential suitability for applications within the food and pharmaceutical industries.

In-situ understanding on the formation of fibrillar morphology in green solvent processed all-polymer solar cells.

Solid additive engineering has been intensively explored on morphology tuning for highly efficient all-polymer solar cells (all-PSCs), a promising photovoltaic technology towards multi-scenario application. Although the nano-fibrillar network of the active layer induced by additive treatment is confirmed as the key factor for power conversion efficiency (PCE) of all-PSCs, its formation mechanism is not clearly revealed, for lack of precise and convincing real-time observation of crystallization and phase separation during the liquid-to-solid transition process of spin-coating. Herein we report an in-situ grazing incidence wide-angle/small-angle X-ray scattering (GIWAXS/GISAXS) screening that reveals the fact that naphthalene derived solid additives can suppress the aggregation of the polymer acceptor (PY-IT) at the beginning stage of spin coating, which provides sufficient time and space for the polymer donor (PM6) to form the fibril structure. Moreover, guided by this knowledge, a ternary all-polymer system is proposed, which achieves cutting-edge level PCEs for both small-area (0.04cm2) (also decent operational stability) and large-area (1cm2) devices.

Fractionation of Kraft Lignin for Production of Alkyd Resins for Biobased Coatings with Oxidized Lignin Dispersants as a Co-Product.

A new valorization pathway based on solvent fractionation was applied to kraft lignin, a major by-stream of the pulping industry, to extract a soluble lignin intermediate featuring an improved structural homogeneity, a low molecular weight, and a high content of phenolic hydroxyl and carboxylic acid groups to serve as a substitute of the nonrenewable polyacids in the formulation of alkyd resins, a dominant material used in the production of anticorrosion surface coatings. Herein, softwood kraft lignin was mixed in a low-cost green solvent, aqueous ethanol, prepared at different ratios, at room temperature to generate a soluble fraction of a low M w of ≤2200 g mol-1 and an insoluble fraction of a high M w of ≥3950 g mol-1 of lignin. The best combination of yields and molecular weights of soluble lignin (16-36% yield, 1740-1890 g mol-1) was attained using 50-80 vol % ethanol in fractionation. Thus, these conditions were further employed at the pilot scale to demonstrate the scalability of this technology. Soluble lignin from pilot fractionation was used to produce an optimal alkyd resin formulation and thereafter an anticorrosion coating on the metal surface, both of which matched the target properties of industrial standards well (180 s Persoz hardness and 72 gloss units of coating, 100% adhesion of paint with no cracks or peeling in the cross-cut test, no corrosion after 120 h of the salt spray test). The insoluble solids from pilot fractionation could also be valorized by alkali-O2 oxidation into lignin-based dispersants for special carbon black pigments. Overall, this study presents a new, simple strategy to develop an efficient, scalable, low-cost, and green process for upgrading kraft lignin into phenolic intermediates for biobased alkyd resins to facilitate sustainable production of high-performance anticorrosion coatings.

Green low-melting mixture solvents/ionic liquids-based carbon materials and lithium-ion batteries recycling leachate unexpectedly cause water pollution from dissolved organic matter

Low-melting mixture solvents (LoMMSs) and ionic liquids (ILs) are regarded as green solvents for the recovery of lithium-ion batteries (LIBs) cathode with high sustainability. Unexpectedly, we find for the first time that the release of LoMMSs- or ILs-based carbon materials and LIBs recycling leachate into water can lead to significant pollution from dissolved organic matter (DOM). Moreover, COD, NH4–N and total P concentration in river from Jingjinji Region is relatively high due to the high concentration of DOM. This work would provide us a hint that the application of so-called green LoMMSs and ILs in materials preparation and LIBs recovery should be treated with high caution in order to minimize DOM pollution for the rivers in Jingjinji Region.

Dairy Chain Safety in the Context of Antibiotic Residues-Current Status of Confirmatory Liquid Chromatography Methods: A Review.

With ever-developing analytical capabilities, the protection of the dairy chain from contamination by residues of veterinary drugs is improving. Legislative requirements are an inherent part of this process. Of antibiotics in dairy farming, representatives of the beta-lactams, tetracyclines, sulfonamides, (fluoro)quinolones, aminoglycosides, or polypeptide antibiotics are the most widely used. Due to the typically low levels of antibiotic residues in milk, mass spectrometry is the most commonly used detection technique. However, the interference of the sample matrix is one of its main limiting factors, and therefore, it needs to be eliminated. In the first step, the lipid fraction is removed and proteins are precipitated, followed by solid-phase or liquid-liquid extraction. The current trends include the reduction in the consumption of organic solvents (to reduce occupational hazards and burden to the environment) and automation, eliminating the influence of human error and optimizing the workflow. These trends lead to the development of new microextraction and automated techniques as well as the use of new sorbents and/or (green) solvents of natural origin. To capture the latest developments in the field and the relatively recent aforementioned trends, this review focuses on papers investigating antimicrobial residues in milk that were published between 2015 and 2024, providing an overview of emerging techniques applicable to antibiotic residue detection in milk samples.

A Comprehensive Review on Imperative Role of Ionic Liquids in Pharmaceutical Sciences.

Ionic liquids (ILs) are poorly-coordinated ionic salts that can exist as a liquid at room temperatures (or <100 °C). ILs are also referred to as "designer solvents" because so many of them have been created to solve particular synthetic issues. ILs are regarded as "green solvents" because they have several distinctive qualities, including better ionic conduction, recyclability, improved solvation ability, low volatility, and thermal stability. These have been at the forefront of the most innovative fields of science and technology during the past few years. ILs may be employed in new drug formulation development and drug design in the field of pharmacy for various functions such as improvement of solubility, targeted drug delivery, stabilizer, permeability enhancer, or improvement of bioavailability in the development of pharmaceutical or vaccine dosage formulations. Ionic liquids have become a key component in various areas such as synthetic and catalytic chemistry, extraction, analytics, biotechnology, etc., due to their superior abilities along with highly modifiable potential. This study concentrates on the usage of ILs in various pharmaceutical applications enlisting their numerous purposes from the delivery of drugs to pharmaceutical synthesis. To better comprehend cuttingedge technologies in IL-based drug delivery systems, highly focused mechanistic studies regarding the synthesis/preparation of ILs and their biocompatibility along with the ecotoxicological and biological effects need to be studied. The use of IL techniques can address key issues regarding pharmaceutical preparations such as lower solubility and bioavailability which plays a key role in the lack of effectiveness of significant commercially available drugs.

Synthesis of ZnTe powders from green solvents by a solvothermal method. Study of the sensing properties in a CO atmosphere

In this work, the characterization and testing of sensing properties of ZnTe powders for detecting carbon monoxide were investigated. The ZnTe synthesis was reached by a solvothermal process, using three different green solvents, methanol, ethanol, and isopropanol. The structural, morphological, and compositional properties of ZnTe powders were analyzed by X-ray diffraction, XRD, scanning electron microscopy, SEM, and atomic force microscopy, AFM, and X-ray energy dispersion (EDS), respectively. XRD confirmed the zincblende-type cubic phase of ZnTe, with crystallite sizes of the order of 69 nm. SEM images of all synthesized samples showed a surface covered with particles of different sizes and irregular morphologies. Finally, the sensing response of ZnTe samples to CO was measured for concentrations varying from 1 to 500 ppm at different operating temperatures, 100, 200, and 300 °C. The highest sensitivity, 18.4, was obtained for ZnTe samples synthesized from isopropanol as solvent, so ZnTe powders showed a good response for CO detection, resulting these materials promising to be applied as gas sensors.

Sulfamic Acid Catalyzed One‐Pot Three‐Component Synthesis of Spiro‐Oxindole Fused Dihydroquinazolinone Derivatives in Aqueous Medium

AbstractA simple, efficient, and straightforward protocol has been developed for the synthesis of spiro‐oxindole fused dihydroquinazolinone derivatives from one‐pot three‐component reactions of isatoic anhydride, various primary anilines, and substituted isatins using a catalytic amount of sulfamic acid as an organocatalyst in water under refluxed conditions. All the synthesized compounds were formed within just 2 h and isolated pure by simple filtration with excellent yields (89%–94%). Gram scale production, use of commercially available low‐cost organocatalyst, green solvent, reusability of the medium, one‐pot three‐component reaction strategy, no column chromatography, and high atom economy are some of the major benefits of this newly developed protocol.

Exploring chemical properties of essential oils from citrus peels using green solvent

The research explored the chemical characteristics of essential oils (EOs) extracted from the peels of four citrus fruits grown in northeastern Peru (lime, sweet lemon, mandarin and orange). The essential oils were extracted by hydrodistillation using a green solvent, and subsequently, their physicochemical profile, bioactive, heat capacity, and RAMAN mapping were determined; in addition, the volatile composition was determined by gas chromatography (GC-MS), and the main phenols by liquid chromatography (UHPLC). The results evidenced that sweet lemon and mandarin essential oils had higher antioxidant activity (1592.38 and 1216.13 μmol TE/g) and total phenolic content (680.78 and 420.28 mg GAE/g). In contrast, sweet lemon peel essential oil had the highest total flavonoid content (23.18 mg QE/g). D-limonene was the most abundant aromatic compound in orange (>67 %), mandarin (>70 %), and sweet lemon (>72 %) EOs; however, in the lime, it was the lowest (37 %). The most abundant component was the cyclobutane, 1,2-bis(1-methylethylethylenyl)-, trans- (32 %).

β‐Cyclodextrin‐SO3H as a Supramolecular Catalyst for Efficient Greener Synthesis of Substituted Bis(6‐aminouracil‐5‐yl)methanes in Water

AbstractA simple, straightforward, and highly efficient greener approach for synthesizing bis(6‐aminouracil‐5‐yl)methane derivatives was developed by employing β‐cyclodextrin‐SO3H as supramolecular catalyst in water at 100 °C. A total of 16 bis(6‐aminouracil‐5‐yl)methanes were synthesized via a one‐pot reaction between substituted aromatic aldehydes, 6‐amino‐1,3‐dimethyluracil, and 10% β‐cyclodextrin‐SO3H in water with 84%–92% yield within 20–120 min. The salient features of this protocol included water as green solvent, β‐cyclodextrin‐SO3H as recyclable supramolecular catalyst, mild reaction conditions, easy isolation of pure products, and good to excellent yields.

Ionic Liquid-Based Green Solvents for Extraction and Purification of Natural Plant Products

Introduction: This research paper explores the environmental sustainability of ionic liquid-based green solvents in the extraction and purification of natural plant products, with a focus on their entire life cycle. The objectives of the study were to assess the environmental impact of ionic liquid synthesis, energy consumption, water usage, emissions, recycling rates, policy effects, and stakeholder perceptions. Methods: Methodologically, we conducted a comprehensive Life Cycle Assessment (LCA) that involved primary data collection through field surveys and interviews with key stakeholders in the ionic liquid production and usage industry across various regions in India. The data were analyzed using specialized LCA software tools to quantify environmental impacts. Key findings include the identification of synthesis as a major contributor to environmental impact, emphasizing the need for greener synthesis methods. Results: The study revealed the significant carbon footprint, energy consumption, and water usage during production, highlighting opportunities for improvement. Emissions data underscored the importance of emission control measures, particularly for greenhouse gases and volatile organic compounds. Recycling and reuse were identified as environmentally friendly disposal methods. Policy compliance varied among stakeholders, indicating room for stricter regulations. Stakeholder perceptions varied, with researchers having the most positive outlook. Implications of the findings extend to sustainable chemistry practices, emphasizing interdisciplinary collaboration and the importance of considering the entire life cycle of chemical processes. Conclusion: This research contributes to a deeper understanding of green solvents and provides a foundation for promoting sustainable practices in industrial processes in India and globally.

Grafting of cinchonine onto rice husk nanosilica and its potential application in the synthesis of 2‐arylideneindan‐1,3‐diones and 2‐arylidene-5,5-dimethyl-1,3-cyclohexanedione

In this study, an eco-friendly and green procedure for Knoevenagel condensation reaction of aromatic aldehydes with indan-1,3-dione and dimedone was reported utilizing a rice husk silica‐anchored cinchonine nanocomposite as a heterogeneous catalyst in aqueous media. Without the need for an additional surfactant, rice husk was utilized as a raw material to create nanosilica. Through the grafting of 3-mercaptopropyl) trimethoxysilane, the rice husk nanosilica was modified. Next, azobisisobutylonitrile initiator was used to trigger the thiol-ene free radical interaction of the SH groups with the Cinchonine's alkene function. The morphology and structure of the nano SiO2-S-cinchonine were characterized using fourier transform infrared spectra, field emission scanning electron microscope, and energy-dispersive X-ray spectroscopy. The catalytic activity of the nanocomposite was investigated in the synthesis of 2-arylideneindan-1,3-diones and 2-arylidene-5,5-dimethyl-1,3-cyclohexanedione through an aqueous medium at 80 °C by the Knoevenagel condensation reaction. The advantages of this method are simple methodology, high yields, easy work-up, and green solvent.

One-pot multicomponent photo-induced eosin-Y catalyzed synthesis of 2-amino oxa/thiazine derivatives

An effective and advantageous one-pot multicomponent photo-induced methodology has been developed for the synthesis of biologically potent 2-amino-4H-1,3-oxa/thiazine from substituted benzaldehyde, ethynylbenzene and urea/thiourea catalyzed by eosin-Y at room temperature using EtOH as a green solvent with wide range of applications in pharmaceutical and agriculture industries. This proposed work emphasizes to investigate an accessible, safe, easy and convenient method for the synthesis of 2-amino oxa/thiazine derivatives with good to excellent yield.

Recommended Practices for the Electrochemical Recovery of Cobalt from Lithium Cobalt Oxide: A Case Study of the Choline Chloride:Ethylene Glycol Deep Eutectic Solvent.

We recommend best practices for the recovery of cobalt from LiCoO2 (LCO) lithium-ion battery (LIB) cathodes by (i) leaching using green deep eutectic solvents (DES) and (ii) subsequent electrodeposition, through a case study of the choline chloride (ChCl):ethylene glycol (EG) DES. DES physical properties (conductivity, viscosity, and surface tension) were tailored by varying the composition between mole ratios of 1 : 2 and 1 : 5 (ChCl:EG). Examined along with leaching process parameters (temperature, duration), increasing the fraction of hydrogen bond donors (HBDs) decreased DES surface tension and enhanced leaching. Complete Co recovery was achieved using 1 : 5 ChCl:EG DES at 160 °C and 48 h. Leaching temperatures >160 °C are discouraged due to DES thermal degradation. The electrodeposition process was optimized for selective Co recovery with high faradaic efficiency. The leaching ability of the DES was antithetical to the stability of electrodeposition cell components and required operational parameter adjustment to minimize degradation. The optimized system (copper cathode and stainless-steel anode) employing 1 : 5 DES leachate exhibited a faradaic efficiency of ~80 %, specific Co recovery of ~0.8 mg hr<M-1 cm-1 at 50 °C and evidence of uniform deposition. DES surface tension is a key descriptor of metal recovery, and guidelines are presented to maximize selective Co recovery.

Technology Focus: EOR Operations (November 2024)

International agreements and national policies on environmental sustainability are changing the outlook for enhanced oil recovery (EOR) globally. These changes are highlighted by both monetary and intellectual commitments by oil companies around the world. Saudi Aramco has pledged $1.5 billion toward sustainable technology. In practice, members of Aramco’s EXPEC Advanced Research Center have collaborated with King Fahd University of Petroleum and Minerals to develop sustainable surfactants for use in high-temperature, high-pressure, and high-salinity carbonate reservoirs. They used no or only green solvents to produce soluble, stable surfactants with the potential for biodegradability. In Colombia, Ecopetrol is committed to reducing CO2 emission by 25% by 2030. As part of its efforts, it has been optimizing polymer injection in Chichimene, a heavy-oil field. By estimating life cycle greenhouse-gas emissions and energy consumption, it was able to show that polymer injection and its associated carbon intensity reduction could prevent the emission of 3,200 tons CO2 equivalent. To comply with the UK’s North Sea Transition Deal, which mandates a 50% reduction in offshore oil and gas emissions by 2030, Ithaca Energy and Energy Research Norway is using life-cycle assessment to guide more efficient heavy-oil recovery. By using low-dose polymer injection, instead of alternatives such as thermal EOR, it was able to increase exergy while also reducing CO2 emissions by 35%. In these studies, we already see the effect of the energy transition as companies turn away from traditionally effective but environmentally burdensome EOR methods such as steam injection and new polymers that show equal, if not greater, effectiveness with a reduced environmental cost. As we move forward with further regulation and innovation, it will be interesting to see how emerging technological developments in polymers, nanofluids, and even artificial intelligence can help producers meet both the economic and environmental criteria to maintain profitable fields. Recommended additional reading at OnePetro: www.onepetro.org. SPE 218653 Coinjection EOR Technology Increases Recovery and Reduces Greenhouse-Gas Emissions by G. Wasylchuk, GERI SPE 218690 Steam Generation Using Renewables Energy—An Integrated Approach for Enhanced Oil Recovery Applications by Mustafa Al Ajmi, Petroleum Development Oman, et al. SPE 218962 Reaching a Million Barrels in an Abu Dhabi Field by Focusing on Operations Efficiency by Masud J. Akhtar, Abu Dhabi National Oil Company, et al.

TEMPO as Hydrogen Atom Transfer Catalyst in Enhancing Iminyl Radical Cyclization of O-Acetyl Oxime toward Phenanthridines and Isoquinolines.

Herein, we present a strategy for promoting the cyclization of ortho-aryl or ortho alkenyl arylketone oxime ethers C-N bonds using TEMPO as a direct hydrogen atom transfer (HAT) catalyst. The reaction employs a green solvent and requires no introduction of metal additives. It only needs catalytic amount of TEMPO to drive the reaction. Gram-scale reaction yields the corresponding products with satisfactory yields, providing a novel and efficient method for the synthesis of phenanthridine and isoquinoline derivatives.

Correction to “Investigation of molecular interaction, performance of green solvent in esterification of ethanol and acetic acid at 298.15 K and at 1 atm”

Correction to “Investigation of molecular interaction, performance of green solvent in esterification of ethanol and acetic acid at 298.15 K and at 1 atm”

Green solvent-controlled switchable synthesis of six-membered N-heterocycles and seven-membered O-heterocycles

The BF3·OEt2 promoted switchable synthesis of six-membered N-heterocycles and seven-membered O-heterocycles from readily available feedstocks was developed by the adjustment of green solvents EA and EtOH. The polycyclic tetrahydropyrido[1,2-a]indole derivatives were constructed via hydride transfer-involved cut-sew strategy through sewing two different substituents on the vicinal C2 and C3 positions of indoles in EA by one-step. In addition, the dearomatization of the indole nucleus was achieved by the derivatization of the tetrahydropyrido[1,2-a]indoles to form the three-dimensional spiro polycycles. On the other hand, a variety of dihydrodibenzo[b,e]oxepines bearing triarylmethane moiety were provided in moderate to good yields in EtOH without needing to purify.

A Green Approach: Optimization of the UPLC Method Using DoE Software for Concurrent Quantification of Pioglitazone and Dapagliflozin in a SNEDDS Formulation for the Treatment of Diabetes.

Clinical trials revealed that pioglitazone (PGZ) and dapagliflozin (DGZ) not only maintain normal blood glucose levels but also reduce complications of diabetes mellitus. To meet the demand for simultaneous measurement of these drugs in fixed combinations, an optimized and green UPLC method is required. The present study utilized Design of Experiments (DoE) software to optimize analytical parameters for simultaneous drug analysis. The method was validated for its linearity, accuracy, and precision. Furthermore, the drug content was estimated in different pharmaceutical dosage forms. Finally, Analytical Greenness (AGREE) software was utilized to assess the environmental sustainability of the optimized UPLC method. Drugs were successfully separated using optimized conditions on the C18 Acquity BEH column (2.1 mm × 100 mm, 1.7 μm) at a temperature of 45 °C. The mobile phase consisted of ethanol and 9 mM ammonium formate buffer (43.7:56.3), with elution carried out at a flow rate of 0.246 mL/min. The optimized method showed excellent linearity (R 2 > 0.999), accuracy (92.45-109.25%), and good precision (RSD < 6.27%) for both drugs. In addition, the optimized UPLC method was able to determine the drug content within the marketed pharmaceutical dosage form accurately. The developed UPLC method also prioritized eco-friendliness by using green solvents to minimize the negative impact on the environment. The green UPLC method provides a reliable and accurate approach to estimate PGZ and DGZ in a fixed diabetes treatment combination. It promotes sustainable lab practices and paves the way for analytical methods for new dose combinations.