Absorption Of Organic Solvents Research Articles

Density-Tunable Aramid Nanofiber Foams for Flame Retardancy, Joule Heating, and Organic Solvent Absorption

Density-Tunable Aramid Nanofiber Foams for Flame Retardancy, Joule Heating, and Organic Solvent Absorption

Advanced superhydrophobic polylactic acid fibers with high porosity and biodegradability for efficient solvent recovery

The conventional oil-absorbing materials utilized for addressing oil and organic solvent pollution are plagued by the issue of secondary pollution. In this study, biodegradable porous polylactic acid (PLA) fiber materials were prepared using centrifugal spinning technology, with PLA and polyvinyl butyral (PVB) as raw materials. PVB was utilized as a pore-forming agent to fabricate multi-layered porous PLA fiber materials. When the content of PVB in the spinning solution was 14 %, the porous PLA fibers exhibited the maximum specific surface area of 60.7 m2/g and a porosity of up to 85.4 %, interior of the fiber contained numerous mesopores. Additionally, the porous PLA fibers demonstrated excellent superhydrophobic oil absorption properties, with a water static contact angle of 137.8° and oil or organic solvent absorption capacities ranging from 10 to 17.7 g/g. Furthermore, porous PLA fiber materials exhibited outstanding biodegradability, with a degradation mass loss rate of 42.3–45.1 %. Therefore, superhydrophobic and oleophilic biomass-based PLA fiber materials prepared in centrifugal spinning show promising applications in the recovery of organic solvents and oily substances.

Graphene Incorporated Sugar Derived Carbon Aerogel for Pyridine Adsorption and Oil-Water Separation.

Herein, we have synthesized a three-dimensional and hydrophobic graphene incorporated carbon aerogel (G-SCA) derived from sugar. G-SCA is being used as a multifunctional sorbent material for removing various advanced water-soluble and insoluble pollutants. Initially, G-SCA is being explored for the adsorption of nitroarenes (nitrophenols, 3-nitroaniline), an insecticide (Phoskill), an antibiotic (ciprofloxacin), and a pharmaceutical drug precursor (pyridine). Later, the same G-SCA is also explored in the absorption of various protic and aprotic organic solvents, and oils (including crude oil, waste cooking oil, and waste engine oil), with excellent recyclability checked up to 10 cycles. Moreover, oil-water separation experiments are also being done in various industrial wastewater and seawater samples to support the real-life accessibility of the present approach. Large-scale applicability of G-SCA is also checked by performing crude oil-seawater separation experiments using a laboratory-scale prototype demonstrating the successful continuous recovery of crude oil.

Raman Microscopic Investigation of Organic Solvent Concentration Profiles in Proton Exchange Membranes and Their Permeability

Direct alcohol fuel cells (DAFCs) suffer from severe problems related to the employed polymer electrolyte membranes, such as fuel crossover, resulting in low faradaic efficiency and performance of the fuel cell.1,2,3 We introduce a 3D-printed diffusion cell setup, which is capable of determining the interaction of membranes and organic solvents via confocal Raman microscopy.4 Thus, the suitability of proton exchange membranes (PEMs) for usage in DAFCs can be evaluated. In this setup, the membrane is clamped between two flow channels, similar to the flow field plates of a fuel cell. The donor channel is filled with an organic solvent-water mixture, and the receptor channel is filled with water. Depth scans through the membrane and the two flow channels provide concentration profiles of the organic solvent within the membrane, which are used to calculate membrane properties such as permeability and sorption coefficient (see Fig. 1).In this study, the membrane-solvent interactions between standard unreinforced and composite PEMs and various organic solvent solutions, such as 2-propanol, acetone, and ethanol, are investigated. All membranes analyzed show a preference for organic solvent absorption from 1 M solutions, with sorption coefficients ranging from 2.5 to 3.0. In addition to the absorption, the organic solvents permeate through the membrane. The corresponding permeabilities range from 10-5 to 10-4 cm² s-1. However, the permeabilities of the membranes for different solvents do not scale with their sorption coefficients, in contrast to the membrane swelling.This diffusion cell setup is an accessible and fast pre-screening method, which can enhance the development and evaluation of new ion exchange membranes for use in DAFCs and related applications.

Azolla Pinnata: Sustainable Floating Oil Cleaner of Water Bodies.

Various plant-based materials effectively absorb oil contaminants at the water/air interface. These materials showcase unparalleled efficiency in purging oil contaminants, encompassing rivers, lakes, and boundless oceans, positioning them as integral components of environmental restoration endeavors. In addition, they are biodegradable, readily available, and eco-friendly, thus making them a preferable choice over traditional oil cleaning materials. This study explores the phenomenal properties of the floating Azolla fern (Azolla pinnata), focusing on its unique hierarchical leaf surface design at both the microscale and nanoscale levels. These intricate structures endow the fern with exceptional characteristics, including superhydrophobicity, high water adhesion, and remarkable oil or organic solvent absorption capabilities. Azolla's leaf surface exhibits a rare combination of dual wettability, where hydrophilic spots on a superhydrophobic base enable the pinning of water droplets, even when positioned upside-down. This extraordinary property, known as the parahydrophobic state, is rare in floating plants, akin to the renowned Salvinia molesta, setting Azolla apart as a natural wonder. Submerged in water, Azolla leaves excel at absorbing light oils at the air-water interface, demonstrating a notable ability to extract high-density organic solvents. Moreover, Azolla's rapid growth, doubling in the area every 4-5 days, especially in flowing waters, positions it as a sustainable alternative to traditional synthetic oil-cleaning materials with long-term environmental repercussions. This scientific lead could pave the way for more environmentally friendly approaches to mitigate the negative impacts of oil spills and promote a cleaner water ecosystem.

Ultralight and Robust Covalent Organic Framework Fiber Aerogels.

Shaping covalent organic frameworks (COFs) into macroscopic objects with robust mechanical properties and hierarchically porous structure is of great significance for practical applications but remains formidable and challenging. Herein, a general and scalable protocol is reported to prepare ultralight and robust pure COF fiber aerogels (FAGs), based on the epitaxial growth synergistic assembly (EGSA) strategy. Specifically, intertwined COF nanofibers (100-200nm) are grown in situ on electrospinning polyacrylonitrile (PAN) microfibers (≈1.7µm) containing urea-based linkers, followed by PAN removal via solvent extraction to obtain the hollow COF microfibers. The resultant COF FAGs possess ultralow density (14.1-15.5mg cm-3) and hierarchical porosity that features both micro-, meso-, and macropores. Significantly, the unique interconnected structure composed of nanofibers and hollow microfibers endows the COF FAGs with unprecedented mechanical properties, which can fully recover at 50% strain and be compressed for 20 cycles with less than 5% stress degradation. Moreover, the aerogels exhibit excellent capacity for organic solvent absorption (e.g., chloroform uptake of >90g g-1). This study opens new avenues for the design and fabrication of macroscopic COFs with excellent properties.

Intrinsic low‐dielectric‐constant polyimides based on a novel diamine having −CF3 groups and kinkable 1,4‐diisopropylbenzene units

AbstractPolyimides (PIs) with low dielectric constants and optical transparency are of great interest in 5G/6G communication applications and in the microelectronics industry, where they are used as interlayer dielectric materials, wearable display devices and so forth. In this study, we designed and synthesized a novel fluorinated diamine called 4,4′‐(1,4‐phenylenebis(propane‐2,2‐diyl))diphenoxybis(2‐(trifluoromethyl)‐4‐aminobenzene) (BPBTAB) monomer from bisphenol‐P having diisopropyl benzene units and fabricated four novel BPBTAB‐X PIs. These PI films possess excellent properties such as a low dielectric constant (1.13–1.84 at 1 MHz), high 5% loss temperature (395–491 °C), moderate glass transition temperature (223–254 °C), good tensile modulus (0.827–1.076 GPa), excellent optical properties (T450 up to 83.37%), low moisture absorption (<0.63%) and good solubility in organic solvents. Hence, the as‐synthesized PI films exhibit excellent comprehensive properties for high‐frequency 5G/6G communication applications. © 2023 Society of Chemical Industry.

Condensable Gases Capture with Ionic Liquids.

Condensable gases are the sum of condensable and volatile steam or organic compounds, including water vapor, which are discharged into the atmosphere in gaseous form at atmospheric pressure and room temperature. Condensable toxic and harmful gases emitted from petrochemical, chemical, packaging and printing, industrial coatings, and mineral mining activities seriously pollute the atmospheric environment and endanger human health. Meanwhile, these gases are necessary chemical raw materials; therefore, developing green and efficient capture technology is significant for efficiently utilizing condensed gas resources. To overcome the problems of pollution and corrosion existing in traditional organic solvent and alkali absorption methods, ionic liquids (ILs), known as "liquid molecular sieves", have received unprecedented attention thanks to their excellent separation and regeneration performance and have gradually become green solvents used by scholars to replace traditional absorbents. This work reviews the research progress of ILs in separating condensate gas. As the basis of chemical engineering, this review first provides a detailed discussion of the origin of predictive molecular thermodynamics and its broad application in theory and industry. Afterward, this review focuses on the latest research results of ILs in the capture of several important typical condensable gases, including water vapor, aromatic VOCs (i.e., BTEX), chlorinated VOC, fluorinated refrigerant gas, low-carbon alcohols, ketones, ethers, ester vapors, etc. Using pure IL, mixed ILs, and IL + organic solvent mixtures as absorbents also briefly expanded the related reports of porous materials loaded with an IL as adsorbents. Finally, future development and research directions in this exciting field are remarked.

Synthesis and Properties of New 3-Heterylamino-Substituted 9-Nitrobenzanthrone Derivatives

In the present study, new fluorophores based on disubstituted benzanthrone derivatives were designed starting from 9-nitro-3-bromobenzanthrone with nucleophilic substitution of the bromine atom with some secondary cyclic amines. It has been found that this reaction is positively affected by the presence of a nitro group in comparison with 3-bromobenzanthrone. The new compounds exhibit intense absorption and pronounced luminescent properties in various organic solvents. In this regard, their photophysical properties were evaluated with an experimental study of the solvatochromic behavior of the obtained compounds in various solvents. It has recently been found that the addition of an electron-withdrawing nitro group to the benzanthrone core increases its first- and second-order hyperpolarizability. Such dyes can be used in the fabrication of optical limiter devices. Therefore, the developed fluorescent molecules have a potential prospect for extensive application in optoelectronics.

Sustainable and Elastic Carbon Aerogel by Polydimethylsiloxane Coating for Organic Solvent Absorption and Potential Application for Sensors (Infections, Environmental, Wearable Sensors, etc.)

Carbon aerogel is a promising material in various applications, such as water treatment, insulators, catalysts, and sensors, due to its porosity, low density, conductivity, and good chemical stability. In this study, an inexpensive carbon aerogel was prepared through lyophilization and post-pyrolysis using waste paper. However, carbon aerogel, in the form of short belts, is randomly entangled without a crosslinking agent and has weak mechanical properties, thus limiting its applications, which would otherwise be various. In this paper, a novel strategy is proposed to fabricate a PDMS-coated carbon aerogel (Aerogel@PDMS). Benefiting from microwave heating, precise PDMS coating onto the carbon frame was able to be carried out in a short amount of time. PDMS coating firmly tied the carbon microstructure, maintaining a unique aerogel property without blocking its porous structure. FE-SEM, RAMAN, XPS, and FT-IR were all used to confirm the surface change in PDMS coating. Compressible stability and water contact angle measurement showed that Aerogel@PDMS is a perspective organic solvent absorbent due to its good resilience and its hydrophobicity, and, as a result, its organic solvent absorption capacity and repeated absorption were evaluated, ultimately suggesting a promising material in oil clean-up and pollution remediation in water. Based on our experimental results, we identified elastic carbon aerogels provided by a novel coating technology. In the future, then, the developed carbon/PDMS composite can be examined as a promising option for various applications, such as environmental sensors, virus sensors, and wearable sensors.

Multifunctional lightweight PANI/Ti3C2Tx‐PVDF composite foam for efficient microwave absorption

AbstractThe development of multifunctional and efficient microwave‐absorbing materials for various environments is essential to safeguard human health and combat interference in the operation of precision electronic apparatus. Specifically, Ti3C2Tx is attractive for microwave absorption (MA) due to its ultra‐low thickness, high conductivity, and high polarizability. However, the MA performance of Ti3C2Tx is limited by its mismatched impedance. To meet the high requirement in MA performance, a lightweight PANI/Ti3C2Tx‐PVDF composite foam was fabricated by a NaCl‐template method and dipping absorption in this study. The MA performance of the PANI/Ti3C2Tx‐PVDF composite foam can be regulated by both the composition and the loading content of PANI/Ti3C2Tx in composite foam. After loading with 25 wt.% PANI/Ti3C2Tx, the 2.33 mm‐thick PANI/Ti3C2Tx‐PVDF composite foam reached the optimal minimum reflection loss (RLmin) of −65.21 dB at 9.23 GHz and effective bandwidth of 2.61 GHz in the range of 8.20–10.81 GHz. The favorable MA performance of the composite foam was mainly ascribed to the great impedance matching and strong dielectric loss, which originated from the modulated conductivity and porous structure. Moreover, the PANI/Ti3C2Tx‐PVDF composite foam integrated MA performance, thermal insulation function, and organic solvent absorption capacity to show multifunctionality for various applications. In summary, this study may pave the way for the facile fabrication of next‐generation multifunctional high‐efficient MA materials.

Assessment of various forms of cellulose-based Luffa cylindrica (mat, flakes and powder) reinforced polydimethylsiloxane composites for oil sorption and organic solvents absorption

Oil spillage has damaged public health noticeably and contributed to significant environmental deterioration. As a result, a significant amount of effort has been spent on investigating and developing the sorbent materials capable of separating oil from water. Thus, the sorbent materials that could be effective particularly in oil spill disposal and resolve such environmental issue remain to be explored. We have proposed luffa cylindrica (LC)-polydimethylsiloxane (PDMS) composite forms to remove the oil and organic components that might be hazardous to aquatic organisms. The scaffolds were fabricated using hand lay-up method with various forms of luffa cylindrica i.e., LC mat, flakes and powder. Various characterizations such as scanning electron microscopy (SEM), atomic force microscopy (AFM), thermogravimetric analysis (TGA), effective porosity, surface wettability, mechanical stability, cytotoxicity and sorption behavior with respect to oil, phosphate buffer saline (PBS) and few organic solvents were performed. The results showed that the scaffold in combination with P-L flakes was highly effective in eradicating oil spills and removing harmful components of crude oil. Scaffolds composed of P-L mat, P-L flakes, P-L powder, and PDMS (P) exhibited oil absorption efficacy around 16.09 ± 4.62 %, 24.49 ± 3.55 %, 15.52 ± 2.67 % and 5.52 ± 1.44 %, respectively. We anticipate that the proposed scaffolds have the tremendous potential to provide a solution to this significant environmental remediation issue and to serve as a cost-effective method for removing oil spills and hazardous crude oil components.

Encapsulating covalent organic frameworks (COFs) in cellulose aerogels for efficient iodine uptake

Efficient capture and storage of radioiodine are of great importance for developing nuclear energy and tackling nuclear waste, which however remain challenging due to the scarcity of powerful materials. In this work, we rationally design and fabricate a hybrid material by encapsulating covalent organic frameworks (COFs) into ultralight cellulose aerogels for efficient iodine (I2) capture. Two kinds of functionalized cellulose precursors that can be covalently cross-linked are synthesized. Solvothermally synthesized COF particles with a uniform diameter of ∼ 500 nm are then introduced into the precursors followed by freeze drying to produce hybrid aerogels. With the presence of rich and ordered micropores afforded by COFs, these highly porous aerogels exhibit excellent organic solvent absorption performances and high uptake capacities toward solvent-dissolved and vaporized I2. More importantly, in view of the processable and robust structure, we realize the shaping of hybrid aerogels into aerogel columns to effectively capture I2 vapor and I2 solute in continuous operations. Therefore, this work not only provides a new way to shape COF materials but also could inspire the design of viable platforms for high-performance I2 capture.

Dynamics of absorption and evaporation of organic solvents in electrically conductive wood

Dynamics of absorption and evaporation of organic solvents in electrically conductive wood

Methylated Chromenoquinoline as a Novel Nucleus Fluorescent Probe for Nucleic Acid Imaging.

Two chromenoquinoline-based fluorescent probes 1a-b have been synthesized and investigated. Photofading behaviors of compounds 1a-b showed that at least 89% absorption remained after 6h irradiating, meanwhile, many of ions and amino acids had negligible impacts on their fluorescence intensity, which meant they had excellent photostability and selectivity. Probes 1a-b exhibited strong absorption and emission in organic solvents with large fluorescence quantum yields, even in water probe 1a still had a relatively large fluorescence quantum yield (20%). Combined with DFT calculation, the influence of alkylation on optical properties of 1b was elucidated. In addition, the fluorescence intensity of probe 1b with red emission enhanced by 5.4-fold and 5.3-fold after DNA and RNA added, and the fluorescence quantum yield increased from 3% to 17% and 14%, respectively, but the neutral molecule 1a had no response to nucleic acid. Furthermore, confocal microscopy imaging of probes 1a-b showed that 1a targeted lipid droplets while the methylated probe 1b to nucleus in living HeLa cells. The results indicated that the subcellular targeting zone could be changed by alkylation of nitrogen atom on chromenoquinoline-based conveniently, which provided a new idea for designing and synthesizing new subcellular labeled probes.

Facile fabrication of hierarchically porous melamine foam@COF composite for sample treatment of non-targeted food safety analysis and oil/water separation

The design of high-efficiency adsorbents for facile and rapid sample treatment of non-targeted food safety analysis and oil/water separation is challenging but of great significance to food and environment safety. To overcome the poor processability of covalent organic frameworks (COFs) powders and improve their application performances, a heteropore COF-based monolithic material (MF@COF composite) was prepared by selecting melamine foam (MF) as a supporter, whose surface has abundant amino groups, which makes the direct in-situ growth of COF and thus the one-pot synthesis of MF@COF possible. As-prepared MF@COF integrates the advantages of MF and COF, giving attractive properties such as highly hierarchical pores, strong hydrophobicity, ultralight weight, robust stability, good mechanical elasticity, and processability. These, together with the easy operation feature of monolithic material, make MF@COF work well for the sample treatment of non-targeted food safety analysis and oil/water separation. Nearly complete matrices removal from 6 kinds of representative fat-rich foods was achieved in 30 s, accompanied by the “full recovery” of 323 chemical hazards. The good oil/water separation capability was demonstrated by selective removal of light oil and heavy oil from oil/water systems, demulsification of oil/water emulsion, as well as 35–140 times weight increase after organic solvent or oil absorption.

Boronic acid derived salicylidenehydrazinopyridine (BOSPY) complexes with aggregation-induced emission for fluorescence imaging of cellular organelles

A series of boronic acid derived salicylidenehydrazinopyridine complexes have been synthesized from the condensation of 2-hydrazinopyridine or 2-hydrazinoquinoline and salicylaldehyde then followed by complexation with various boronic acids. Their X-ray structures demonstrate that the boron atoms adopt a tetrahedral geometry and the aryl substituents from arylboric acids along the vertical axis gave the molecule stereotactic structure and induced molecular chirality. These dyes have good solubility on organic solvents due to the nonplanar curved structure and the presence of axial-substituted groups that provide steric protection. They have strong visible-light absorption, weak emission and large Stoke shifts in organic solvents. Interestingly, molecular aggregates of these new boron complexes experienced the transformation from H-type aggregation to J-type aggregation and exhibited strong aggregation-induced emission (AIE) activities. These novel AIE dyes showed great potential as bioimaging dyes, and two complexes were mainly distributed in lipid droplets of cells in colocalization experiments.

High removal of chlorinated solvents by reusable polydimethylsiloxane based absorbents

AbstractThe objective of this work is to prepare absorbent materials based on polydimethylsiloxane (PDMS) for the absorption of organic solvents by a relative simple method, with large absorption capacities and reusability. Different particles (ZnO, MgSO4, ZnCl2, and NaHCO3) were first incorporated in PDMS and then removed by immersion in HCl (c) or water. The absorbent materials were characterized by TGA, mercury porosimetry, stress–strain curves, SEM, EDS, XPS, FTIR, and water contact angle. The materials can absorb polar organic chlorinated solvents (carbon tetrachloride, dichloroethene, dichloromethane, and chloroform) more than four times its own weight. Other solvents were also tested showing 2–3 times its own weight. Additionally, these materials show demulsification properties and absorption of oleophilic compounds. The reusability of the material makes them good candidates for remediation of polluted water.

Total site modeling and optimization for petrochemical low-carbon retrofits using multiple CO2 emission reduction methods

Aiming at the carbon dioxide (CO2) emissions from energy and material flow streams in petrochemical sites, a bi-objective optimization strategy based on retrofit improvements and total site techniques is constructed, which is referred to as the petrochemical CO2 emission reduction comprehensive (Petro-CERC) model. The fossil fuels for heat, steam and power provision, as well as the fossil-fired power importation are condsidered to shift to biomass fuel and renewable power in utilities and process units. A waste heat up-graded utilization system is introduced and adopted to improve the efficiency of heat energy, and a green combined heat and power system based on renewable and sustainable resources is established to reconstruct the conventional utility system. Carbon capture by the organic amine solvent absorption process is also integrated into the bi-objective optimization strategy. The CO2 emission reduction methods were applied individually to a petrochemical site in South China with an annual emission of 3.2 million tons CO2 for the sensitivity analysis. The proposed Petro-CERC model was then performed for the optimization of the combined application of the CO2 emission reduction methods. From the perspective of both carbon neutrality and economy, the optimal value at the trade-off point of CO2 emission is 464 thousand tons CO2/year, and the cost of achieving an 85% reduction of CO2 emission is $44.9 million. Further, the CO2 emission reduction strategies in different petrochemical sites are coupled with four different regions on a national scale according to the matching degree of the three standards of technical feasibility, economic development status and geographical appearance. Consequently, a multi-scenario application based on the four regions is applied in this case, and the feasibility of the CO2 emission reduction methods to achieve the near carbon neutral goal in these scenarios is evaluated.

Cellulose Source Tailors the Physical and Structural Properties of Double-Functionalized Aerogels

ABSTRACT Cellulose aerogels are solid materials with high porosity, low density, and large surface area, and show excellent absorption of mechanical stress. These characteristics are appropriate for the development of new high-value products. However, over the years, it has been increasingly difficult to compare different studies about this material due to the different approaches used. In the present work, three different raw materials, bacterial cellulose from synthetic medium (BC), bacterial cellulose from cashew juice permeate (BCP), and eucalyptus nanocellulose (EC) were double-functionalized with TEMPO oxidation followed by silanization and freeze-dried, resulting in three different types of cellulose aerogels. These aerogels were evaluated for their performance in the absorption of organic oils/solvents and mechanical properties. The raw materials lead to aerogels with different characteristics. BC aerogel has the best mechanical properties and absorption capacity after 7 cycles; BCP aerogel presented the highest values for oil absorption and EC aerogel for organic solvent absorption.