Impact of ionic liquids in environment and humans: An overview

2010 ◽  
Vol 29 (12) ◽  
pp. 1038-1054 ◽  
Author(s):  
Raquel FM Frade ◽  
Carlos AM Afonso
Keyword(s):  
Ionic Liquids ◽  
Physical State ◽  
Alkyl Chain ◽  
Large Range ◽  
Chemical Properties ◽  
Alkyl Chain Length ◽  
Molecular Structures ◽  
New Materials ◽  
Toxicological Data ◽  
Potential Applications

Ionic liquids enclose a large number of molecular structures consisting of a cation and an anion. Their physical state and their chemical properties can be tuned by different combination of the ions and a large number of ionic liquids have already been reported. Toxicity of ionic liquids is a subject of great importance concerning their likely use as greener solvents and new materials for a broad number of potential applications. This review provides relevant toxicological data published so far about this topic and includes a large range of ionic liquids based on different cations (imidazolium, pyridinium, pyrrolidinium, quaternary ammonium, quaternary phosphonium and guanidinium) and anions (halogens-Br, Cl, bis (trifluoromethyl)sulfonylamide, tetrafluoroborate, hexafluorophosphate, dicyanamide, acesulfame and saccharin, amongst others). In general, toxicity of ionic liquids depends on both ions and the effect of the cation alkyl chain length is very pronounced although the type of anion also exerts impact on the overall toxicity.

scholarly journals Silver Nanoparticles Stabilized with Phosphorus-Containing Heterocyclic Surfactants: Synthesis, Physico-Chemical Properties, and Biological Activity Determination

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1883
Author(s):  
Martin Pisárčik ◽  
Miloš Lukáč ◽  
Josef Jampílek ◽  
František Bilka ◽  
Andrea Bilková ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Biological Activity ◽  
Zeta Potential ◽  
Chain Length ◽  
Alkyl Chain ◽  
Chemical Properties ◽  
Alkyl Chain Length ◽  
Microbial Pathogens ◽  
Physico Chemical ◽  
Phosphorus Containing

Phosphorus-containing heterocyclic cationic surfactants alkyldimethylphenylphospholium bromides with the alkyl chain length 14 to 18 carbon atoms were used for the stabilization of silver nanodispersions. Zeta potential of silver nanodispersions ranges from +35 to +70 mV, which indicates the formation of stable silver nanoparticles (AgNPs). Long-chain heptadecyl and octadecyl homologs of the surfactants series provided the most intensive stabilizing effect to AgNPs, resulting in high positive zeta potential values and smaller diameter of AgNPs in the range 50–60 nm. A comparison with non-heterocyclic alkyltrimethylphosphonium surfactants of the same alkyl chain length showed better stability and more positive zeta potential values for silver nanodispersions stabilized with heterocyclic phospholium surfactants. Investigations of biological activity of phospholium-capped AgNPs are represented by the studies of antimicrobial activity and cytotoxicity. While cytotoxicity results revealed an increased level of HepG2 cell growth inhibition as compared with the cytotoxicity level of silver-free surfactant solutions, no enhanced antimicrobial action of phospholium-capped AgNPs against microbial pathogens was observed. The comparison of cytotoxicity of AgNPs stabilized with various non-heterocyclic ammonium and phosphonium surfactants shows that AgNPs capped with heterocyclic alkyldimethylphenylphospholium and non-heterocyclic triphenyl-substituted phosphonium surfactants have the highest cytotoxicity among silver nanodispersions stabilized by the series of ammonium and phosphonium surfactants.

Spectroscopic Study on Imidazolium-Based Ionic Liquids: Effect of Alkyl Chain Length and Anion

2012 ◽  
Vol 116 (11) ◽  
pp. 3512-3518 ◽  
Author(s):  
Enrico Binetti ◽  
Annamaria Panniello ◽  
Leonardo Triggiani ◽  
Raffaele Tommasi ◽  
Angela Agostiano ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Spectroscopic Study ◽  
Chain Length ◽  
Alkyl Chain ◽  
Alkyl Chain Length

Long alkyl chain quaternary ammonium-based ionic liquids and potential applications

2006 ◽  
Vol 8 (9) ◽  
pp. 798 ◽  
Author(s):  
Juliusz Pernak ◽  
Marcin Smiglak ◽  
Scott T. Griffin ◽  
Whitney L. Hough ◽  
Timothy B. Wilson ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Quaternary Ammonium ◽  
Alkyl Chain ◽  
Potential Applications ◽  
Long Alkyl Chain

Thermo-physical and tribological characteristics of ionic liquid-based rice bran oil as green cutting fluid

2021 ◽  
pp. 135065012110461
Author(s):  
Aswani K Singh ◽  
Varun Sharma
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Coefficient Of Friction ◽  
Rice Bran ◽  
Alkyl Chain ◽  
Rice Bran Oil ◽  
Alkyl Chain Length ◽  
Cutting Fluid ◽  
Cutting Fluids ◽  
Base Oil

During machining, the cutting fluids play an essential role in cooling and lubrication. In order to reduce the friction forces, the excessive amount of the cutting fluids are generally used. This, in turn, leads to wastage of the cutting fluids which results in a serious impact on the environment, health and cost of production. Therefore, the judicious use of lubricants is the foremost concern in the manufacturing industry. In order to mitigate these drawbacks, various alternatives have been developed in the last decade. In the present paper, ionic liquids have been proved as favourable sustainable alternative additives in the base oil. The effect of alkyl chain length of ionic liquids with base oil on the thermo-physical and tribological characteristics of cutting fluids including viscosity, wettability, anticorrosion behaviour, thermal stability, and coefficient of friction have been analysed. In the present study, pyrrolidinium and hexafluoro-phosphate (PF6) have been used as cation and anion, respectively, with rice bran oil as base oil. The five different ionic liquids have been dispersed in base oil by 1.0 wt%. It has been found that longer alkyl chain length showed the favourable results as compared to the shorter one. Results indicated that ionic liquid based cutting fluid attained ample enhanced thermophysical and tribological properties as compared to the neat rice bran oil. There has been 5.08% and 4.29% improvement in viscosity and thermal conductivity for IL4 + RBO in comparison to neat RBO. In addition, the wettability, coefficient of friction, and wear volume have been reduced by 20.34%, 53.79% and 57.87% correspondingly.

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