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Results for “liquid solution”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Synthesis and electroplating of high resolution insulated carbon nanotube scanning probes for imaging in liquid solutions

High resolution and isolated scanning probe microscopy (SPM) is in demand for continued development of energy storage and conversion systems involving chemical reactions at the nanoscale as well as an improved understanding of biological systems. We can use carbon nanotubes (CNTs) have large aspect ratios and, if leveraged properly, to develop high resolution SPM probes. Isolation of SPM probes can be achieved by depositing a dielectric film and selectively etching at the apex of the probe. Here, the fabrication of a high resolution and isolated SPM tip is demonstrated using electron beam induced etching of a dielectric film deposited onto an SPM tip with an attached CNT at the apex.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Surface-functionalized polyolefin fibers and their use in methods for extracting metal ions from liquid solutions

A fiber useful in the absorption of metal ions from aqueous solutions, the fiber comprising a polyolefin backbone having a diameter of at least 1 micron and having covalently appended on its surface halogen atoms and vinyl-addition polymeric grafts functionalized with metal-binding groups, such as at least one functional group selected from carboxylate, keto, aldo, amino, imino, nitrile, amido, oxime, amidoxime, imide dioxime, and hydroxamate groups. The vinyl-addition polymeric grafts may also be further functionalized with hydrophilic groups different from the metal-binding groups, wherein the hydrophilic groups may be selected from carboxylate, sulfone, sulfonate, phosphonate, alkylammonium, iminium, amide, pyrrolidone, and polyalkyleneglycol groups. Also described are methods for producing the functionalized fibers, and methods for using the functionalized fiber, particularly in extracting metal ions from metal-containing solutions.

Dai, Sheng↗
DOE OSTI2020

Amidoxime-functionalized materials and their use in extracting metal ions from liquid solutions

A method of producing a functionalized material that extracts metal ions from solution, the method comprising: (i) providing a precursor material having nitrile groups appended to its surface; and (ii) reacting said nitrile groups with hydroxylamine or a derivative thereof in the presence of a polar aprotic solvent at a temperature of 60-80° C. for at least 1 hour, to convert at least a portion of said nitrile groups to amidoxime and imide dioxime groups, followed by reaction with a base capable of hydrolyzing any remaining nitrile groups to carboxylic acid groups; wherein said functionalized material has a higher uranium absorption capacity than a functionalized material produced under same conditions except that the nitrile groups are reacted with hydroxylamine in only a protic solvent. The invention is also directed to functionalized materials produced by the above-described method, and methods for using the functionalized material for extracting metal ions from metal-containing solutions.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Amidoxime-functionalized materials and their use in extracting metal ions from liquid solutions

A method of producing a functionalized material that extracts metal ions from solution, the method comprising: (i) providing a precursor material having nitrile groups appended to its surface; and (ii) reacting said nitrile groups with hydroxylamine or a derivative thereof in the presence of a polar aprotic solvent at a temperature of 60-80° C. for at least 1 hour, to convert at least a portion of said nitrile groups to amidoxime and imide dioxime groups, followed by reaction with a base capable of hydrolyzing any remaining nitrile groups to carboxylic acid groups; wherein said functionalized material has a higher uranium absorption capacity than a functionalized material produced under same conditions except that the nitrile groups are reacted with hydroxylamine in only a protic solvent. The invention is also directed to functionalized materials produced by the above-described method, and methods for using the functionalized material for extracting metal ions from metal-containing solutions.

Janke, Christopher J.↗
DOE OSTI2015

Ionic liquids, electrolyte solutions including the ionic liquids, and energy storage devices including the ionic liquids

An ionic liquid including a phosphazene compound that has a plurality of phosphorus-nitrogen units and at least one pendant group bonded to each phosphorus atom of the plurality of phosphorus-nitrogen units. One pendant group of the at least one pendant group comprises a positively charged pendant group. Additional embodiments of ionic liquids are disclosed, as are electrolyte solutions and energy storage devices including the embodiments of the ionic liquid.

25 ENERGY STORAGE↗
DOE OSTI2021

Conversion of sugars to ionic liquids

Disclosed herein are methods for preparing sugar compositions. The methods include: i) forming a mixture including polysaccharide biomass and an ionic liquid solution, wherein the ionic liquid solution contains water and an ionic liquid, and the ionic liquid contains a) a cation and b) a sugar acid anion or a ketoacid anion; ii) maintaining the mixture under conditions sufficient to dissolve at least a portion of the polysaccharide present in the polysaccharide biomass; iii) adding at least one glycoside hydrolase to the mixture; and iv) maintaining the mixture containing the glycoside hydrolase under conditions sufficient to hydrolyze at least a portion of the dissolved polysaccharide, thereby forming the sugar compositions. The sugar compositions contain at least one monosaccharide or oligosaccharide. New sugar-based ionic liquids are also described.

Gladden, John M.↗
DOE OSTI2021

Switchable ionic liquids for biomass pretreatment and enzymatic hydrolysis

In one aspect, the present invention provides a method for preparing a sugar composition. The method includes: forming a mixture including polysaccharide biomass and an ionic liquid solution, wherein the ionic liquid solution contains water and an ionic liquid, and wherein the ionic liquid contains a dicarboxylic acid anion and a cation. The pH of the mixture is greater than or equal to about 10, and the molar ratio of the dicarboxylic acid anion to the cation is at least about 1:2. The method further includes: maintaining the mixture under conditions sufficient to dissolve at least a portion of the polysaccharide present in the polysaccharide biomass; reducing the pH of the mixture containing the dissolved polysaccharide to at least about 7; adding at least one glycoside hydrolase to the mixture having the reduced pH.

Liszka, Michael↗
DOE OSTI2019

Continuous production of pure liquid fuel solutions via electrocatalytic CO 2 reduction using solid-electrolyte devices

Electrocatalytic CO 2 reduction is often carried out in a solution electrolyte such as KHCO 3 (aq), which allows for ion conduction between electrodes. Thus, liquid products that form are in a mixture with the dissolved salts, requiring energy-intensive downstream separation. In this work, we report continuous electrocatalytic conversion of CO 2 to pure liquid fuel solutions in cells that utilize solid electrolytes, where electrochemically generated cations (such as H+) and anions (such as HCOO–) are combined to form pure product solutions without mixing with other ions. Using a HCOOH-selective (Faradaic efficiencies>90%) and easily scaled Bi catalyst at the cathode, we demonstrate production of pure HCOOH solutions with concentrations up to 12M. We also show 100h continuous and stable generation of 0.1 M HCOOH with negligible degradation in selectivity and activity. Production of other electrolyte-free C 2+ liquid oxygenate solutions, including acetic acid, ethanol and n-propanol, are also demonstrated using a Cu catalyst. Lastly, we show that our CO 2 reduction cell with solid electrolytes can be modified to suit other, more complex practical applications.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Halide Ions Effects on Surface Excess of Long Chain Ionic Liquids Water Solutions

The interfacial structure and composition of water solutions with alkylimidazolium ionic liquids varying in their halide anions ([C12mim][X], X = Cl and I) were investigated by X-ray near-total-reflection fluorescence spectroscopy and X-ray reflectivity measurements. We demonstrate that X-ray fluorescence and reflectivity techniques provide a more direct measurement of surface adsorption. Furthermore, we show that for [C12mim][Cl] and [C12mim][I] solutions with mixed inorganic salts (NaI, NaCl), I– ions replace Cl– above the critical micelle concentration (CMC) of [C12mim][Cl] at much lower concentrations of NaI, whereas NaCl concentrations a hundred times higher than the CMC of [C12mim][I] only partially replace the I– at the interface. Our surface-sensitive X-ray diffraction and spectroscopy provide two independent tools to directly determine the surface adsorption of ionic surfactants and the interfacial composition of the surface films.

36 MATERIALS SCIENCE↗