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Hydrophobic polymerized ionic liquids for trace metal solid phase extraction: thallium transfer from hydrochloric acid media
It is known that some neat room-temperature hydrophobic ionic liquids can extract metallic species from aqueous solutions. The unique properties of such organic media allow for the application of polymerization techniques to convert the liquid organic phase to a solid one. In this work, a pyrrolidinium-based ionic liquid and a corresponding polymer with bis(trifluoromethanesulfonyl)imide counter anion have been considered for optimization of thallium(III) migration in liquid-liquid and solid-liquid extraction systems. Neither trivalent indium nor monovalent thallium were absorbed by the polymer layer. A mathematical model to describe the mechanism of metal extraction in these systems has been developed. Thermodynamic parameters as adsorption enthalpy, entropy, and Gibbs energy have also been determined.
Liquid-Liquid Extraction of Iron in Hydrochloric Acid with Quaternary Amines in Microfluidic Devices.
No abstract provided.
Feasibility study of the application of existing techniques to remotely monitor hydrochloric acid in the atmosphere
A critical evaluation of existing optical remote sensors for HCl vapor detection in solid propellant rocket plumes is presented. The P branch of the fundamental vibration-rotation band was selected as the most promising spectral feature to sense. A computation of transmittance for HCl vapor, an estimation of interferent spectra, the application of these spectra to computer modelled remote sensors, and a trade-off study for instrument recommendation are also included.
An anomalous reaction of aceto-4-/or 6-/ nitro-2,5-xylidides with hydrochloric acid.
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Atmospheric scavenging of hydrochloric acid
The scavenging of hydrogen chloride from a solid rocket exhaust cloud was investigated. Water drops were caused to fall through a confined exhaust cloud and then analyzed to determine the amount of HCl captured during fall. Bubblers were used to measure HCl concentration within the chamber. The measured chamber HCl concentration, together with the measured HCl deposition on the chamber walls, accounted for 81 to 94% of the theoretical HCl. It was found that the amount of HCl captured was approximately one-half of that predicted by the Frossling correlation. No effect of humidity was detected through a range of 69-98% R.H.. The scavenging of HCl from a solid rocket exhaust cloud was calculated using an idealized Kennedy Space Center rain cycle. Results indicate that this cycle would reduce the cloud HCl concentration to 20.6% if its value in the absence of rain.
Quantification of hydrochloric acid and particulate deposition resulting from Space Shuttle launches at John F. Kennedy Space Center, Florida, U.S.A.
Results are presented from studies designed to identify deposition patterns and quantify the ecosystem loading rates of exhaust constituents (which are primarily Al2O3 and HCl) from the Space Shuttle solid rocket motors in the area of the Kennedy Space Center launch pad. Results of measurements indicate that, under certain meteorological conditions, as much as 7.1 x 10 exp 3 kg of particulates and 3.4 x 10 exp 3 kg HCL can be deposited to the near-field environment beyond the launch pad perimeter fence during one STS launch.
Intergranular Corrosion of High-purity Aluminum in Hydrochloric Acid I : Effects of Heat Treatment, Iron Content, and Acid Composition
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Intergranular corrosion of high-purity aluminum in hydrochloric acid II : grain-boundary segregation of impurity atoms
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Hydrochloric acid and the chlorine budget of the lower statosphere
Concentrations of HCl measurements in the lower stratosphere in 1993 by the ALIAS instrument on the ER-2 aircraft reveal that only 40% of inorganic chlorine (Cl(y), inferred from in situ measurements of organic chlorinated sources gases) is present as HCl, significantly lower than model predictions. Although the sum of measured HCl, ClO and ClONO2, the latter inferred from measurements of ClO and NO2 equals Cl(y) to within the incertainty of measurement, it is systematically less than Cl(y) by 30-50%. This discrepancy suggests that concentrations of ClONO2 may exceed those of HC; near 20 km altitude, consistent with a slower photolysis rate for ClONO2 than calculated using recommended cross sections. Comparison of profiles of HCl measured during 1992 and 1193 at mid-latitudes by balloon (BLISS and MARKIV), space shuttle (ATMOS), and satellite (HALOE) instruments with the aircraft data reveal an apparent pressure dependence to the HCl to Cl(y) ratio, consistent with a factor of 3-10 reduction in the photolysis rate for ClONO2 at ER-2 altitudes. However, the diurnal variation of ClO is well-simulated by models using the recommended photolysis rate, and simulations measurements of ClONO2 and HCl at mid-latitudes by ATMOS and MARKIV report HCl (HCL+ ClONO2) ratios greater than or equal to 50%. Premliminary measurements by ALIAS in the southern hemisphere report HCl/Cl(y) values of about 75%.
Hydrochloric Acid and the Chlorine Budget of the Lower Stratosphere
Concentrations of hc1 measured in the lower stratosphere in 1993 by the ALIAS instrument on the ER-2 aircraft reveal that only 40% of inorganic chlorine (CL sub y, inferred from in situ measurements of organic chlorinated source gases) is present as HC1, significantly lower than model predictions.
Coal fly ash interaction with environmental fluids: Geochemical and strontium isotope results from combined column and batch leaching experiments
The major element and Sr isotope systematics and geochemistry of coal fly ash and its interactions with environmental waters were investigated using laboratory flow-through column leaching experiments (sodium carbonate, acetic acid, nitric acid) and sequential batch leaching experiments (water, acetic acid, hydrochloric acid). Column leaching of Class F fly ash samples shows rapid release of most major elements early in the leaching procedure, suggesting an association of these elements with soluble and surface bound phases. Delayed release of certain elements (e.g., Al, Fe, Si) signals gradual dissolution of more resistant silicate or glass phases as leaching continues. Strontium isotope results from both column and batch leaching experiments show a marked increase in {sup 87}Sr/{sup 86}Sr ratio with continued leaching, yielding a total range of values from 0.7107 to 0.7138. For comparison, the isotopic composition of fluid output from a fly ash impoundment in West Virginia falls in a narrow range around 0.7124. The experimental data suggest the presence of a more resistant, highly radiogenic silicate phase that survives the combustion process and is leached after the more soluble minerals are removed. Strontium isotopic homogenization of minerals in coal does not always occur during the combustion process, despite the high temperatures encountered in the boiler. Early-released Sr tends to be isotopically uniform; thus the Sr isotopic composition of fly ash could be distinguishable from other sources and is a useful tool for quantifying the possible contribution of fly ash leaching to the total dissolved load in natural surface and ground waters.
Ambient cure polyimide foams
Flame and temperature resistant polyimide foams are prepared by the reaction of an aromatic dianhydride, (pyromellitic dianhydride) with an aromatic polyisocyanate, (polymethylene polyphenylisocyanate), in the presence of an inorganic acid and furfuryl alcohol. Usable acids include dilute sulfuric acid, dilute nitric acid, hydrochloric acid, polyphosphoric acid, and phosphoric acid, with the latter being preferred. The dianhydride and the isocyanate in about equimolar proportions constitute about 50% of the reaction mixture, the rest being made up with the acid and the alcohol in a ratio of about 1:10. An exothermic reaction between the acid and the alcohol provides the heat necessary for the other components to polymerize without recourse to external heat sources. The mixture can be sprayed on any surface to form polymeric foam in locations where the application of heat is not practical or possible, for instance, between walls or on mine tunnel surfaces.
Pretreatment Solution for Water Recovery Systems
Chemical pretreatments are used to produce usable water by treating a water source with a chemical pretreatment that contains a hexavalent chromium and an acid to generate a treated water source, wherein the concentration of sulfate compounds in the acid is negligible, and wherein the treated water source remains substantially free of precipitates after the addition of the chemical pretreatment. Other methods include reducing the pH in urine to be distilled for potable water extraction by pretreating the urine before distillation with a pretreatment solution comprising one or more acid sources selected from a group consisting of phosphoric acid, hydrochloric acid, and nitric acid, wherein the urine remains substantially precipitate free after the addition of the pretreatment solution. Another method described comprises a process for reducing precipitation in urine to be processed for water extraction by mixing the urine with a pretreatment solution comprising hexavalent chromium compound and phosphoric acid.
Wear of iron and nickel in corrosive liquid environments
Friction and wear behavior of Fe and Ni sliding on aluminum oxide in aerated sulfuric acid and hydrochloric acid were investigated. The results show that the concentration of acid is an important factor in controlling the metal loss caused by wear corrosion processes in the acids. At very dilute acid concentration (10 to the -4 N), Fe behaves differently from Ni. Fe develops a soft, friable deposit, while Ni develops no corrosion layer. The formation and removal of the corrosion deposit on Fe resulted in high metal loss and coefficient of friction, as compared to the relatively low metal loss and coefficient of friction observed for Ni. At slightly higher acid concentration (10 to the -3 and 10 to the -2 N), no corrosion products were produced on both Fe and Ni. Wear of Fe and Ni was generally at a minimum. At higher acid concentration (10 to the -1 N and above), loss of Fe and Ni increased as the acid concentration increased. In sulfuric acid the maximum loss of both Fe and Ni was at 7.5 N (30%) concentration, and the metal losses of both Fe and Ni dropped markedly at 15 N (50%) and above. In hydrochloric acid, however, the Fe loss continued to increase with the increase of acid concentration, and the maximum Fe loss occurred in the most concentrated acid (12.1 N, 37%). There were variations in loss with Ni from specimen to specimen examined in hydrochloric acids (10 to the -1 N and above). The coefficient of friction for Ni increased slightly with an increase in acid concentration up to 10 to the -2 N. When corrosion started to dominate in the wear-corrosion process, the coefficient of friction decreased in both sulfuric and hydrochloric acids at 10 to the -1 N and above.
Wear of iron and nickel in corrosive liquid environments
Friction and wear behavior of Fe and Ni sliding on aluminum oxide in aerated sulfuric acid and hydrochloric acid were investigated. The results show that the concentration of acid is an important factor in controlling the metal loss caused by wear corrosion processes in the acids. At very dilute acid concentration (10 to the -4 N), Fe behaves differently from Ni. Fe develops a soft, friable deposit, while Ni develops no corrosion layer. The formation and removal of the corrosion deposit on Fe resulted in high metal loss and coefficient of friction, as compared to the relatively low metal loss and coefficient of friction observed for Ni. At slightly higher acid concentration (10 to the -3 and 10 to the -2 N), no corrosion products were produced on both Fe and Ni. Wear of Fe and Ni was generally at a minimum. At higher acid concentration (10 to the -1 N and above), loss of Fe and Ni increased as the acid concentration increased. In sulfuric acid the maximum loss of both Fe and Ni was at 7.5 N (30 percent) concentration, and the metal losses of both Fe and Ni dropped markedly at 15 N (50 percent) and above. In hydrochloric acid, however, the Fe loss continued to increase with the increase of acid concentration, and the maximum Fe loss occurred in the most concentrated acid (12.1 N, 37 percent). There were variations in loss with Ni from specimen to specimen examined in hydrochloric acids (10 to the -1 N and above). The coefficient of friction for Ni increased slightly with an increase in acid concentration up to 10 to the -2 N. When corrosion started to dominate in the wear-corrosion process, the coefficient of friction decreased in both sulfuric and hydrochloric acids at 10 to the -1 N and above.
Materials Data on H18RuN5(ClO)2 by Materials Project
(RuN5H15O)2(H2O)2(HCl)2Cl2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four hydrochloric acid molecules, four hydrochloric acid molecules, four water molecules, and two RuN5H15O clusters. In each RuN5H15O cluster, Ru3+ is bonded to six N3- atoms to form edge-sharing RuN6 octahedra. There are a spread of Ru–N bond distances ranging from 2.03–2.17 Å. There are five inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted water-like geometry to two equivalent Ru3+ and two H1+ atoms. Both N–H bond lengths are 1.03 Å. In the second N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to one Ru3+ and three H1+ atoms. There is two shorter (1.03 Å) and one longer (1.09 Å) N–H bond length. In the third N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to one Ru3+ and three H1+ atoms. There is two shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the fourth N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to one Ru3+ and three H1+ atoms. All N–H bond lengths are 1.03 Å. In the fifth N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to one Ru3+ and three H1+ atoms. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. There are fifteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fifth H1+ site, H1+ is bonded in a distorted single-bond geometry to one N3- and one O2- atom. The H–O bond length is 1.65 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. O2- is bonded in a distorted single-bond geometry to two H1+ atoms.
Materials Data on CuH18C4N10(ClO)2 by Materials Project
(CuH14(C2N5)2)2(H2O)2(H2OCl)2Cl2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two hydrochloric acid molecules; two hydrochloric acid, monohydrate molecules; two water molecules; and two CuH14(C2N5)2 clusters. In each CuH14(C2N5)2 cluster, Cu2+ is bonded in a square co-planar geometry to four N3- atoms. There is one shorter (1.95 Å) and three longer (1.96 Å) Cu–N bond length. There are four inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to three N3- atoms. There are a spread of C–N bond distances ranging from 1.31–1.38 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to three N3- atoms. There are a spread of C–N bond distances ranging from 1.31–1.37 Å. In the third C4+ site, C4+ is bonded in a trigonal planar geometry to three N3- atoms. There are a spread of C–N bond distances ranging from 1.31–1.38 Å. In the fourth C4+ site, C4+ is bonded in a trigonal planar geometry to three N3- atoms. There are a spread of C–N bond distances ranging from 1.31–1.37 Å. There are ten inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted trigonal planar geometry to one Cu2+, one C4+, and one H1+ atom. The N–H bond length is 1.02 Å. In the second N3- site, N3- is bonded in a trigonal planar geometry to one C4+ and two H1+ atoms. There is one shorter (1.01 Å) and one longer (1.02 Å) N–H bond length. In the third N3- site, N3- is bonded in a trigonal planar geometry to two C4+ and one H1+ atom. The N–H bond length is 1.05 Å. In the fourth N3- site, N3- is bonded in a trigonal planar geometry to one C4+ and two H1+ atoms. There is one shorter (1.01 Å) and one longer (1.02 Å) N–H bond length. In the fifth N3- site, N3- is bonded in a distorted trigonal planar geometry to one Cu2+, one C4+, and one H1+ atom. The N–H bond length is 1.02 Å. In the sixth N3- site, N3- is bonded in a distorted trigonal planar geometry to one Cu2+, one C4+, and one H1+ atom. The N–H bond length is 1.03 Å. In the seventh N3- site, N3- is bonded in a trigonal planar geometry to one C4+ and two H1+ atoms. Both N–H bond lengths are 1.02 Å. In the eighth N3- site, N3- is bonded in a trigonal planar geometry to two C4+ and one H1+ atom. The N–H bond length is 1.04 Å. In the ninth N3- site, N3- is bonded in a distorted trigonal planar geometry to one C4+ and two H1+ atoms. Both N–H bond lengths are 1.02 Å. In the tenth N3- site, N3- is bonded in a distorted trigonal planar geometry to one Cu2+, one C4+, and one H1+ atom. The N–H bond length is 1.03 Å. There are fourteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.