The objective of this work was to develop nanomaterial inhibitor with long squeeze life for oil and gas production. Different surfactants, such as trisodium citrate (Na3Cit), cetyltrimethyl ammonium ...bromide, benzethonium chloride (Hyamine), and bipyridinium dibromide (Gemini), were added to synthesize nanoparticle Ca-DTPMP inhibitor at pH 9.0. The inhibitors were characterized by scanning electron microscope and dynamic light scattering. All these surfactants significantly decreased the particle size, but Gemini was the most effective one to control the calcium phosphonate salt particle size to be about 500 nm. Long-term squeeze experiments (∼3000 PV) saturated with calcite at 70°C and 75 psi back pressure through a glass column packed with Fayetteville shale rock show that the return DTPMP concentration was as high as 3 ppm for the Gemini–Ca-DTPMP colloidal inhibitor. This is an unprecedented improvement in comparison with the squeeze return of DTPMP only inhibitor where the inhibitor return concentration dropped to below 1 ppm within 400 pore volumes. The Ca-DTPMP speciation, potential field application, and the SqueezeSoftPitzer model prediction are also discussed.
Reactions of CO2 with Th+ have been studied using guided ion beam tandem mass spectrometry (GIBMS) and with An+ (An+ = Th+, U+, Pu+, and Am+) using triple quadrupole inductively coupled plasma mass ...spectrometry (QQQ-ICP-MS). Additionally, the reactions ThO+ + CO and ThO+ + CO2 were examined using GIBMS. Modeling the kinetic energy dependent GIBMS data allowed determination of bond dissociation energies (BDEs) for Do(Th+-O) and Do(OTh+-O) that are in reasonable agreement with previous GIBMS measurements. The QQQ-ICP-MS reactions were studied at higher pressures where multiple collisions between An+ and the neutral CO2 occur. As a consequence, both AnO+ and AnO2+ products were observed for all An+ except Am+, where only AmO+ was observed. Here, the relative abundances of the observed monoxides compared to the dioxides are consistent with previous reports of the AnOn+ (n = 1, 2) BDEs. Comparison of the periodic trends of the group 4 transition metal, lanthanide (Ln), and actinide atomic cations in reactions with CO2 (a formally spin-forbidden reaction for most M+ ground states), and O2 (a spin unrestricted reaction) indicate that spin conservation plays a minor role, if any, for the heavier An+ metals. Further correlation of Ln+ and An+ + CO2 reaction efficiencies with the promotion energy (Ep) to the first electronic state with two valence d-electrons (Ep(5d2) for Ln+ and Ep(6d2) for An+) indicates that the primary limitation in the activation of CO2 is the energetic cost to promote from the electronic ground state of the atomic metal ion to a reactive state.
Increased demand for improving ultra-low background detection capabilities for rare-event fundamental physics applications has resulted in the need for fast, convenient and clean assay methodologies ...that either preclude or reduce chemical sample pre-processing. A novel method for the measurement of ultra-trace concentrations (fg g −1 level) of natural 232 Th and 238 U and non-natural tracer isotopes 229 Th and 233 U was demonstrated in a solution of 10 μg g −1 each of Au, Pt, Ir, and W in 2% HNO 3 using an ICP-QQQ-MS. Polyatomic interference across an m / z range of 227–239 was characterized: the major interferent with 229 Th + is 194 Pt 35 Cl + ; interferents with 232 Th + are 184 W 16 O 3 + , 183 W 16 O 3 H + , 192 Pt 40 Ar + , 196 Pt 36 Ar + , 195 Pt 37 Cl + , and 197 Au 35 Cl + ; those with 233 U + are 193 Ir 40 Ar + , 197 Au 36 Ar + , and 184 W 16 O 3 H + ; and that with 238 U + is 198 Pt 40 Ar + . Scanning the selected m / z range of 227–270 showed that higher oxide polyatomic species from the matrix elements either did not form or did not create a significant background on the target analyte masses. All measured concentrations in standard solutions matched the target values within the 98% confidence interval. The Th measurements were 80% accurate or better at the 10 fg g −1 level and above, and the U measurements were 90% accurate or better at the 10 fg g −1 level and above. Measurements at the 1 fg g −1 level were consistent with target values within 1 standard deviation, although the standard deviations of all three replicates were greater than 20% of the measured concentration value. Method detection limits in the matrix solutions were calculated to be 2.74 fg Th and 12.9 fg U. In an electronic sample, which typically has 0.1% precious metal content, our method would give detection limits of 274 fg Th and 1291 fg U given a maximum of 10 μg g −1 coinage metal matrix. This method is but one example of how state-of-the-art quadrupole mass spectrometry and collision reaction cell technology can be leveraged to develop novel analytical capability at ultra-trace levels.
Understanding scale deposition kinetics and the mechanism of inhibition is important for scale prediction and remedial strategies in the energy industry. A novel experimental apparatus was designed ...to understand calcite scale deposition kinetics under relevant industrial conditions and to determine scaling inhibition effects of four phosphonate and two polymer inhibitors. A 1-D transport-reaction model was also developed to conceptually simulate the behavior of the inhibitor within the reaction column following basic laws of advection and adsorption. Inhibition experiments showed that for all phosphonate inhibitors tested and PPCA, the minimum effective inhibitor concentration needed to induce an inhibition effect within a maximum 1 h time frame was also sufficient to achieve 100% inhibition within the column. The exception, CMI, only achieved 80% inhibition. The 1-D transport-reaction model was then used to simulate the experimental data, assuming Langmuirian adsorption of the inhibitor within the column. Preliminary simulations suggest a maximum adsorption of 1–8 mg/m2 for phosphonate inhibitors, indicating that a multilayer adsorption mechanism operates under our experimental conditions.
•A novel flow through apparatus mimicking calcite scale formation as it occurs in oil production pipelines was developed.•A 1D advection-reaction model was developed to interpret deposition kinetics and inhibition in flow through experiments.•Under high salinity and temperature conditions, calcite scale deposition was found to be diffusion controlled.•Langmuirian adsorption is the likely mechanism by which inhibitors attach to scale surfaces and prevent further growth.•Preliminary simulations suggest that a multilayer adsorption mechanism operates under our experimental conditions.
Stirred gypsum (CaSO4·2H2O) precipitation experiments (initial Ωgypsum=2.4±0.14, duration≈1.0–1.5h) were conducted in the presence of the amino acids glycine (190µM), l-alanine (190µM), d- and ...l-arginine (45µM), and l-tyrosine (200µM) to investigate the effect of simple organic compounds on both the precipitation kinetics and Ca isotopic composition of gypsum. Relative to abiotic controls, glycine, tyrosine, and alanine inhibited precipitation rates by ∼22%, 27%, and 29%, respectively, while l- and d-arginine accelerated crystal growth by ∼8% and 48%, respectively. With the exception of tyrosine, amino acid induced inhibition resulted in fractionation factors (αs-f) associated with precipitation that were no more than 0.3‰ lower than amino acid-free controls. In contrast, the tyrosine and d- and l-arginine experiments had αs-f values associated with precipitation that were similar to the controls.
Our experimental results indicate that Ca isotopic fractionation associated with gypsum precipitation is impacted by growth inhibition in the presence of amino acids. Specifically, we propose that the surface-specific binding of amino acids to gypsum can change the equilibrium fractionation factor of the bulk mineral. We investigate the hypothesis that amino acids can influence the growth of gypsum at specific crystal faces via adsorption and that different faces have distinct fractionation factors (αface-fluid). Accordingly, preferential sorption of amino acids at particular faces changes the relative, face-specific mass fluxes of Ca during growth, which influences the bulk isotopic composition of the mineral. Density functional theory (DFT) calculations suggest that the energetic favorability of glycine sorption onto gypsum crystal faces occurs in the order: (110)>(010)>(120)>(011), while glycine sorption onto the (−111) face was found to be energetically unfavorable. Face-specific fractionation factors constrained by frequency calculations of clusters derived from DFT structures vary by as much as 1.4‰. This suggests that the equilibrium fractionation factor for the bulk crystal can vary substantially, and that surface sorption can induce changes in αeq associated with gypsum precipitation. While we do not rule out the influence of kinetic isotope effects, our results clearly demonstrate that the mode of crystal growth can have a sizeable effect on the bulk fractionation factor (αs-f).
Ultimately, our results suggest that the same mechanism by which organic molecules affect the morphology of a mineral can also impact the isotopic composition of the mineral. The results of our study provide valuable insight into the mechanism of Ca isotopic fractionation during gypsum precipitation. Our results are also important for establishing a framework for accurate interpretations of mineral-hosted Ca isotope records of the past, as we demonstrate a mechanistic pathway by which the biological and chemical environment can impact Ca isotopic fractionation during mineral precipitation.
Ultra-low radioactivity Kapton and copper-Kapton laminates Arnquist, Isaac J.; Beck, Chelsie; di Vacri, Maria Laura ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2020, Letnik:
959, Številka:
C
Journal Article
Recenzirano
Odprti dostop
Polyimide-based materials, like Kapton, are widely used in flexible cables and circuitry due to their unique electrical and mechanical characteristics. This study is aimed at investigating the ...radiopurity of Kapton for use in ultralow background, rare-event physics applications by measuring the 238U, 232Th, and natK levels using inductively coupled plasma mass spectrometry. Commercial-off-the-shelf Kapton varieties, measured at approximately 950 and 120 pg/g 238U and 232Th (1.2 × 104 and 490 μBq/kg), respectively, can be a significant background source for many current and next-generation ultralow background detectors. This study has found that the dominant contamination is due to the use of dicalcium phosphate (DCP), a nonessential slip additive added during manufacturing. Alternative Kapton materials were obtained that did not contain DCP and were determined to be significantly more radiopure than the commercially-available options with 12 and 19 pg/g 238U and 232Th (150 and 77 μBq/kg), respectively. The lowest radioactivity version produced (Kapton ELJ, which contains an adhesive) was found to contain single digit pg/g levels of 238U and 232Th, two-to-three orders of magnitude cleaner than commercial-off-the-shelf options. Moreover, copper-clad polyimide laminates employing Kapton ELJ as the insulator were obtained and shown to be very radiopure at 8.6 and 22 pg/g 238U and 232Th (110 and 89 μBq/kg), respectively.
Increased demand for improving ultra-low background detection capabilities for rare-event fundamental physics applications has resulted in the need for fast, convenient and clean assay methodologies ...that either preclude or reduce chemical sample pre-processing. A novel method for the measurement of ultra-trace concentrations (fg g
−1
level) of natural
232
Th and
238
U and non-natural tracer isotopes
229
Th and
233
U was demonstrated in a solution of 10 μg g
−1
each of Au, Pt, Ir, and W in 2% HNO
3
using an ICP-QQQ-MS. Polyatomic interference across an
m
/
z
range of 227-239 was characterized: the major interferent with
229
Th
+
is
194
Pt
35
Cl
+
; interferents with
232
Th
+
are
184
W
16
O
3
+
,
183
W
16
O
3
H
+
,
192
Pt
40
Ar
+
,
196
Pt
36
Ar
+
,
195
Pt
37
Cl
+
, and
197
Au
35
Cl
+
; those with
233
U
+
are
193
Ir
40
Ar
+
,
197
Au
36
Ar
+
, and
184
W
16
O
3
H
+
; and that with
238
U
+
is
198
Pt
40
Ar
+
. Scanning the selected
m
/
z
range of 227-270 showed that higher oxide polyatomic species from the matrix elements either did not form or did not create a significant background on the target analyte masses. All measured concentrations in standard solutions matched the target values within the 98% confidence interval. The Th measurements were 80% accurate or better at the 10 fg g
−1
level and above, and the U measurements were 90% accurate or better at the 10 fg g
−1
level and above. Measurements at the 1 fg g
−1
level were consistent with target values within 1 standard deviation, although the standard deviations of all three replicates were greater than 20% of the measured concentration value. Method detection limits in the matrix solutions were calculated to be 2.74 fg Th and 12.9 fg U. In an electronic sample, which typically has 0.1% precious metal content, our method would give detection limits of 274 fg Th and 1291 fg U given a maximum of 10 μg g
−1
coinage metal matrix. This method is but one example of how state-of-the-art quadrupole mass spectrometry and collision reaction cell technology can be leveraged to develop novel analytical capability at ultra-trace levels.
A mass shift method using ICP-MS/MS with O
2
reaction gas is used for ultra-trace determinations of U and Th in samples containing W, Ir, Pt, and Au derived polyatomic interferants without the need for extensive chemical sample preprocessing.
Reactions of CO2 with Th+ have been studied using guided ion beam tandem mass spectrometry (GIBMS) and with An+ (An+ = Th+, U+, Pu+, and Am+) using triple quadrupole inductively coupled plasma mass ...spectrometry (QQQ-ICP-MS). Additionally, the reactions ThO+ + CO and ThO+ + CO2 were examined using GIBMS. Modeling the kinetic energy-dependent GIBMS data allowed the determination of bond dissociation energies (BDEs) for D 0(Th+–O) and D 0(OTh+–O) that are in reasonable agreement with previous GIBMS measurements. The QQQ-ICP-MS reactions were studied at higher pressures where multiple collisions between An+ and the neutral CO2 occur. As a consequence, both AnO+ and AnO2 + products were observed for all An+ except Am+, where only AmO+ was observed. The relative abundances of the observed monoxides compared to the dioxides are consistent with previous reports of the AnO n + (n = 1, 2) BDEs. A comparison of the periodic trends of the group 4 transition metal, lanthanide (Ln), and actinide atomic cations in reactions with CO2 (a formally spin-forbidden reaction for most M+ ground states) and O2 (a spin-unrestricted reaction) indicates that spin conservation plays a minor role, if any, for the heavier Ln+ and An+ metals. Further correlation of Ln+ and An+ + CO2 reaction efficiencies with the promotion energy (E p) to the first electronic state with two valence d-electrons (E p(5d2) for Ln+ and E p(6d2) for An+) indicates that the primary limitation in the activation of CO2 is the energetic cost to promote from the electronic ground state of the atomic metal ion to a reactive state.
Reactions of CO
with Th
have been studied using guided ion beam tandem mass spectrometry (GIBMS) and with An
(An
= Th
, U
, Pu
, and Am
) using triple quadrupole inductively coupled plasma mass ...spectrometry (QQQ-ICP-MS). Additionally, the reactions ThO
+ CO and ThO
+ CO
were examined using GIBMS. Modeling the kinetic energy-dependent GIBMS data allowed the determination of bond dissociation energies (BDEs) for
(Th
-O) and
(OTh
-O) that are in reasonable agreement with previous GIBMS measurements. The QQQ-ICP-MS reactions were studied at higher pressures where multiple collisions between An
and the neutral CO
occur. As a consequence, both AnO
and AnO
products were observed for all An
except Am
, where only AmO
was observed. The relative abundances of the observed monoxides compared to the dioxides are consistent with previous reports of the AnO
(
= 1, 2) BDEs. A comparison of the periodic trends of the group 4 transition metal, lanthanide (Ln), and actinide atomic cations in reactions with CO
(a formally spin-forbidden reaction for most M
ground states) and O
(a spin-unrestricted reaction) indicates that spin conservation plays a minor role, if any, for the heavier Ln
and An
metals. Further correlation of Ln
and An
+ CO
reaction efficiencies with the promotion energy (
) to the first electronic state with two valence
-electrons (
(5d
) for Ln
and
(6d
) for An
) indicates that the primary limitation in the activation of CO
is the energetic cost to promote from the electronic ground state of the atomic metal ion to a reactive state.
Experiments investigating Ca isotopic fractionation during gypsum precipitation were undertaken in order to elucidate the mechanisms and conditions that govern isotopic fractionation during mineral ...precipitation. Both stirred and unstirred free drift gypsum precipitation experiments were conducted at constant initial ionic strength (0.6M) and variable initial saturation states (4.8–1.5) and Ca2+:SO42− ratios (3 and 0.33). Experimental durations varied between 0.5 and 190h, while temperature (25.9–24.0°C), pH (5.8–5.4) and ionic strength (0.6–0.5) were relatively constant. In all experiments, 20–80% of the initial dissolved Ca reservoir was precipitated. Isotopically light Ca preferentially partitioned into the precipitated gypsum; the effective isotopic fractionation factor (Δ44/40Cas–f=δ44/40Casolid−δ44/40Cafluid) of the experimental gypsum ranged from −2.25‰ to −0.82‰. The log weight-averaged, surface area normalized precipitation rates correlated with saturation state and varied between 4.6 and 2.0μmol/m2/h. The crystal size and aspect ratios, determined by SEM images, BET surface area, and particle size measurements, co-varied with precipitation rate, such that fast growth produced small (10–20μm), tabular crystals and slow growth produced larger (>1000μm), needle shaped crystals.
Mass balance derived δ44Cas and Δ44Cas–f, calculated using the initial fluid δ44Ca and the mass fraction of Ca removed during precipitation (fCa) as constraints, suggest that the precipitate was not always sampled homogeneously due to the need to preserve the sample for SEM, surface area, and particle size analyses. The fractionation factor (αs–f), derived from Rayleigh model fits to the fluid and calculated bulk solid, ranged from 0.9985 to 0.9988 in stirred experiments and 0.9987 to 0.9992 in unstirred experiments. The αs–f demonstrated no clear dependence on either precipitation rate or initial saturation state in stirred reactors, but exhibited a positive dependence on rate in unstirred experiments. The differences in αs–f between stirred and unstirred reactors, as well as a general correlation between αs–f and crystal morphology, led us to hypothesize that growth on different crystal faces controls the isotopic composition of gypsum. We also explore the idea that speciation in solution explains the difference between experiments in which the only major difference was the Ca2+ to SO42− ratio in solution.
The importance of understanding the environmental controls on the fractionation factor during mineral precipitation is highlighted in this study. The fractionation factor of gypsum precipitation near chemical equilibrium was found to be ∼0.9995, rather than 1, indicating that even at near equilibrium conditions, the δ44Ca of minerals are not likely to record the δ44Ca of the solution directly. However, the measurable isotopic fractionation associated with gypsum formation does suggest that a gypsum-based proxy may be useful in constraining Ca cycling in marginal environments over geologic time scales. Model examples are provided that demonstrate how such a proxy would operate.
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