Oxygen permeation through teflon–PFA tubing into flowing argon

Giacobbe, F. W.

doi:10.1002/app.1992.070460621

Cited by 6 publications

(5 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After 12 days, the readily available organic matter seemed to be depleted and could not donate electrons to sufficiently compensate the inflow of oxygen that was presumed to diffuse through the Teflon tubing into the system (Giacobbe 1992 ; Peirce 1958 ). This is supported by the observation that the redox potential of the inflow is continuously higher than the redox potential of the outflow.…”

Section: Discussionmentioning

confidence: 99%

Combination of aquifer thermal energy storage and enhanced bioremediation: resilience of reductive dechlorination to redox changes

Gaans

Smit

et al. 2015

Appl Microbiol Biotechnol

View full text Add to dashboard Cite

To meet the demand for sustainable energy, aquifer thermal energy storage (ATES) is widely used in the subsurface in urban areas. However, contamination of groundwater, especially with chlorinated volatile organic compounds (CVOCs), is often being encountered. This is commonly seen as an impediment to ATES implementation, although more recently, combining ATES and enhanced bioremediation of CVOCs has been proposed. Issues to be addressed are the high water flow velocities and potential periodic redox fluctuation that accompany ATES. A column study was performed, at a high water flow velocity of 2 m/h, simulating possible changes in subsurface redox conditions due to ATES operation by serial additions of lactate and nitrate. The impacts of redox changes on reductive dechlorination as well as the microbial response of Dehalococcoides (DHC) were evaluated. The results showed that, upon lactate addition, reductive dechlorination proceeded well and complete dechlorination from cis-DCE to ethene was achieved. Upon subsequent nitrate addition, reductive dechlorination immediately ceased. Disruption of microorganisms’ retention was also immediate and possibly detached DHC which preferred attaching to the soil matrix under biostimulation conditions. Initially, recovery of dechlorination was possible but required bioaugmentation and nutrient amendment in addition to lactate dosing. Repeated interruption of dechlorination and DHC activity by nitrate dosing appeared to be less easily reversible requiring more efforts for regenerating dechlorination. Overall, our results indicate that the microbial resilience of DHC in biosimulated ATES conditions is sensitive to redox fluctuations. Hence, combining ATES with bioremediation requires dedicated operation and monitoring on the aquifer geochemical conditions.Electronic supplementary materialThe online version of this article (doi:10.1007/s00253-015-7241-6) contains supplementary material, which is available to authorized users.

show abstract

Section: Discussionmentioning

confidence: 99%

Combination of aquifer thermal energy storage and enhanced bioremediation: resilience of reductive dechlorination to redox changes

Gaans

Smit

et al. 2015

Appl Microbiol Biotechnol

View full text Add to dashboard Cite

show abstract

“…As mentioned above, we expect that polar sites are formed due to the leakage of O 2 into the reactor 13–15 along with the formation of free radicals due to crushing silica by the rocking action of the reactor. 16 Previous reports have shown that hot H 2 gas is capable of reducing oxidized carbon surfaces.…”

Section: Resultsmentioning

confidence: 92%

Improved Synthesis of Carbon-Clad Silica Stationary Phases

Ahmad

Carr

2013

Anal. Chem.

View full text Add to dashboard Cite

Previously we described a novel method for clading elemental carbon onto the surface of catalytically activated silica by a chemical vapor deposition (CVD) method using hexane as the carbon source and its use as a substitute for carbon clad zirconia.1,2 In that method, we showed that very close to exactly one uniform monolayer of Al (III) was deposited on the silica by a process analogous to precipitation from homogeneous solution in order to preclude pore blockage. The purpose of the Al(III) monolayer layer is to activate the surface for subsequent CVD of carbon. In this work, we present an improved procedure for preparing the carbon clad silica (denoted CCSi) phases along with a new column packing process. The new method yields CCSi phases having better efficiency, peak symmetry and higher retentivity compared to carbon clad zirconia. The enhancements were achieved by modifying the original procedure in three ways: first. the kinetics of the deposition of Al(III) were more stringently controlled, second the CVD chamber was flushed with a mixture of hydrogen and nitrogen gas during the carbon cladding process to minimize generation of polar sites by oxygen incorporation, and third the fine particles generated during the CVD process were exhaustively removed by flotation in an appropriate solvent.

show abstract

“…Elevated temperatures do not only influence the structural robustness but also the permeability of polymeric materials, which is typically neglectable at room temperature but rises with increasing temperature [19][20][21]. Permeation P in those materials is typically associated with the solution-diffusion mechanism, which considers the polymeric material as a solid phase with a certain solubility S g and diffusivity D g for, e.g., gaseous components [22].…”

Section: Permeabilitymentioning

confidence: 99%

Polymeric Reactors for Catalytic Reactions beyond Earth

Friedland,

Güttel

2024

Chemie Ingenieur Technik

View full text Add to dashboard Cite

Current space missions to Luna and Mars are considering to use the resources, which can be found on‐site at the destination. This strategy named in‐situ resource utilization (ISRU) saves valuable pay‐load capacities during the rocket launch from the earth surface. Specifically, in mars missions it is intended to produce the necessary rocket fuel CH4 for the back‐transit to earth via water electrolysis and subsequent CO2 methanation. The present study elaborates this concept and examines the question if polymeric reactors are feasible for heterogeneously catalyzed reactions in applications beyond earth. The study aims at providing a theoretical backbone for a proof‐of‐concept. The evaluation is conducted theoretically by design considerations and adds experimental results to show the general feasibility of polymeric reactors for applicable reaction conditions.

show abstract

Oxygen permeation through teflon–PFA tubing into flowing argon

Cited by 6 publications

References 10 publications

Combination of aquifer thermal energy storage and enhanced bioremediation: resilience of reductive dechlorination to redox changes

Combination of aquifer thermal energy storage and enhanced bioremediation: resilience of reductive dechlorination to redox changes

Improved Synthesis of Carbon-Clad Silica Stationary Phases

Polymeric Reactors for Catalytic Reactions beyond Earth

Contact Info

Product

Resources

About