The role of reversible and polarizable surface charge in the electro-sorption of NaCl electrolyte onto activated carbon-graphite electrode

Abstract This study examined the effect of polyphosphate on removal of endocrine-disrupting chemicals (EDCs) such as nonylphenol and bisphenol-A by activated carbons. It was found that polyphosphate aided in the removal of nonylphenol and bisphenol- A. Polyphosphate reacted with nonylphenol, likely through dipole-dipole interaction, which then improved the nonylphenol removal. Calcium interfered with this reaction by causing competition. It was found that polyphosphate could accumulate on carbon while treating a river. The accumulated polyphosphate then aided nonylphenol removal. The extent of accumulation was dependent on the type of carbon. The accumulation occurred more extensively with the wood-based used carbon than with the coal-based used carbon due to the surface charge of the carbon. The negatively charged wood-based carbon attracted the positively charged calcium-polyphosphate complex more strongly than the uncharged coal-based carbon. The polyphosphate-coated activated carbon was also effective in nonylphenol removal. The effect was different depending on the type of carbon. Polyphosphate readily attached onto the wood-based carbon due to its high affinity for polyphosphate. The attached polyphosphate then improved the nonylphenol removal. However, the coating failed to attach polyphosphate onto the coal-based carbon. The nonylphenol removal performance of the coal-based carbon remained unchanged after the polyphosphate coating.

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Role of CO2 During Oxidative Dehydrogenation of Propane Over Bulk and Activated-Carbon Supported Cerium and Vanadium Based Catalysts

Catalysis Letters ◽

10.1007/s10562-020-03519-y ◽

2021 ◽

Author(s):

Petar Djinović ◽

Janez Zavašnik ◽

Janvit Teržan ◽

Ivan Jerman

Keyword(s):

Catalytic Activity ◽

Activated Carbon ◽

Oxidative Dehydrogenation ◽

Active Phase ◽

Lattice Oxygen ◽

Chemisorbed Oxygen ◽

Catalytically Active ◽

Temperature Programmed ◽

Propane Cracking

AbstractCeO2, V2O5 and CeVO4 were synthesised as bulk oxides, or deposited over activated carbon, characterized by XRD, HRTEM, CO2-TPO, C3H8-TPR, DRIFTS and Raman techniques and tested in propane oxidative dehydrogenation using CO2. Complete oxidation of propane to CO and CO2 is favoured by lattice oxygen of CeO2. The temperature programmed experiments show the ~ 4 nm AC supported CeO2 crystallites become more susceptible to reduction by propane, but less prone to re-oxidation with CO2 compared to bulk CeO2. Catalytic activity of CeVO4/AC catalysts requires a 1–2 nm amorphous CeVO4 layer. During reaction, the amorphous CeVO4 layer crystallises and several atomic layers of carbon cover the CeVO4 surface, resulting in deactivation. During reaction, V2O5 is irreversibly reduced to V2O3. The lattice oxygen in bulk V2O5 favours catalytic activity and propene selectivity. Bulk V2O3 promotes only propane cracking with no propene selectivity. In VOx/AC materials, vanadium carbide is the catalytically active phase. Propane dehydrogenation over VC proceeds via chemisorbed oxygen species originating from the dissociated CO2. Graphic Abstract

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Overcoming ammonia inhibition in anaerobic blackwater treatment with granular activated carbon: the role of electroactive microorganisms

Environmental Science Water Research & Technology ◽

10.1039/c8ew00599k ◽

2019 ◽

Vol 5 (2) ◽

pp. 383-396 ◽

Cited By ~ 19

Author(s):

Anna Patrícya Florentino ◽

Ahmed Sharaf ◽

Lei Zhang ◽

Yang Liu

Keyword(s):

Activated Carbon ◽

Hydrogen Exchange ◽

Granular Activated Carbon ◽

Ammonia Concentration ◽

Anaerobic Digesters ◽

Ammonia Inhibition ◽

High Ammonia

Methanogenesis and enrichment of microorganisms capable of interspecies electron and/or hydrogen exchange was investigated with addition of granular activated carbon (GAC) to batch anaerobic digesters treating vacuum collected blackwater with high ammonia concentration.

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