Influence of aluminium impregnation on activated carbon for enhanced desulfurization of DBT at ambient temperature: Role of surface acidity and textural properties

This paper focuses on the valorisation of solid residues obtained from the thermal treatment of sewage sludge. In particular, sewage sludge samples were collected from two waste water treatment plants (WWTPs) with different sludge line basic operations. After drying, sludges were heated up to 700 °C in appropriate ovens under diluted air (gasification) and inert (pyrolysis) atmospheres. The solids obtained, as well as the dried (raw) sludges, were characterised to determine their textural properties and chemical composition, including the speciation of their inorganic fraction. All the materials under study were employed as adsorbents/catalysts in H2S removal experiments at room temperature. It was found that, depending on the particular sludge characteristics, outstanding results can be achieved both in terms of retention capacities and selectivity. Some of the solids outperform commercially available sorbents specially designed for gaseous emissions control. In these adsorbents/catalysts, H2S is selectively oxidised to elemental sulphur most likely due to the presence of inorganic, catalytically active species. The role of the carbon-enriched part on these solids is also remarked.

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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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Role of fever and ambient temperature in COVID-19

Expert Review of Respiratory Medicine ◽

10.1080/17476348.2020.1816172 ◽

2020 ◽

pp. 1-3

Author(s):

Muhammad Hamdan Gul ◽

Zin Mar Htun ◽

Asad Inayat

Keyword(s):

Ambient Temperature

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Characterization and Catalytic Behaviour of Co3(PO4)2–AlPO4 Catalysts

Adsorption Science & Technology ◽

10.1177/026361749801600405 ◽

1998 ◽

Vol 16 (4) ◽

pp. 285-293 ◽

Cited By ~ 5

Author(s):

M.R. Mostafa ◽

F.Sh. Ahmed

Keyword(s):

Pore Radius ◽

Surface Acidity ◽

Total Pore Volume ◽

Textural Properties ◽

Acid Sites ◽

Adsorption Of Nitrogen ◽

Amorphous Structures ◽

Ft Ir ◽

Catalytic Behaviour ◽

The Mean

Co3(PO4)2, AlPO4 and the binary system Co3(PO4)2-AlPO4 with different compositions were prepared by the coprecipitation method. The structural properties of these samples were determined using XRD, DTA and FT-IR techniques. The textural properties were determined from the adsorption of nitrogen at 77 K. The surface acidity was measured by a calorimetric titration method. The samples were tested as catalysts in the dehydration of ethanol and isopropanol using a pulse microcatalytic technique. The data obtained from XRD and FT-IR indicate the amorphous structures of the prepared catalysts. An increase in Co3(PO4)2 content led to a decrease in the surface area and in the total pore volume and an increase in the mean pore radius. The surface acidity of the catalyst depends on the chemical composition; the surface acidity increased with an increase in the AlPO4 content. The dehydration temperature and the distribution of acid sites are important parameters in determining the selectivity and activity of the catalyst.

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