Search results for "Flue-gas desulfurization"
showing 8 items of 8 documents
Fully aerobic bioscrubber for the desulfurization of H2S-rich biogas
2019
Abstract A fully aerobic bioscrubber for the desulfurization of H2S-rich biogas was developed in the present study by coupling an absorption column and a bubble column bioreactor. The bioscrubber treated H2S loading rates of 37, 59, and 100 g S mliquid−3 h−1 at gas residence times of 6.6, 4.1 and 2.4 min in the absorption column, respectively. Stable H2S removal efficiencies above 80% were recorded at all the conditions tested. The bioscrubber was robust towards short- and long-term operation shutdowns (5 and 18 days), the H2S removal performance being recovered after few hours. The aerated bubble column bioreactor was operated at slightly alkaline conditions (pH 8 ± 0.5), which prevented H…
Desulfurization: Critical step towards enhanced selenium removal from industrial effluents
2017
Abstract Selenium (Se) removal from synthetic solutions and from real Flue Gas Desulfurization (FGD) wastewater generated by a coal-fired power plant was studied for the first time using a commercial iron oxide impregnated strong base anion exchange resin, Purolite ® FerrIX A33E. In synthetic solutions, the resin showed high affinity for selenate and selenite, while sulfate exhibited a strong competition for both oxyanions. The FGD wastewater investigated is a complex system that contains Se (∼1200 μg L −1 ), SO 4 2− (∼1.1 g L −1 ), Cl − (∼9.5 g L −1 ), and Ca 2+ (∼5 g L −1 ), alongside a broad spectrum of toxic trace metals including Cd, Cr, Hg, Ni, and Zn. The resin performed poorly again…
Bacterial community analysis of a gas-phase biotrickling filter for biogas mimics desulfurization through the rRNA approach
2010
Abstract The bacterial composition of a lab-scale biotrickling filter (BTF) treating high loads of H 2 S was investigated by the rRNA approach. Two 16S rRNA gene clone libraries were established 42 and 189 d after reactor startup, while fluorescent in-situ hybridization (FISH) with DNA probes was performed throughout 260 d of reactor operation. Diversity, community structure and metamorphosis were studied from reactor startup to fully-established pseudo-steady state operation at near neutral pH and at an inlet H 2 S concentration of 2000 ppmv (load of 55.6 g H 2 S m −3 h −1 ). In addition, FISH was used for assessing the spatial distribution of sulfur-oxidizing bacteria (SOB) along the len…
Sulfidation Mechanism of Pure and Cu-Doped ZnO Nanoparticles at Moderate Temperature: TEM and In Situ XRD Studies
2012
International audience; Sulfidation mechanism of pure and Cu-doped ZnO nanoparticles (Cu0.03Zn0.97O and Cu0.06Zn0.94O) at 250 and 350 degrees C was studied by transmission electron microscopy (TEM) and in situ synchrotron XRD. For nondoped ZnO, we observed by TEM that partial reaction with H2S is accompanied by the formation of voids at the ZnO/ZnS interface. This phenomenon (known as the Kirkendall effect) confirms that sulfidation of nanosized ZnO by gaseous H2S proceeds via the outward growth of ZnS: Zn2+ and O2- are transferred to the external (ZnS/gas) surface, where zinc is combined with sulfur and oxygen reacts with protons yielding H2O. During sulfidation of Cu-doped ZnO, the caviti…
Kinetics of thiophene reactive adsorption on Ni/SiO2 and Ni/ZnO.
2008
Abstract Kinetics of thiophene reactive adsorption on Ni/SiO2 and Ni/ZnO was studied by thermal gravimetric analysis at 280–360 °C under 5–40 mbar of thiophene in H2. In the case of Ni/SiO2 the interaction proceeds in two steps: a rapid surface reaction is followed by a slower bulk transformation into Ni3S2. Maximum Ni conversion depends on reaction conditions and observed conversion profiles can be described by an exponential equation corresponding to a reaction of first order relatively to both sulfidable Ni amount and thiophene. The interaction between Ni/ZnO and thiophene proceeds in a rather different manner. A rapid increase of weight, similar to the first stage observed on Ni/SiO2, i…
STUDIEN ZUM VORGANG DER WASSERSTOFFÜBERTRAGUNG 731HYDROGENOLYSESTUDIEN VON SCHWEFEL-UND PHOSPHOR-VERBINDUNGEN AN RANEY-NICKEL (Ra-Ni)—EINE MATERIALSA…
1985
Abstract The desulfurization and dephosphorization with Raney-Nickel (Ra-Ni) is investigated under standard conditions using the following types of compounds: Mercaptanes. thioethers, di- and trisulfides, sulfonium salts, sulfoxides, sulfones, sulfonic acid derivatives, bidental thioethers before and after the chelation, tertiary phosphines and phosphites, phosphonium salts and amidophosphonium salts, phosphine-metal-complexes, model compounds containing sulfur and phosphorus in the same molecule and samples of aerosil the surface of which is modified with S- and P-functions. The degree of the desulfurization and dephosphorization is dependent on the amount and availability of the “structur…
Wo3 and ionic liquids: A synergic pair for pollutant gas sensing and desulfurization
2020
This review deals with the notable results obtained by the synergy between ionic liquids (ILs) and WO3 in the field of pollutant gas sensing and sulfur removal pretreatment of fuels. Starting from the known characteristics of tungsten trioxide as catalytic material, many authors have proposed the use of ionic liquids in order to both direct WO3 production towards controllable nanostructures (nanorods, nanospheres, etc.) and to modify the metal oxide structure (incorporating ILs) in order to increase the gas adsorption ability and, thus, the catalytic efficiency. Moreover, ionic liquids are able to highly disperse WO3 in composites, thus enhancing the contact surface and the catalytic abilit…
Preparation of tungstophosphoric acid/cerium-doped NH2-UiO-66 Z-scheme photocatalyst: a new candidate for green photo-oxidation of dibenzothiophene a…
2021
International audience; The goal of this study was to introduce an effective visible-light induced photocatalytic system with a good ability for photocatalytic oxidative desulfurization (PODS) and denitrogenation (PODN) using molecular oxygen (O2) as an oxidant. In this regard, tungestophosphoric acid (PW12) was supported onto cerium-doped NH2-UiO-66 (PW12/Ce-NUiO-66) and employed for the photo-oxidation of dibenzothiophene (DBT) and quinoline (Qu). Herein, using cerium (Ce) as a “mediator” facilitated the separation of charge carriers, while NH2-UiO-66 remarkably enhanced the surface area with plentiful adsorption sites and shifted the adsorption edge of PW12to the visible region. The sum …