Effect of fly ash addition on the removal of hydrogen sulfide from biogas and air on sewage sludge-based composite adsorbents

Desulfurization adsorbents were prepared from the mixtures of various compositions of New York City sewage sludge and fly ashes from SASOL, South Africa, by pyrolysis at 950 degrees C. The resulting materials were used as adsorbents of hydrogen sulfide from simulated dry digester gas mixture or moist air. The adsorbents before and after H(2)S removal were characterized using adsorption of nitrogen, elemental analysis, pH measurements, XRF, XRD, and thermal analysis. It was found that the addition of fly ash decreases the desulfurization capacity in comparison with the sewage sludge-based materials. The extent of this decrease depends on the type of ash, its content and the composition of challenging gas. Although the presence of CO(2) deactivates some adsorption sites to various degrees depending on the sample composition, the addition of ashes has a more detrimental effect when the adsorbents are used to remove hydrogen sulfide from air. This is likely the result of hydrophobicity of ashes since the H(2)S removal capacity was found to be strongly dependent on the reactivity towards water/water adsorption. On the other hand, the addition of ashes strongly decreases the porosity of materials where sulfur, as a product of hydrogen sulfide oxidation, can be stored.     

Quantifying greenhouse gas emissions

Mitigation and Adaptation Strategies for Global Change - The assessment of greenhouse gases (GHGs) and air pollutants emitted to and removed from the atmosphere ranks high on international...     

The sensitivity of the costs of reducing emissions from deforestation and degradation (REDD) to future socioeconomic drivers and its implications for mitigation policy design

Mitigation and Adaptation Strategies for Global Change - Climate change mitigation policies for the land use, land use change, and forestry (LULUCF) sector are commonly assessed based on marginal...     

Environmental concentrations of Roundup in combination with chlorpromazine or heating causes biochemical disturbances in the bivalve mollusc Unio tumidus

Environmental Science and Pollution Research - Bivalve molluscs represent the most recognized bioindicators of freshwater pollution. However, their ability to indicate specific xenobiotics in...