Biochemical processes by chemoautotrophs such as nitrifiers and sulfide and iron oxidizers are used extensively in wastewater treatment. The research described in this dissertation involved the study of two selected biological processes utilized in wastewater treatment mediated by chemoautotrophic bacteria: nitrification (biological removal of ammonia and nitrogen) and hydrogen sulfide (H2S) re...

The modified Claus process is the major technology for the recovery of elemental sulfur from hydrogen sulfide. The chemical reactions that can occur in the reaction furnace are numerous and many byproducts such as carbon disulfide and carbon carbonyl sulfide are produced. These compounds can often contribute from 20 to 50% of the pollutants and therefore, should be hydrolyzed in the catalytic c...

A 20-month pilot-scale study was conducted to examine the impact of temperature on the performance of an anaerobic biological contractor used to treat perchlorate-contaminated water. The contractor was successfully acclimated with indigenous microorganisms. Influent temperatures varied from 1.4 to 30 degrees C. The objectives of the study were to investigate the effects of temperature on perchl...

Molybdenum sulfide (MoS2) is widely recognized for its catalytic activities where the edges of the crystals turn over reactions. Generating sulfur defects on the basal plane of MoS2 can improve its catalytic activity, but generally there is a lack of model system for understanding metal-centered catalysis on the basal planes. Here, we synthesized a new phase of sub-stoichiometric molybdenum sul...

In this study, photocatalytic degradation of diazinon was investigated using commercial nano-TiO2as a photocatalyst the operational parameters such as adsorption, aeration, pH and nano-TiO2 dosage were investigated. Dispersive liquid-liquid microextraction (DLLME) technique was used to extract and preconcentration of residual diazinon and by-products from the liquid samples and the analysis was...

"Thioalkalivibrio sulfidophilus" HL-EbGr7 is an obligately chemolithoautotrophic, haloalkaliphilic sulfur-oxidizing bacterium (SOB) belonging to the Gammaproteobacteria. The strain was found to predominate a full-scale bioreactor, removing sulfide from biogas. Here we report the complete genome sequence of strain HL-EbGr7 and its annotation. The genome was sequenced within the Joint Genome Inst...

Sulfide is a common product of marine anaerobic respiration, and a potent reactant biologically and geochemically. Here we demonstrate the impact on microbial communities with the removal of sulfide via electrochemical methods. The use of differential pulse voltammetry revealed that the oxidation of soluble sulfide was seen at +30 mV (vs. SHE) at all pH ranges tested (from pH = 4 to 8), while n...

The present XANES study aims at elucidating the roles of carbon deposits and metal sulfides in the catalyst deactivation in steam reforming reactions with the presence of sulfur. CeO(2)-Al(2)O(3)-supported Ni and Rh-based catalysts were tested in steam reforming of liquid hydrocarbon fuel containing 350 ppm sulfur for H(2) production at 800 degrees C. The Rh catalyst demonstrated much better su...

The paper provides an overview of natural radionuclides in surface water and groundwater, their maximum permissible concentrations, health effects, different processes of removal (aeration, coagulation and co-precipitation, filtration, adsorption, ion exchange, membrane separation), treatment costs, and options of radioactive waste management.

One of the important components quality food products is water used. A common way to remove unwanted impurities from aeration, i.e. oxidation chemical compounds in by oxygen. Aeration devices with mechanical energy input comparison other groups devices, namely gas phase and liquid phase, have low power consumption additional mixing processed medium. The work presents a study oxygen absorption a...