Bernard Manowitz

Sulfonates: A novel class of organic sulfur compounds in marine sediments

Abstract X-ray absorption near-edge structure spectroscopy (XANES) used to measure sulfur speciation in a variety of organic-rich marine sediments has established sulfonates as a novel and major component of sedimentary organic sulfur. The origins of sulfonates in sediments are not clear, although both biological and geochemical mechanisms are possible. The accumulation of oxidized sulfonate sulfur in reducing marine sediments was not known previously; hence, a new perspective in sulfur geochemistry is established. The biogeochemical implications of the presence of sulfonates in marine sediments are discussed.

Formation and diagenesis of macromolecular organic sulfur in Peru margin sediments

Abstract The geochemistry of organic sulfur in a suite of samples covering the upper 100 m of sediment from the Peruvian margin has been characterized by elemental analysis, X-ray absorption (XANES) spectroscopy and analytical pyrolysis. These data are compared with those obtained from a thermally immature, but consolidated, sulfur-rich sediment (Miocene Monterey Fm, CA). Results indicate that sulfur incorporation into organic matter takes place primarily within the upper few meters of sediment, but sulfur “in-growth” continues at greater depths. The major initial products are organic sulfides, with subordinate amounts of thiophenes. Sulfonic acids also comprise a significant portion of the organically-bound sulfur in the shallowest sediments. Analysis of chemically defined organic matter sub-fractions isolated from a surficial (

Oxidation state of sulfur in thiosulfate and implications for anaerobic energy metabolism

Abstract Disproportionation of thiosulfate is an important pathway in bacterial energy metabolism in anoxic sediments. It has been described as an inorganic fermentation process in which a part of the molecule is oxidized to sulfate, while the other stoichiometrically equivalent part is used as electron acceptor and reduced to sulfide. However, an intramolecular redox change is difficult to envisage because, according to the currently held view, the two sulfur atoms of thiosulfate exist in the oxidation state of sulfate (+6) and sulfide (−2) and do not change their respective oxidation states upon disproportionation. Our results based on XANES spectroscopy indicate that the two different sulfur atoms in thiosulfate have charge densities corresponding to +5 and −1 oxidation states which support a redox mechanism in the disproportionation of thiosulfate to sulfate and sulfide.

On the usefulness of sulfur isotope ratios in crude oil correlations

Sulfur isotope analyses have been completed for twelve samples of marine Jurassic oils from a single basin, and are presented along with previous chemical analyses of the same oils (Seifert and Moldowan, 1978). Two isotopic anomalies are discussed in light of correlational analyses, and show that sulfur isotope ratios, when used with other chemical variables, are sensitive indicators of subtle changes in initial source input. Measurements of δ34S in correlational studies of crude oil characterization and identification are recommended.

Interactions of thiols with sedimentary particulate phase: studies of 3-mercaptopropionate in salt marsh sediments from Shelter Island, New York

Abstract 3-Mercaptopropionate (3-MPA) is a major hydrophilic thiol in salt marsh sediments from Shelter Island, New York. It is associated mainly with the sedimentary particulate phase, although the mechanism of its binding has not been clear. In this study, we show that humic substances coated on clay minerals are involved in binding 3-MPA through di- and poly-sulfide linkages. With increasing depth, the abundance of 3-MPA in the fulvic acid fraction decreases with a concomitant increase in the humic acid fraction, suggesting that, with depth, fulvic-bound 3-MPA is converted into humic-bound 3-MPA. We modeled the depth variation with a multi-G model which suggests that there are two types of reactive components in both fulvic acid-bound and humic acid-bound 3-MPA, one changing about 10 times more rapidly than the other. These two 3-MPA pools probably reflect different types of sulfur bridging, with the polysulfide-bridged pool changing more rapidly than the disulfide-bridged pool. As free thiol, 3-MPA is attacked relatively rapidly by anaerobic bacteria, its degradation following firstorder kinetics. However, in the sediment core we studied, humic-bound 3-MPA was present throughout the sediment column, down to 22 cm, corresponding to an age of about 90 years. These results suggest that thiols can escape bacterial degradation in sediments by binding to humic substances. The sedimentary distribution of 3-MPA is an important illustration of the interplay of biological and chemical processes in the fate of thiols in anoxic marine sediments.

The significance of chemical markers in the bioprocessing of fossil fuels

Abstract Biochemical conversion of crude oils is a multi-step process proceeding through a series of biochemical reactions. These reactions can be characterized by a set of chemical markers which are associated with the chemical composition of crude oils. Reactions with heavy crude oils indicate that there is an overall decrease in the concentration and chemical speciation of organic sulfur compounds, and a redistribution of hydrocarbons and organometallic species. The contents of trace metals in the crude oils, such as nickel and vanadium, also decrease. Further, heavy ends of crudes, containing the asphaltenes and the polar nitrogen, sulfur, and oxygen containing fractions, as well as the organometallic compounds and complexes, are biochemically converted to lower molecular weight chemical species. In the studies reported in this paper, microorganisms used to mediate such reactions were thermophilic (> 60°C) and pressure tolerant (up to 2500 psi). These organisms are also capable of biochemical conversion of bituminous and lignite coals in an analogous manner to their action on crude oils and follow similar trends characterized by chemical markers. For example, X-ray absorption near-edge structural (XANES) analyses of biotreated crude oils and low grade coals show that biochemical reactions lead to decreases in organic sulfides and thiophenes with a concurrent increase in sulfoxide contents. Chemically related constituents present in heavy crude oil fractions and low grade coals are the asphaltenes. Asphaltenes are complex structures containing heteroatoms and metals involved in inter- and intra-molecular bridges and stereochemical configurations. The chemical markers associated with the biochemical conversion of oils and coals indicate multiple biochemical processes involving chemical reactions at sites containing heteroatoms and metals leading to a breakdown of the structure(s) to smaller molecular weight units. Thus, using chemical markers as diagnostic tools, the extent and the efficiency of fossil fuel bioconversion may be predicted and monitored, allowing for better cost-efficient field trials. Recent results in this area will be presented and discussed in this paper.

Biodegradation of coals

Abstract Selected strains of bacteria [from the Brookhaven National Laboratory (BNL) collection], capable of degrading heavy crude oils, were used to treat bituminous and lignite coals. Products resulting from biochemical reactions among several microorganisms and different coals were examined by pyrolysis gas chromatography-mass spectrometry (Py. g.c.-m.s.), and X-ray absorption near edge structure (XANES) spectroscopy. The results indicated considerable variations in the organic sulfur as well as modifications in coal structure. Furthermore, biochemical reactions involved in the microbial interactions with coals appeared to be microbial species dependent.

The importance of sulfur isotope ratios in the differentiation of Prudhoe Bay crude oils

Sulfur isotopic analyses have been completed for eight Triassic, Jurassic and Lower Cretaceous oils from the Prudhoe Bay field, Alaska. Results presented complement earlier work and further indicate the diagnostic importance of δ 34S values in correlation studies of crude oils. The present work supports an earlier contention that Kuparuk River, Sadlerochit and Lisburne crude oils have a similar source of origin, distinct from that of Kingak oil. If Kingak and Shublik Formations contribute to the Sag River Sand crude oil in the Prudhoe Bay area of Alaska, the same may not be the case for Sag River Sand oil in the Point Barrow area which apparently originated from a different source or combination of sources.

Chemical markers of induced microbial transformations in crude oils

Abstract Biochemical processes associated with the interactions of acidophilic and pressure-adapted thermophilic or thermoadapted microorganisms suitable for enhanced oil recovery produce characteristic chemical markers. These markers indicate the extent and the nature of chemical alterations of crude oils by microorganisms which have been experimentally introduced and grown in crude oils. The chemical markers include high and low molecular-weight species, organic sulfur compounds, trace metals, and the extent of emulsification. Most recent results suggest that the distribution of major groups of compounds, i.e., the asphaltenes, maltenes, and saturates are also biochemically altered. Experimental evidence indicates that multiple biochemical reactions are involved in the microbial interactions with crude oils. The chemical markers associated with these biochemical reactions are described and discussed in terms of their significance and applicability to the biotreatment of crude oils and enhanced oil recovery.

Treatment and Disposal of Wastes in Nuclear Chemical Technology

Publisher Summary The problems of radiochemical waste disposal are many and varied. The present developments in nuclear energy are such, that with the passage of time, the radiation background will be raised significantly by radiation sources of mans own making, if these are not controlled. The National and International Committees on radiation protection have agreed upon maximum permissible concentrations of radioisotopes in air and water for continuous exposure. It is strongly recommended that every effort be made to reduce exposures to all types of ionizing radiations to the lowest possible level. A number of attempts have been made to assess the magnitude of the disposal problem the world may face during the next half century. Estimates tend to agree that the maximum plausible use of nuclear energy will result in the burn up of approximately 1000 tons of fissionable material, and the production of 1000 tons of fission products, per year. Waste disposal is a field in which ingenuity and imagination can pay off by appreciably improving the feasibility of widespread atomic power..