The impact of four electron acceptors on hydrocarbon-induced methanogenesis was studied. Methanogenesis from residual hydrocarbons may enhance the exploitation of oil reservoirs and may improve bioremediation. The conditions to drive the rate-limiting first hydrocarbon-oxidizing steps for the conversion of hydrocarbons into methanogenic substrates are crucial. Thus, the electron acceptors ferrihydrite, manganese dioxide, nitrate or sulfate were added to sediment microcosms acquired from two brackish water locations. Hexadecane, ethylbenzene or 1-(13)C-naphthalene were used as model hydrocarbons. Methane was released most rapidly from incubations amended with ferrihydrite and hexadecane. Ferrihydrite enhanced only hexadecane-dependent methanogenesis. The rates of methanogenesis were negatively affected by sulfate and nitrate at concentrations of more than 5 and 1 mM, respectively. Metal-reducing Geobacteraceae and potential sulfate reducers as well as Methanosarcina were present in situ and in vitro. Ferrihydrite addition triggered the growth of Methanosarcina-related methanogens. Additionally, methane was removed concomitantly by anaerobic methanotrophy. ANME-1 and -2 methyl coenzyme M reductase genes were detected, indicating anaerobic methanotrophy as an accompanying process [Correction added 16 December after online publication: 'methyl coenzyme A' changed to 'methyl coenzyme M' in this sentence]. The experiments presented here demonstrate the feasibility of enhancing methanogenic alkane degradation by ferrihydrite or sulfate addition in different geological settings.

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1574-6968.2010.02165.xDOI Listing

Publication Analysis

Top Keywords

electron acceptors
8
anaerobic methanotrophy
8
'methyl coenzyme
8
ferrihydrite
5
accelerated methanogenesis
4
methanogenesis aliphatic
4
aliphatic aromatic
4
hydrocarbons
4
aromatic hydrocarbons
4
hydrocarbons iron-
4

Similar Publications

Near-infrared (NIR)-triggered type-I photosensitizers are crucial to address the constraints of hypoxic tumor microenvironments in phototherapy; however, significant challenges remain. By selecting an electron-deficient unit, a matched energy gap in the upper-level state is instrumental in boosting the efficiency of intersystem crossing for the type-I electron transfer process. 2-Cyanothiazole, an electron acceptor, is covalently linked with N, N-diphenyl-4-(thiophen-2-yl)aniline to yield a multifunctional photosensitizer (TTNH) that exhibits intrinsic NIR absorbance and compatible T energy levels, facilitating both radiative and nonradiative transitions.

View Article and Find Full Text PDF

This study proposes a green and efficient atom- and step-economical method for converting hazardous CS to dithiocarbamate derivatives under visible light irradiation and catalyst-free conditions. By the construction of novel C-S and C-N bonds, a series of β-dicarbonyl compounds and amines are incorporated into the products. Under light, CS and amine first form bis(dialkylaminethiocarbonyl)disulfides, which then react with KCO-activated β-dicarbonyl compounds to form electron donor-acceptor (EDA) complexes and subsequently generate the target products.

View Article and Find Full Text PDF

Electroactive organisms contribute to metal cycling, pollutant removal, and other redox-driven environmental processes via extracellular electron transfer (EET). Unfortunately, developing genotype-phenotype relationships for electroactive organisms is challenging because EET is necessarily removed from the cell of origin. Microdroplet emulsions, which encapsulate individual cells in aqueous droplets, have been used to study a variety of extracellular phenotypes but have not been applied to investigate EET.

View Article and Find Full Text PDF

A highly electron-rich S,N heteroacene building block is developed and condensed with FIC and Cl-IC acceptors to furnish CT-F and CT-Cl, which exhibit near-infrared (NIR) absorption beyond 1000 nm. The C-shaped CT-F and CT-Cl self-assemble into a highly ordered 3D intermolecular packing network via multiple π-π interactions in the single crystal structures. The CT-F-based organic photovoltaic (OPV) achieved an impressive efficiency of 14.

View Article and Find Full Text PDF

With the rapid advancement of information technology, the need to achieve ultra-high-density data storage has become a pressing necessity. This study synthesized three hyperbranched polyimides (HBPI-TAPP, HBPI-(Zn)TAPP, and HBPI-(Cu)TAPP) by polymerizing 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (TAPP), which features a cavity for metal ion coordination, with 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), to systematically investigate the effect of metal ion species on storage performance. According to the results, memory devices based on HBPI-(Zn)TAPP exhibit volatile SRAM (static random-access memory) characteristics, whereas devices employing HBPI-TAPP and HBPI-(Cu)TAPP demonstrate non-volatile WORM (write-once, read-many) characteristics.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!