Mixed-culture biocathodes for acetate production from CO reduction in the microbial electrosynthesis: Impact of temperature.

The temperature effect on bioelectrochemical reduction of CO to acetate with a mixed-culture biocathode in the microbial electrosynthesis was explored. The results showed that maximum acetate amount of 525.84 ± 1.

Bioelectrochemical decolorization of a reactive diazo dye: Kinetics, optimization with a response surface methodology, and proposed degradation pathway.

Bioelectrochemical systems (BESs) have shown great potential for azo dye removal. However, comprehensive evaluation of the bioelectrochemical decolorization performance for reactive diazo dyes remains limited, particularly the kinetics and operation parameter optimization. This study evaluated the decolorization of the diazo dye Reactive Black 5 (RB5) in BESs, particularly with regard to kinetics, parameter optimization using response surface methodology (RSM), and the degradation pathway.

Effect of surface modification on carbon nanotubes (CNTs) catalyzed nitrobenzene reduction by sulfide.

Carbon nanotubes (CNTs) could be directly used as metal-free catalysts for the reduction of nitroaromatics by sulfide in water, but their catalytic ability need a further improvement. This study evaluated the feasibility of surface modification through thermal and radiation pretreatments to enhance catalytic activity of CNTs on nitrobenzene reduction by sulfide. The results show that thermal treatment could effectively improve the catalytic behaviors of CNTs for the reduction of nitrobenzene by sulfide, where the optimum annealing temperature was 400 °C.

A modified two-point titration method for the determination of volatile fatty acids in anaerobic systems.

The volatile fatty acids (VFA) concentration plays important roles in the rapid start-up and stable operation of anaerobic reactors. It's essential to develop a simple and accurate method to monitor the VFA concentration in the anaerobic systems. In present work, a modified two-point titration method was developed to determine the VFA concentration.

Temperature dependence of bioelectrochemical CO conversion and methane production with a mixed-culture biocathode.

This study evaluated the effect of temperature on methane production by CO reduction during microbial electrosynthesis (MES) with a mixed-culture biocathode. Reactor performance, in terms of the amount and rate of methane production, current density, and coulombic efficiency, was compared at different temperatures. The microbial properties of the biocathode at each temperature were also analyzed by 16S rRNA gene sequencing.

Impact of zero-valent iron nanoparticles on the activity of anaerobic granular sludge: From macroscopic to microcosmic investigation.

The study aimed at evaluating the influence of nano zero-valent iron (nZVI) on the activity of anaerobic granular sludge (AGS) from both macroscopic and microcosmic aspects using different methodologies. The tolerance response of AGS to nZVI was firstly investigated using short-term and long-term experiments, and also compared with anaerobic flocs. The Fe fate and distribution, the change of contents/structure of extracellular polymeric substances (EPS), and the variation of microbial community in the AGS after exposure to nZVI were further explored.

Facilitated biological reduction of nitroaromatic compounds by reduced graphene oxide and the role of its surface characteristics.

How reduced graphene oxide (RGO) mediates the reductive transformation of nitroaromatic pollutants by mixed cultures and the role of its surface characteristics were evaluated in this study. Different electron donors were applied to investigate the interaction between RGO and anaerobic microbes. Moreover, the influence of the surface properties of RGO on biological nitroaromatic removal was further elucidated.

Process and kinetics of azo dye decolourization in bioelectrochemical systems: effect of several key factors.

This study explored the influence of several key factors on the process and kinetics of azo dye decolourization in bioelectrochemical systems (BESs), including cathode potential, dissolved oxygen (DO) concentration of catholyte and biofilm formed on the cathode. The results show that azo dye methyl orange (MO) decolourization in the BES could be well described with the pseudo first-order kinetics. The MO decolourization efficiency increased from 0 to 94.

Enhancement of azo dye decolourization in a MFC-MEC coupled system.

Microbial fuel cells (MFCs) have shown the potential for azo dye decolourization. In this study, a MFC-MEC (microbial electrolysis cell) coupled system was established in order to enhance azo dye decolourization, and the influence of several key factors on reactor performance was evaluated. Moreover, a theoretical analysis was conducted to find the essential preconditions for successfully develop this MFC-MEC coupled system.

Hydrodynamics of an electrochemical membrane bioreactor.

An electrochemical membrane bioreactor (EMBR) has recently been developed for energy recovery and wastewater treatment. The hydrodynamics of the EMBR would significantly affect the mass transfers and reaction kinetics, exerting a pronounced effect on reactor performance. However, only scarce information is available to date.

Electron acceptors for energy generation in microbial fuel cells fed with wastewaters: A mini-review.

Microbial fuel cells (MFCs) have gained tremendous global interest over the last decades as a device that uses bacteria to oxidize organic and inorganic matters in the anode with bioelectricity generation and even for purpose of bioremediation. However, this prospective technology has not yet been carried out in field in particular because of its low power yields and target compounds removal which can be largely influenced by electron acceptors contributing to overcome the potential losses existing on the cathode. This mini review summarizes various electron acceptors used in recent years in the categories of inorganic and organic compounds, identifies their merits and drawbacks, and compares their influences on performance of MFCs, as well as briefly discusses possible future research directions particularly from cathode aspect.

The maximum specific hydrogen-producing activity of anaerobic mixed cultures: definition and determination.

Fermentative hydrogen production from wastes has many advantages compared to various chemical methods. Methodology for characterizing the hydrogen-producing activity of anaerobic mixed cultures is essential for monitoring reactor operation in fermentative hydrogen production, however there is lack of such kind of standardized methodologies. In the present study, a new index, i.