We provide methods, systems, and apparatus for treatment of high chemical oxygen demand wastewater using anaerobic treatment with ceramic membranes. We also provide post-treatment using microbial fuel cells.

Bacteria-based catalysts including a bacterium and one or more metal oxides are disclosed. The metal oxides are dispersed on the surface of the bacterium. The bacterium can be an electrogenic bacterium, which employs an extracellular electron transport pathway to transfer metabolically generated electrons to cell-exterior. The bacteria-based catalysts can be made by: (a) oxidizing a substrate molecule by a bacterium to generate electrons; (b) transporting the electrons to one or more metal oxide precursors; and (c) reducing the metal oxide precursors to metal oxides. The bacteria-based catalysts disclosed herein can be used in electrocatalysis, photocatalysis, or chemical catalysis. For example, they can catalyze oxygen evolution reaction (OER) and outperform commercial metal oxide catalyst for OER with superior operational stability.

Systems and methods for treating a metal or metalloid ion-contaminated liquid are provided. The method may include (i) feeding the metal or metalloid ion-contaminated liquid into a bioelectrochemical reactor containing a bacteria selected by the cathode to produce extracellular metal or metalloid nanoparticles; and (ii) operating the bioelectrochemical reactor anaerobically to reduce the metal or metalloid ions in the metal or metalloid ion-contaminated liquid to extracellular metal or metalloid nanoparticles. The method may further include separating the metal or metalloid nanoparticles from the bacteria with no energy input. A bioelectrochemical reactor system for production of extracellular metal and metalloid nanoparticles may include a bioelectrochemical reactor, a separation device, and a tangential flow filtration unit.

A technique for wastewater treatment involves ensuring that all paths for wastewater must pass through at least one porous microbial support to go from the inlet to the outlet, and allowing a biofilm to grow on the porous microbial support under microaerobic conditions (concentration of oxygen between 0.05 and 0.35 mg/L). The biofilm formed comprises a population of anaerobic microbes for digesting organics in the wastewater including methanogenic microbes, and an aerobic methanotrophic and heterotrophic population that catabolizes methane from the methanogenic microbes, and oxygen from the injector, to produce heat. The support may be an electrode, and the technique is applied in a microbial electrolysis cell, with substantial COD removal rates.

A method for changing filler pollutant accumulation of a constructed wetland belongs to the field of environmental protection engineering. A coupling device of a microbial fuel cell and a constructed wetland is constructed by using active carbon as a constructed wetland filler, and pond sewage enters into the constructed wetland from the top of the device in an intermittent mode. A titanium mesh is taken as an electron collector for packaging a cathode of the active carbon filler by using the characteristic that electrons are collected by the titanium mesh in a concentrated mode, after stable operation for a period of time, active carbon close to a water surface and active carbon close to the bottom of the titanium mesh are taken out for carrying out specific surface area and biomass measurement, and the accumulation distribution condition of filler pollutants inside the constructed wetland is analyzed.

Method of desalination and wastewater treatment in a microbial desalination cell reactor is provided, the microbial desalination cell reactor has three compartments, an anodic compartment, a cathodic compartment and a saline compartment, the method is carried out by (a) adding electrically conductive particles or electrically conductive material in the anodic compartment and cathodic compartment, (b) adding bacteria species of the genus Geobacter in the anodic compartment and several solutions in the compartments (c) replacing the solutions in the cathodic compartment and in the saline compartment and (d) oxidizing organic matter present in wastewater by bacteria from the genus Geobacter in the anodic compartment and desalinating the solution in the saline compartment and (e)after 20 to 30 operation cycles, replacing the solution in the saline compartment by a solution of hypochlorite salt.

A sewage/wastewater biological treatment systemsewage (wastewater) synergistic treatment acceleration device, which includes four components of a reaction assembly, a signal transmission assembly, a control assembly, and a housing carrying assembly. The reaction assembly can realize the colonization/proliferation of functional microorganisms, participate in the interface electron transfer between the electrode-microbe-sewage as an electron donor/receptor and electrode interface of the (bio)electrochemical reaction, and optimize the flow characteristics in the sewage/wastewater treatment system. The signal transmission assembly enables the conduction of applied voltage and real-time signal acquisition and transmission of key parameters. The monitoring assembly implements intelligent controllability of the present invention. The housing carrying assembly enables integrated assembly of single device and multi-device serial/parallel operation assembly.

Methods of making improved bioelectrodes are provided capable of functionalizing electrode materials in less than 24 hours. Pre-seeding the electrode with electricigenic microbes forms an electricigenic biofilm on the electrode to maximize surface coverage by electricigenic microbes and reduce the number of fastidious organisms. The method results in bioelectrodes that are functionalized in less than 24 hours and that can generate higher yields of current from a wide range of substrates. Methods for treating wastewater by removing fermentative inhibitors and generating current are provided. The bioelectrodes generated are tailored to efficiently oxidize substrates, such as the fermentative inhibitors, in the wastewater targeted for removal from the wastewater. Improved electrodes are generated rapidly with high coulombic efficiency. Bioelectrochemical systems (BESs) containing the improved electrodes are also provided.

A reactor for water splitting or water treatment includes a first electrode, a second electrode electrically coupled to the first electrode, and a proton exchange membrane separating the first electrode and the second electrode. The first electrode includes a first optical fiber coated with a photocatalytic material.

The present disclosure relates to a sensor for monitoring metabolic activity of a population of exo-electrogenic bacteria in response to one or more agents in oxygenated water or wastewater in a water or wastewater treatment system. The sensor comprises: at least one electrode pair comprising an anode and a cathode, the anode in electrical communication with the exo-electrogenic bacteria for receiving electrons therefrom; a current sensor for measuring electron flow between the anode and the cathode and producing an electrical output that correlates with metabolic activity of the exo-electrogenic bacteria; and a power source in electrical communication with the electrode pair for delivering a voltage across the electrode pair. A method, system, and exo-electrogenic bacteria used for monitoring and/or controlling one or more agents in oxygenated water or wastewater is also provided.