Hydrogen production through biocatalyzed electrolysis

cum laude graduation (with distinction) To replace fossil fuels, society is currently considering alternative clean fuels for transportation. Hydrogen could be such a fuel. In theory, large amounts of renewable hydrogen can be produced from organic contaminants in wastewater. During his PhD research René Rozendal has developed a new technology for this purpose: biocatalyzed electrolysis. The innovative step of biocatalyzed electrolysis is the application of electrochemically active microorganisms in combination with small input of electrical energy. Electrochemically active microorganisms are a special group of microorganisms that are able to use an electrode as electron acceptor for the oxidation of organic material. Biocatalyzed electrolysis couples this “bio-electrode” to a hydrogen generating electrode by means of a power supply. Consequently, organic contaminants in wastewater can be oxidized (i.e. the wastewater is treated), while at the same time hydrogen is generated as a valuable product. In this way biocatalyzed electrolysis can significantly increase the hydrogen yield from wastewaters compared to other technologies. Furthermore, the innovative design makes a much wider variety of wastewaters than before suitable for hydrogen production. This makes biocatalyzed electrolysis a breakthrough technology for hydrogen production from wastewater

Science Business Center: Comparison of curtain wall façades

Graduation pfoject in both architecture and building technology. Architecture: The design of a Science Business Center, a public building in Technopolis science park, near the campus of Delft university. Building technology: a comparison of two curtain wall façade systems, the unitized façade and the traditional post- and- rail façade.SADD - Ar+BT - Science Business CenterArchitecture & Building technology (combined)Architectur

Process for producing hydrogen

A process for producing hydrogen from bio-oxidisable material is disclosed herein. The process comprises the steps of - introducing the bio-oxidisable material into a reactor provided with an anode and a cathode optionally separated by a cation exchange membrane and containing anodophilic bacteria in an aqueous medium; - applying a potential between the anode and cathode 0.05 and 1.5 volt, while maintaining a pH of between 3 and 9 in the aqueous medium; - collecting hydrogen gas at the cathode. The hydrogen production process can be intermittently switched to an electric power generation stage (biofuel cell) by adding oxygen to the cathode and separating the anode and cathode spaces by means of a cation exchange membrane

Performance of single chamber biocatalyzed electrolysis with different types of ion exchange membranes

In this paper hydrogen production through biocatalyzed electrolysis was studied for the first time in a single chamber configuration. Single chamber biocatalyzed electrolysis was tested in two configurations: (i) with a cation exchange membrane (CEM) and (ii) with an anion exchange membrane (AEM). Both configurations performed comparably and produced over 0.3 m3 H2/m3 reactor liquid volume/day at 1.0 V applied voltage (overall hydrogen efficiencies around 23%). Analysis of the water that permeated through the membrane revealed that a large part of potential losses in the system were associated with a pH gradient across the membrane (CEM ¿pH=6.4; AEM ¿pH=4.4). These pH gradient associated potential losses were lower in the AEM configuration (CEM 0.38 V; AEM 0.26 V) as a result of its alternative ion transport properties. This benefit of the AEM, however, was counteracted by the higher cathode overpotentials occurring in the AEM configuration (CEM 0.12 V at 2.39 A/m2; AEM 0.27 V at 2.15 A/m2) as a result of a less effective electroless plating method for the AEM membrane electrode assembly (MEA)

Effect of the type of ion exchange membrane on performance, ion transport, and pH in biocatalyzed electrolysis of wastewater

Previous studies have shown that the application of cation exchange membranes (CEMs) in bioelectrochemical systems running on wastewater can cause operational problems. In this paper the effect of alternative types of ion exchange membrane is studied in biocatalyzed electrolysis cells. Four types of ion exchange membranes are used: (i) a CEM, (ii) an anion exchange membrane (AEM), (iii) a bipolar membrane (BPM), and (iv) a charge mosaic membrane (CMM). With respect to the electrochemical performance of the four biocatalyzed electrolysis configurations, the ion exchange membranes are rated in the order AEM > CEM > CMM > BPM. However, with respect to the transport numbers for protons and/or hydroxyl ions (t(H/OH)) and the ability to prevent pH increase in the cathode chamber, the ion exchange membranes are rated in the order BPM > AEM > CMM > CEM

Policies to Encourage the Development of Water Sanitation Technology

This chapter examines innovations in water technology, policies to develop technologies that will contribute to a sustainalbe economy, and the introduction of the new concepts to society. We discuss our views on how wastewater treatment may be performed in the future in such a way that the WFD guidelines are met economically. Preventing the mixing and diluting of different wastewater streams would enable reuse of valuable components (energie, minerals, and water). This chapter also decribes nitrogen removal and recovery techniques that can convert ammonia and nitrates into dinitrogen gas. At present, industrial ammonia synthesis from dinitrogen gas is more economically feasible than reuse of ammonia from wastewater. Chemical and biological methods to remove phosphorus are examined as well. Phosphorus is a good potential target for reuse, as the natural reserves of the ore are limited. Removal of phophorus from wastewater would also decrease eutrophication of natural water. Membrane bioreactors are very promising in the treatment of special industrial wastewater or enhanced treatment of municipal wastewater. The chapter then looks at bioelectrochemical conversion processes-microbial fuel cells and biocatalyzed electrolysis-new techniques to recover energy from wastewater that require less erngy than conventional techniques. Therefore, more energy is left in the wastewater and conversion into methane, electricity, or hydrogen becomes possibl

Towards practical implementation of bioelectrochemical wastewater treatment

Bioelectrochemical systems (BESs), such as microbial fuel cells (MFCs) and microbial electrolysis cells (MECs), are generally regarded as a promising future technology for the production of energy from organic material present in wastewaters. The current densities that can be generated with laboratory BESs now approach levels that come close to the requirements for practical applications. However, full-scale implementation of bioelectrochemical wastewater treatment is not straightforward because certain microbiological, technological and economic challenges need to be resolved that have not previously been encountered in any other wastewater treatment system. Here, we identify these challenges, provide an overview of their implications for the feasibility of bioelectrochemical wastewater treatment and explore the opportunities for future BESs

Cost effective cation exchange membranes: A review

This paper will look at developments of new polymer electrolyte membranes to replace high cost ion exchange membranes such as Nafion , Flemion and Aciplex . These perfluorinated polymer electrolytes are currently the most commercially utilized electrolyte membranes for polymer electrolyte fuel cells, with high chemical stability, proton conductivity and strong mechanical properties. While perfluorinated polymer electrolytes have satisfactory properties for fuel cell applications, they limit commercial use due to significant high costs as well as reduced performance at high temperatures and low humidity. A promising alternative to obtain high performance proton-conducting polymer electrolyte membranes is through the use of hydrocarbon polymers. The need for inexpensive and efficient materials with high thermal and chemical stability, high ionic conductivity, miscibility with other polymers, and good mechanical strength is reviewed in this paper. Though it is difficult to evaluate the true cost of a product based on preliminary research, this paper will examine several of the more promising materials available as low cost alternatives to ion exchange membranes. These alternative membranes represent a new generation of cost effective electrolytes that can be used in various ion exchange systems. This review will cover recent and significant patents regarding low cost polymer electrolytes suitable for ion exchange membrane applications. Promising candidates for commercial applications will be discussed and the future prospects of cost effective membranes will be presented