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Bradley P. Ladewig

Bio: Bradley P. Ladewig is an academic researcher from Karlsruhe Institute of Technology. The author has contributed to research in topics: Membrane & Adsorption. The author has an hindex of 36, co-authored 96 publications receiving 4126 citations. Previous affiliations of Bradley P. Ladewig include Australian Nuclear Science and Technology Organisation & Imperial College London.


Papers
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TL;DR: This paper reviews membrane fouling types and fouling control strategies, with a focus on the latest developments, including biofouling, organic fouling, inorganic scaling and colloidal fouling.

567 citations

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TL;DR: For post-combustion carbon dioxide capture technology to realize widespread viability, the energy costs must be drastically reduced, and adsorbent candidates are metal–organic frameworks (MOFs), because of their large adsorption capacities, and the potential for incorporation of light-responsive organic groups within the pore structure.
Abstract: For post-combustion carbon dioxide capture technology to realize widespread viability, the energy costs must be drastically reduced. Current adsorbent technologies that rely on pressure, temperature, or vacuum swings consume as much as 40% of the production capacity of a power plant, most of which is associated with the liberation of CO2 from the capture medium. Ultimately this penalty, or parasitic energy load, must be brought closer to the thermodynamic minimum of about 4% to avoid prohibitive cost increases. Given that the triggers for release of adsorbed carbon dioxide, such as vacuum and heating, are so energy intensive, 3] requiring energy from the power plant, there is strong motivation to develop new release triggers that do not require extra energy from the plant, using renewable energy sources such as the sun. In conjunction with this, adsorbents with maximum gas sorption efficiency can further reduce the costs compared to the conventional energy-intensive CO2 gas separation process. Light, and in particular concentrated sunlight, is an extremely attractive stimulus for triggering CO2 release. If used with an adsorbent material that strongly absorbs sunlight concomitant with the desorption of large amounts of CO2, it may be possible to drastically reduce the energy costs. Perhaps the most attractive adsorbent candidates are metal–organic frameworks (MOFs), because of their large adsorption capacities, and the potential for incorporation of light-responsive organic groups within the pore structure. MOFs are an important class of 3D crystalline porous materials comprised of metal centers and organic ligands, joined periodically to establish a crystalline porous array. The large internal surface areas can be used to adsorb unprecedented quantities of gases, with particular interest in hydrogen, methane, 8] and carbon dioxide emergent. 7b,h,9] Methods for the incorporation of light-responsive groups within MOFs include the use of pendant groups pointing into the pores, and filling of pores with light-responsive guest molecules. The responsive groups within these materials may then alter their conformation when exposed to filtered light which results in a change in adsorption capacity, as reported thus far for static conditions. The responsive groups within these MOFs can be statically set to one position or another. For use in photoswing carbon dioxide capture, MOFs that can respond dynamically, or to the broadband radiation found in sunlight whilst loaded with adsorbed gas, are ideal. This will increase the speed of operation and lower the energy costs (see Figure 1)

287 citations

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TL;DR: In this paper, mesoporous silica (MS) particles were synthesized as inorganic fillers, and fabricated with polyethersulfone (PES) to achieve nanocomposite membranes with antifouling properties by phase inversion method.

248 citations

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TL;DR: In this paper, the authors highlight advancements made in anion exchange membrane (AEM) head groups, polymer structures and membrane synthesis methods, and discuss limitations of current analytical techniques for characterizing AEMs.
Abstract: This review highlights advancements made in anion exchange membrane (AEM) head groups, polymer structures and membrane synthesis methods. Limitations of current analytical techniques for characterizing AEMs are also discussed. AEM research is primarily driven by the need to develop suitable AEMs for the high-pH and high-temperature environments in anion exchange membrane fuel cells and anion exchange membrane water electrolysis applications. AEM head groups can be broadly classified as nitrogen based (e.g. quaternary ammonium), nitrogen free (e.g. phosphonium) and metal cations (e.g. ruthenium). Metal cation head groups show great promise for AEM due to their high stability and high valency. Through “rational polymer architecture”, it is possible to synthesize AEMs with ion channels and improved chemical stability. Heterogeneous membranes using porous supports or inorganic nanoparticles show great promise due to the ability to tune membrane characteristics based on the ratio of polymer to porous support or nanoparticles. Future research should investigate consolidating advancements in AEM head groups with an optimized polymer structure in heterogeneous membranes to bring together the valuable characteristics gained from using head groups with improved chemical stability, with the benefits of a polymer structure with ion channels and improved membrane properties from using a porous support or nanoparticles.

197 citations

Journal ArticleDOI
TL;DR: In this article, the intrinsic gas permeability and separation properties of several new Zeolitic Imidazolate Frameworks (ZIFs), a family of the Metal-Organic Frameworks, were predicted using a molecular simulation approach, Monte Carlo procedures, free volume analysis, and continuum modeling.
Abstract: Gas separation technologies for carbon-free hydrogen and clean gaseous fuel production must efficiently perform the following separations: (1) H2/CO2 (and H2/N2) for pre-combustion coal gasification, (2) CO2/N2 for post-combustion of coal, (3) CO2/CH4 for natural gas sweetening and biofuel purification, and (4) O2/N2 for oxy-combustion of coal. By utilizing a molecular simulation approach, Monte Carlo procedures, free volume analysis, and continuum modeling, we predict the intrinsic gas permeability and separation properties of several new Zeolitic Imidazolate Frameworks (ZIFs), a family of the Metal–Organic Frameworks (MOFs). The well defined pore sizes in conjunction with high surface areas make ZIFs prime candidates for molecular sieving. In this work, our calculated intrinsic properties are compared with current experimental results where ZIFs are either grown in dense layers to form pure inorganic membranes on porous supports or dispersed within a polymer phase to form mixed matrix membranes. Consequently, this paper assesses current membrane development according to industrial feasibility targets and highlights the achievable superior separation results for ideal membrane configurations. For example, ZIF-11 is discovered to be capable of sieving H2 from all of its larger gas counterparts at a remarkable H2/CO2 selectivity of 262 and H2 permeability of 5830 Barrer, well within the target area for efficient hydrogen production.

155 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, the authors present the latest status of PEM fuel cell technology development and applications in the transportation, stationary, and portable/micro power generation sectors through an overview of the state-of-the-art and most recent technical progress.

2,687 citations

Journal ArticleDOI
TL;DR: In this article, the authors present an overview of the key requirements for the proton exchange membranes (PEM) used in fuel cell applications, along with a description of the membrane materials currently being used and their ability to meet these requirements.

1,715 citations

Journal ArticleDOI
TL;DR: Advances in flexible and functional metal-organic frameworks (MOFs), also called soft porous crystals, are reviewed by covering the literature of the five years period 2009-2013 with reference to the early pertinent work since the late 1990s.
Abstract: Advances in flexible and functional metal–organic frameworks (MOFs), also called soft porous crystals, are reviewed by covering the literature of the five years period 2009–2013 with reference to the early pertinent work since the late 1990s. Flexible MOFs combine the crystalline order of the underlying coordination network with cooperative structural transformability. These materials can respond to physical and chemical stimuli of various kinds in a tunable fashion by molecular design, which does not exist for other known solid-state materials. Among the fascinating properties are so-called breathing and swelling phenomena as a function of host–guest interactions. Phase transitions are triggered by guest adsorption/desorption, photochemical, thermal, and mechanical stimuli. Other important flexible properties of MOFs, such as linker rotation and sub-net sliding, which are not necessarily accompanied by crystallographic phase transitions, are briefly mentioned as well. Emphasis is given on reviewing the recent progress in application of in situ characterization techniques and the results of theoretical approaches to characterize and understand the breathing mechanisms and phase transitions. The flexible MOF systems, which are discussed, are categorized by the type of metal-nodes involved and how their coordination chemistry with the linker molecules controls the framework dynamics. Aspects of tailoring the flexible and responsive properties by the mixed component solid-solution concept are included, and as well examples of possible applications of flexible metal–organic frameworks for separation, catalysis, sensing, and biomedicine.

1,560 citations

Journal ArticleDOI
TL;DR: This review provides a comprehensive account of significant progress in the design and synthesis of MOF-based materials, including MOFs, MOF composites and MOF derivatives, and their application to carbon capture and conversion.
Abstract: Rapidly increasing atmospheric CO2 concentrations threaten human society, the natural environment, and the synergy between the two. In order to ameliorate the CO2 problem, carbon capture and conversion techniques have been proposed. Metal–organic framework (MOF)-based materials, a relatively new class of porous materials with unique structural features, high surface areas, chemical tunability and stability, have been extensively studied with respect to their applicability to such techniques. Recently, it has become apparent that the CO2 capture capabilities of MOF-based materials significantly boost their potential toward CO2 conversion. Furthermore, MOF-based materials’ well-defined structures greatly facilitate the understanding of structure–property relationships and their roles in CO2 capture and conversion. In this review, we provide a comprehensive account of significant progress in the design and synthesis of MOF-based materials, including MOFs, MOF composites and MOF derivatives, and their application to carbon capture and conversion. Special emphases on the relationships between CO2 capture capacities of MOF-based materials and their catalytic CO2 conversion performances are discussed.

1,378 citations