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A Novel Catalyst for Aqueous Chlorate Reduction with High Activity, Salt Resistance, and Stability

Prof. Jinyong Liu’s lab at UCR has developed a novel heterogeneous catalyst for aqueous ClO3− reduction. The catalyst contains earth-abundant molybdenum (Mo) and is 55-fold more active than palladium on carbon (Pd/C). Under 1 atm H2 and room temperature, the bimetallic catalyst (MoOx−Pd/C) enables rapid and complete reduction of ClO3− in a wide concentration range (e.g., 1 μM to 1 M) and exhibits strong resistance to concentrate salts such as chloride, sulfate, and bromide at 1 to 5 M. In a batch reactor setup, the catalyst was reused for twenty cycles of 0.18 M ClO3− reduction and no activity loss was observed. Fig. 1 shows the effect of concentrated salts on the reduction of 1 mM ClO3− by the MoOx-Pd/C catalyst at a loading of 0.2 g/L. The reactions were conducted at 25 oC and under 1 atm H2. Fig. 2 shows the reduction of 1 M ClO3− in DI water and the treatment of a synthetic chlor-alkali waste brine sample (0.17 M of ClO3− in 3.6 M of NaCl) by 0.5 g/L MoOx-Pd/C.   Fig. 3 shows the profiles of the reduction of 0.18M ClO3− spikes in a multiple-spike reaction series. The decrease of activity was only caused by the gradual build-up of concentrated Cl− (see details in the publication).  

New Catalysts for Perchlorate Reduction in Water

Prof. Jinyong Liu’s lab at UCR has developed a new family of catalysts that reduce perchlorate in contaminated water and wastewater. The catalyst rapidly and completely reduces the toxic ClO4- into the innocuous chloride (Cl -) by breaking down the bonds between the central chlorine atom and all surrounding oxygen atoms. The reduction is a green process because no byproducts are produced in the water. The catalyst completely reduces perchlorate in a very wide concentration range, and retains high activity even in brine with concentrated salts. The catalyst using earth-abundant and non-toxic metal provides sustainable solutions to the perchlorate issues in terms of water and wastewater treatment, ion-exchange resin regeneration, and old munition/explosive disposal. Not only can this new catalyst reduce perchlorate but it may also be used to reduce other drinking water contaminants such as chlorate, chlorite, nitrate, nitrite, bromate, and iodate in a variety of environmental remediation scenarios.  Fig. 1 shows the reduction profiles of 1, 10, and 100 mM ClO4− (corresponding to 100,000 to 10,000,000 ppb) by the UCR catalyst at a loading of only 0.2 g/L. The reactions were conducted at 25 oC and under 1 atm H2. Fig. 2 shows the high activity for the catalytic reduction of 1 mM ClO4− by the UCR catalyst (just 0.2 g/L) in the typical resin generation wastes containing chloride and sulfate.

Buffer-Free Process Cycle For Co2 Sequestration And Carbonate Production From Brine Waste Streams With High Salinity

Researchers in the UCLA Department of Civil and Environmental Engineering have developed a novel process cycle to separate and enrich divalent cations such Ca2+ and Mg2+ from high salinity brine solutions for CO2 mineralization.

Anti-Fouling And Self-Cleaning Electrically Conducting Low-Pressure Membranes For Water Treatment

Researchers in the UCLA Department of Civil and Environmental Engineering have developed anti-fouling and self-cleaning membranes for use in municipal and industrial wastewater treatment, with particular applications for anaerobic membrane bioreactors.

System and Method for Flexible Low-Energy Membrane-Based Liquid Purification

UCLA researchers in the Department of Chemical and Biomolecular Engineering have developed a platform and method for membrane-based water purification and desalination that combines operational flexibility with energy efficiency, allowing effective treatment and desalination of raw feed water over a wider range of solute concentrations and product recovery.

Optimizing A Mixed Microbial Community For Biodegradation Of Halogenated Solvents And 1,4-Dioxane

UCLA researchers in the Department of Civil and Environmental Engineering have formulated a microbial community that degrades halogenated solvents and their stabilizers in water resources.

Hydrocarbon Production, H2 Evolution And CO2 Conversion By Whole Cells Or Engineered Azotobacter Vinelandii Strains

Using metal catalysts in industrial synthesis of hydrocarbons for fuels can be costly, inefficient, and harmful to the environment. This simple approach uses genetically-modified soil bacterium to synthesize valuable hydrocarbons using recycled components. This novel process is environmentally-friendly and is more cost- and energy-efficient than current industrial synthesis.

Biomass-Derived Polymers And Copolymers Incorporating Monolignols And Their Derivatives

UCLA researchers in the Departments of Bioengineering, Chemistry and Biochemistry have developed a novel synthetic strategy for the fabrication of biomass-derived polymers incorporating underutilized lignin derivatives.

New Strategy for Biofilm Control

Biofilms are a pervasive problem across numerous global industries, including oil & gas production and healthcare. Microbes have spent millennia learning how to survive, and society remains in critical need of effective strategies to remove them without harsh or damaging processes. Microbial biofouling currently costs tens of billions of dollars a year to deal with, from fouling of filtration membranes, to the corrosion of ship hulls. New biofilm clearance strategies are now required, to harness microbiological understanding to efficiently eradicate microbial contamination.

Methods for Fabrication of Electric Propulsion Tips

The technology is a method for fabrication of silicon microfabricated emitter tips.This process has two-step etching process which utilizes field emission electric propulsion (FEEP) and indium propellant.

Carbon Sequestration Using a Magnetic Treatment System

The technology is a technique for the capture and removal of carbonates in natural water sources.It features the use of an alternating electromagnetic field (AMF) to induce the formation of calcium carbonate or other carbonate compounds in suspension in water source. Additionally, carbonate compounds are removed using filtration device.

Multi-Dimensional Networks

Brief description not available

Palladium Alloy Hydride Nano Materials

Researchers at UCLA have synthesized a range of intermetallic palladium hydride alloy (Pd/M-H) nanocrystals using a low cost solution process that avoids the use of surfactants and strong reducing agents.

CeramicAsh: Material and Method

Researchers at UCLA have developed a method for reducing the manufacturing costs associated with chemically bonded ceramics. 

Bulking And Foaming Filamentous Bacteria Nucleic Acid Sequences For Multiple Simultaneously Identifications

Researchers in UCI’s Department of Environmental & Civil Engineering have developed a revolutionary solution to the problem bulking and foaming organisms found in wastewater treatment systems. Their kit provides a fast, accurate and extremely cost effective method of identifying these troublesome organisms to allow rapid treatment prior to the onset of costly post “bloom” remediation.

Recombinant Cell Bioassay For Rapid Detection Of Androgenic And Antiandrogenic Chemicals

Increasing exposure of humans and animals to environmental endocrine disruptors is of great concern.  Therefore, there is need for rapid and effective detecting systems for endocrine disruptors in environmental and biological samples.  However, it is problematic that the current detecting systems cannot detect new chemicals that can act like testosterone (and other androgenic) or antiandrogenic chemicals, because these chemicals can be structurally diverse.  A researcher at the University of California, Davis developed a novel, cell-based bioassay that detects diverse compounds, known and new, that impact the androgen receptor signaling pathway.

Hybrid Extraction Process For Separation Of Americium From Trivalent Lantanides

Researchers in UCI’s Department of Chemical Engineering/Material Science have developed a process to separate americium (Am) from trivalent lanthanides, both present in spent nuclear fuel. This separation is necessary for future nuclear fuel cycles.

Monoclonal Antibodies And Immunoassay Specific For The Toxic Congeners Of Polychlorinated Biphenyls

Polychlorinated biphenyls (PCBs) are ubiquitous environmental pollutants with diverse toxic, teratogenic, reproductive, immunotoxic, and tumorigenic effects. Three of the least abundant of the 209 PCB isomers (congeners) are the most toxic and most difficult to quantify. These are 3,4,3',4'-tetrachlorobiphenyl, 3,4,3',4',5'-pentachlorobiphenyl, and 3,4,5,3',4',5'-hexachlorobiphenyl (IU-PAC No. 77, 126, and 169, respectively). An immunizing hapten was designed to retain the 3,4,3',4' chlorine-substitution pattern and coplanarity characteristic of these toxic congeners. The optimal competitors for immunoassay were weaker binding distinctive single-ring fragments of the PCBs. A monoclonal antibody designated S2B1 was derived and used in direct (antibody-capture) competitive enzyme immunoassays (EIAs). The EIAs are highly specific for non-ortho-substituted congeners and do not recognize the more prevalent but much less toxic noncoplanar PCB congeners or 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, or dichlorobenzenes. Hapten and competitor design for this assay suggests a basis for development of sensitive EIAs for other classes of PCB congeners. Reference: Chiu, YW, et al. 1995 Anal Chem. 67::3829-39

Detecting Arsenic In Groundwater Using Nanostructures

The presence of Arsenic (As) in groundwater, even at low levels, is a significant public health problem -- especially in economically undeveloped regions. However, methods for detecting this toxin in groundwater are problematic because they are not sensitive enough to detect low levels of As, not conducive to fast in-field detection, and/or cost-prohibitive (particularly for poor regions). To address this international problem, researchers at UC Berkeley have developed an improved method for detecting As in groundwater as low as 1.8 parts per billion. This new sensor method is based on surface-enhanced Raman spectroscopy (SERS), in which analyte molecules near nanostructured metallic surfaces exhibit huge enhancements in Raman scattering. The Berkeley approach is a refinement of this SERS technology. Whereas previous attempts to use SERS to detect As have reported low sensitivities and poor signal-to-noise rations, this novel SERS-based approach achieved toxin detection levels of parts per billion. In addition to being highly sensitive, this innovative approach is portable, disposable, easily prepared and readily can be used for in-field applications. The sensor also has the unique ability to distinguish between the As(V) and As(III) ionic species.

Improved Nanocomposite Membranes For Fuel Cells And Air Separations

The physical properties of polymer membranes pose severe limits on performance when used in applications such as fuel cells and air separation modules. In the case of proton-exchange membranes (PEMs) used in fuel cells such as Nafion®, temperatures must be kept below 80°C in order to keep polyfluorocarbon membranes sufficiently hydrated for proton conduction, but the performance of fuel cell electrodes will be improved if the operational temperatures is increased to above 100°C. In fuel cells that derive protons from liquid hydrocarbon such as direct methanol fuel cells (DMFCs), there is an additional problem of performance being further degraded by PEM permeability to methanol (“methanol crossover”). In the case of air separation modules, polymer membranes suffer from low O2/N2 selectivity (~6). Modestly higher selectivities can be achieved by adding silica particles to the polymer (up to ~9), but selectivities need to be at least 30 for membranes tightly-packed into compact modules to provide efficient oxygen enrichment. The highly selective materials that have been tried so far, such as carbon molecular sieves and zeolite membranes, are too fragile and expensive for practical use as substitutes for fluorocarbon polymer membranes in air separation modules.

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