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News Article | November 14, 2016
Site: www.eurekalert.org

Dr. Israel E. Wachs, the G. Whitney Snyder Professor of Chemical and Biomolecular Engineering at Lehigh University, has been named as recipient of the AIChE's top award in chemical reaction engineering. Wachs will be formally recognized with the R. H. Wilhelm Award at the 2016 AIChE Annual Meeting, November 13-18 in San Francisco, CA. AIChE is the world's leading organization for chemical engineering professionals, with more than 50,000 members from over 100 countries. Its Annual Meeting is the premier forum for chemical engineers interested in cutting edge research, new technologies, and emerging growth areas in chemical engineering. The director of Lehigh's Operando Molecular Spectroscopy and Catalysis Laboratory, Wachs' contributions over three decades have been integral to the development of cutting edge research, new technologies and emerging growth areas in chemical reaction engineering. "There can be nothing more central to our profession than reaction engineering," says Mayuresh Kothare, chair of chemical and biomolecular engineering at Lehigh. "Winning the Wilhelm Award is, therefore, a very special moment for our department, and a fitting way to celebrate Israel's 30 years of pioneering accomplishments in this core area of our discipline." In particular, Dr. Wachs was recognized for "seminal contributions towards development of innovative concepts for molecular chemical reaction engineering of mixed oxide catalyzed reactions by establishing fundamental catalyst molecular structure-activity kinetic relationships." In one project, Wachs leads a team of researchers from Lehigh and the Stevens Institute of Technology that recently announced major advances in the fundamental understanding of a catalytic reaction that directly converts natural gas into valuable liquid fuels (gasoline, diesel and jet fuel). Natural gas, the researchers say, is abundant and inexpensive--but terribly underutilized. More than half the world's known reserves are classified as stranded due to high cost of transport or lack of efficient remote processing technologies. Moreover, when an oil well is drilled, natural gas is often flared--burned off--or vented into the atmosphere, where it contributes significantly to global warming. Worldwide, more than 140 billion cubic meters of natural gas are flared or vented every year due to this practice, roughly equivalent to 20% of all the natural gas consumed annually in the United States. And methane, the main component of natural gas, traps about 86 times more heat over a 20-year period than carbon dioxide. To leverage 'stranded' gas while protecting the environment, new technologies for natural gas conversion are under development. Wachs' team explores the direct conversion of natural gas into liquid aromatic hydrocarbons in a single step without oxidizing reagents. This 'dehydroaromatization' of methane is achieved using catalysts with molybdenum nanostructures supported on shape-selective zeolites. This technology, say the researchers, offers unique advantages over other methane activation chemistries because it does not require the transportation of reagents to remote locations. The Lehigh-Stevens team believes their published results could help overcome one of the biggest technical obstacles--the rapid deactivation of the molybdenum catalyst. The new technologies will address not only the economic issue of natural gas conversion into liquid fuels and chemical feedstocks but also a significant environmental issue. If the current venting and flaring of natural gas can be eliminated, such a reduction in greenhouse gas emissions will by itself more than meet the requirements of the Kyoto Protocol in the United Nations Framework Convention on Climate Change for all the participating countries combined. Dr. Wachs' research focuses on the catalysis science of mixed metal oxides (supported metal oxides , bulk metal oxides, polyoxometalates, zeolites and molecular sieves) for numerous catalytic applications (selective oxidation for manufacture of value-added chemicals, environmental catalysis (selective catalytic reduction of NOx and SOx), hydrocarbon conversion by solid acid catalysts for increased fuel energy content, olefin metathesis for on demand production of scarce propylene, olefin polymerization, conversion of methane to liquid aromatic fuels, oxidative coupling of methane to ethylene (the most important intermediate for the chemical industry), biomass pyrolysis for production of liquid fuels, conversion of bioethanol to butadiene for manufacture of green tires (biomass-to-tires), water-gas shift for production of hydrogen and photocatalytic splitting of water for clean hydrogen. His research aims to identify the catalytic active sites present on the heterogeneous catalyst surface to allow establishment of fundamental structure-activity/selectivity relationships that will guide the rational design of advanced catalysts. The research approach taken by the Wachs group is to simultaneously monitor the surface of the catalyst with spectroscopy under reaction conditions and online analysis of reactant conversion and product selectivity with online GC/mass spectrometer analysis. This new methodology has been termed operando spectroscopy and is allowing for the unprecedented development of molecular level structure-activity/selectivity relationships for catalysts. The spectroscopic techniques employed by the Wachs group for determination of the catalytic active sites and surface reaction intermediates are Raman, infrared (IR), ultraviolet- visible (UV-vis), X-ray Absorption Spectroscopy (XANES/EXAFS), Nuclear Magnetic Resonance (NMR), Electron Paramagnetic Resonance (EPR) and Temperature Programmed Surface Reaction (TPSR). Isotopic labeling of Deuterium (heavy Hydrogen-2), Oxygen-18, Nitrogen-15 and Carbon-13 is also used to track reaction pathways, ascertain rate-determining-steps, and distinguish between spectator species and actual surface reaction intermediates. The U.S. Environmental Protection Agency has previously honored Wachs with a Clean Air Excellence Award for his catalytic process that converts paper-mill pollutants into a usable, valuable product--formaldehyde--for manufacture of resins used in particle board. The American Chemical Society (ACS) has granted Wachs its George A. Olah Award for achievements in hydrocarbon and petroleum chemistry, and the American Institute of Chemical Engineering (AIChE) has previously honored Wachs with the Catalysis and Reaction Engineering Division Practice Award. He is also recipient of multiple awards from local catalysis societies in Michigan, New York, Chicago and Philadelphia. In 2011, he was named a Fellow of the American Chemical Society (ACS), the highest honor bestowed by the society. In 2012, he was recognized with a Humboldt Research Award from the Alexander von Humbolt Foundation of Germany, and the Vanadis Award from the International Vanadium Chemistry Organization. Wachs has published more than 300 highly cited technical articles (H index of >90) and holds more than three dozen patents.


Carbon dioxide can be a valuable resource for industry. It can, for example, be used as a fertilizer in greenhouses to improve plant growth. But for reasons of climate protection, it would be problematic to produce CO2 for this purpose, using fossil fuels. Filtering CO2 out of the exhaust gases from industrial processes and turning it into something useful would be much more environmentally friendly. TU Wien is working with the University of Natural Resources and Life Sciences, Shell and other partners to develop a new kind of carbon-dioxide separation technique that is both cost and energy efficient. First separation tests in the laboratories at TU Wien have already proven that the technique works. Within the "ViennaGreenCO2" project, supported by the Austrian Climate and Energy Funds, the separation process will now be further developed and the practical viability of the new concept will be demonstrated at pilot scale at Wien Energie's Simmering power plant. "To selectively capture carbon dioxide from exhaust gases, one would usually use aqueous amine solutions as a liquid solvent," says Gerhard Schöny (Institute of Chemical Engineering, TU Wien). However, these amine solvents have significant disadvantages. One major drawback is that a lot of energy is required to remove the CO2 from the solvent after it has been captured. Furthermore, tall absorption towers are needed so that the amine solvent has enough time to come into contact with the flue gas and to absorb the desired amount of CO2. At TU Wien, a different approach for separating CO2 is being followed. "We are also working with amines," explains Schöny. "But not in liquid form." At TU Wien, a fluidised-bed system is being used, in which solid particles come into contact with the flue gas. The amines – which play an important role when separating the CO2 – are applied to the surface of highly porous particles. Schöny is confident that the disadvantages of separation techniques using aqueous amine solutions can largely be overcome that way. Furthermore, the use of fluidised-bed systems may also result in small sizes of the CO2 separation plant itself, which may lead to further reductions of the CO2 capture costs as compared to current separation techniques. The new CO2 separation process has been in development by TU Wien together with Shell since 2011. It is crucial that the flue gas and the flow of active particles move in opposite directions. "With this basic idea in mind, we designed a reactor consisting of multi-stage fluidized bed columns," says Gerhard Schöny. The flue gas moves from the bottom to the top, whereas the particles adsorb more and more CO2 as they move downwards through the adsorber column. The particles are then directed to the regenerator column. There, they are heated up, thereby releasing the CO2 again. The regenerated particles are then sent back to the adsorber to perform another CO2 separation cycle. A bench scale unit has already been built and is being operated at TU Wien, and the concept now needs to be upscaled to pre-industrial levels. "Our bench scale unit can separate around 50 kg of CO2 every day, but now we want to build a pilot plant that can separate 5 tonnes per day," says Schöny. The bench scale unit has already proven that the principle is sound, as it was possible to capture more than 90% of carbon dioxide. One day, it may be possible to combine these CO2 separation reactors with biomass power plants. This would mean that electricity can be produced in a carbon-neutral way while the released "green" CO2 can be captured and used (CCU). Together with the ViennaGreenCO2 consortium partners, TU Wien wants to clarify the last few technical details over the coming years The pilot plant should be operational by 2018.The carbon dioxide that is separated by the pilot unit will be further processed and used as fertiliser in a test greenhouse run by LGV Frischgemüse.


Wu X.,Institute of Chemical Engineering | Wu X.,Qingdao University of Science and Technology | Zhang B.,Qingdao University of Science and Technology | Hu Z.,Qingdao University of Science and Technology
Materials Letters | Year: 2013

In this study, we successfully established an additive-free microwave hydrothermal (M-H) route by only using Al2(SO4) 3 aqueous solution and urea as raw materials. Core-shell structured boehmite was synthesized at 180°C for the first time via a M-H route. The final product was characterized by techniques of X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscope (SEM). On account of the fact that less reaction time usually means less energy consumption or more eco-friendly design, the M-H reaction time was successfully reduced to only 40 min by utilizing full microwave heating power and appropriate dosage of urea. To investigate the possible mechanism and influencing factors associated with the morphology and crystal form evolution process, samples subjected to different reaction durations were prepared and characterized. © 2012 Elsevier B.V. All rights reserved.


Zhang G.-X.,Institute of Chemical Engineering | Wang Z.-H.,Institute of Chemical Engineering
Xiandai Huagong/Modern Chemical Industry | Year: 2015

The structure and main features of microreactors is introduced. Taking a multi-function set in the integration of microreactor and Corning's seamless scale-up continuous flow reactor as an example, the recent progress of microreactor and its industrial applications are focused. ©, 2015, Xiandai Huagong/Modern Chemical Industry. All right reserved.


Wu X.,Institute of Chemical Engineering | Wu X.,Qingdao University of Science and Technology | Zhang B.,Qingdao University of Science and Technology | Hu Z.,Qingdao University of Science and Technology
Powder Technology | Year: 2013

An additive-free hydrothermal approach has been developed for the large-scale synthesis of lamellar morphology boehmite powders by merely using Al(NO3)3 and urea as raw materials conducted in an autoclave of 10L capacity. The hydrothermal synthetic and calcined products were characterized by techniques of X-ray diffraction(XRD), transmission electronic microscopy(TEM), scanning electron microscope(SEM), Fourier transform infrared spectrometry (FTIR) and thermogravimetric analysis (TGA/DTA). The microscope analysis manifested that the lamellar boehmite was around 100-200nm in width and 500-1000nm in length. The opportune influence factors on boehmite morphology, such as dosage of urea and reaction temperature were determined by single-factor experiment method. To investigate its crystal form and lamellar morphology evolution process, samples subjected to different reaction durations from 2h to 12h were prepared and characterized by techniques of TEM, SEM and XRD. A spontaneous morphology evolution mechanism driven by Ostwald ripening was proposed based on the experimental facts. © 2013 Elsevier B.V.


Wu X.,Institute of Chemical Engineering | Wu X.,Qingdao University of Science and Technology | Zhang B.,Qingdao University of Science and Technology | Hu Z.,Qingdao University of Science and Technology
Powder Technology | Year: 2013

The controlled synthesis of inorganic materials with desired morphologies and architectures at micro- and nanoscale levels is of great importance to inorganic material design. In this study, we describe an innovative morphology control concept named anions competition method. The key point is to introduce another concomitant raw material to not only share the total demand of cations but also provide competitive anions required by the morphology control. Take boehmite for example, aluminum sulfate was consciously and proportionally introduced as another concomitant raw material into aluminum chloride/aluminum nitrate-urea hydrothermal process to form SO4 2--Cl- and SO4 2--NO3 - competition systems. Boehmite from lamellar assemblies to hollow microsphere morphologies was facilely synthesized by succinctly altering the relative proportion of SO4 2-:Cl- and SO4 2-:NO3 -. © 2013 Elsevier B.V.


Wu X.,Institute of Chemical Engineering | Wu X.,Qingdao University of Science and Technology | Zhang B.,Qingdao University of Science and Technology | Wang D.,Qingdao University of Science and Technology | Hu Z.,Qingdao University of Science and Technology
Materials Letters | Year: 2012

Boehmite (γ-AlOOH) hollow microspheres were synthesized via a convenient hydrothermal route. To investigate its crystal form and morphology formation process, samples subjected to different reaction durations from 1 to 24 h were prepared and characterized by techniques of X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscope (SEM). A spontaneous morphology evolution mechanism driven by Ostwald ripening and dissolution-renucleation was proposed based on the experimental facts. We think that systematically understanding and hereby manipulating the morphology evolution process will contribute to fabricate novel morphologies of the materials. © 2011 Elsevier B.V. All rights reserved.


Wu X.,Institute of Chemical Engineering | Wu X.,Qingdao University of Science and Technology | Zhang B.,Qingdao University of Science and Technology | Hu Z.,Qingdao University of Science and Technology
Materials Letters | Year: 2012

The boehmite (γ-AlOOH) hollow microspheres were synthesized after 120 min reaction time at 150°C for the first time via a microwave hydrothermal route, using Al 2(SO 4) 3 aqueous solution and urea as raw materials and amphiphilic copolymer of P(St)-b-P(HEA) as structure-directing agent. The final product was characterized by techniques of X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscope (SEM). The microscope analysis revealed that the boehmite (γ-AlOOH) hollow microspheres were around 1-2 μm in diameter and a shell thickness of approximately 200 nm. To investigate the influencing factors and formation mechanism of the as-obtained boehmite hollow microspheres ultra-fine powders, samples subjected to different reaction durations were also studied by SEM. A self-assembly morphology evolution mechanism was proposed based on the experimental facts. © 2011 Elsevier B.V. All rights reserved.


Kubicek C.P.,Austrian Institute of Industrial Biotechnology | Kubicek C.P.,Institute of Chemical Engineering
Journal of Biotechnology | Year: 2013

Recent progress and improvement in "-omics" technologies has made it possible to study the physiology of organisms by integrated and genome-wide approaches. This bears the advantage that the global response, rather than isolated pathways and circuits within an organism, can be investigated (" systems biology"). The sequencing of the genome of Trichoderma reesei (teleomorph Hypocrea jecorina), a fungus that serves as a major producer of biomass-degrading enzymes for the use of renewable lignocellulosic material towards production of biofuels and biorefineries, has offered the possibility to study this organism and its enzyme production on a genome wide scale. In this review, I will highlight the use of genomics, transcriptomics, proteomics and metabolomics towards an improved and novel understanding of the biochemical processes that involve in the massive overproduction of secreted proteins. © 2012 Elsevier B.V.


Derntl C.,Institute of Chemical Engineering | Kiesenhofer D.P.,Institute of Chemical Engineering | Mach R.L.,Institute of Chemical Engineering | Mach-Aigner A.R.,Institute of Chemical Engineering
Applied and Environmental Microbiology | Year: 2015

The state-of-the-art procedure for gene insertions into Trichoderma reesei is a cotransformation of two plasmids, one bearing the gene of interest and the other a marker gene. This procedure yields up to 80% transformation efficiency, but both the number of integrated copies and the loci of insertion are unpredictable. This can lead to tremendous pleiotropic effects. This study describes the development of a novel transformation system for site-directed gene insertion based on auxotrophic markers. For this purpose, we tested the applicability of the genes asl1 (encoding an enzyme of the L-arginine biosynthesis pathway), the hah1 (encoding an enzyme of the L-lysine biosynthesis pathway), and the pyr4 (encoding an enzyme of the uridine biosynthesis pathway). The developed transformation system yields strains with an additional gene at a defined locus that are prototrophic and ostensibly isogenic compared to their parental strain. A positive transformation rate of 100% was achieved due to the developed split-marker system. Additionally, a double-auxotrophic strain that allows multiple genomic manipulations was constructed, which facilitates metabolic engineering purposes in T. reesei. By employing goxA of Aspergillus niger as a reporter system, the influence on the expression of an inserted gene caused by the orientation of the insertion and the transformation strategy used could be demonstrated. Both are important aspects to be considered during strain engineering. © 2015, Derntl et al.

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