Dr. Maik Eichelbaum

Current Occupation: Fritz-Haber-Institut der Max-Planck-Gesellschaft (Berlin, Germany), Department for Inorganic Chemistry

Post-Doctoral Research Scientist, Earth & Environmental Engineering,
Columbia University in the City of New York and BASF Catalysts, LLC,
Iselin, NJ
Topic: Urea-SCR with Zeolite Catalysts for Diesel Emission Control

    • Education:
      • PhD in Physical Chemistry (summa cum laude), Humboldt-Universität zuBerlin, Germany; Thesis Advisor: Prof. Klaus Rademann Topic: Synchrotron- and Laser-Induced Growth of Noble Metal Particles in Glasses: Particle Size-Dependent Linear and Nonlinear Photoluminescence (2008)
      • Diplom in Chemistry at Humboldt-Universität zu Berlin, Germany; ThesisAdvisor: Prof. Dr. Klaus Rademann Topic: On the Activated Growth of Noble Metal Clusters with Synchrotron Radiation (2005)
      • Vordiplom in Chemistry at Humboldt-Universität zu Berlin, Germany (2002)
    • Honors and Affiliations:
      • Postdoc grant from the BASF-Columbia University research partnershipprogram “Heterogeneous Catalysis for Environmentally Benign Technologies” (Since 2008)
      • PhD grant from Fonds der Chemischen Industrie (2006 – 2008)
      • Guest Scientist at Federal Institute for Materials Research and Testing(BAM), Berlin, Germany (2004 – 2008)
      • AAAS/Science Magazine Program for Excellence in Science Award (2006 – 2007)
      • 18th Meeting of Noble Prize Winners in Chemistry at Lindau ParticipationAward (2006)
      • Associated Fellow of the Graduate College “Fundamentals and functionalityof size and interface controlled materials: Spin- and Optoelectronics” (2005 – 2008)
  • Description of Research:
    • Diesel engines are an attractive alternative to gasoline internal combustion engines because they operate with high compression ratios and lean air-fuel mixtures making them 20-40% more fuel efficient. However, due to the large amounts of excess air in the exhaust the gaseous, liquid, and solid emissions cannot be abated by simply using the three-way catalyst strategy of gasoline cars. It turned out that especially the simultaneous abatement of both nitrogen oxides (NOx) and particulate matter is challenging, a problem that apparently cannot be solved by improved engine management alone. Since NOx causes ground level ozone (smog), induces the formation of toxic chemicals as well as acid rain, it is therefore regulated in the U.S. by the Environmental Protection Agency (EPA). As NOx standards are becoming more stringent for diesel motor vehicles under the EPA Tier 2 program as well as under the EURO V and VI regulations in Europe, and since there is a trade-off between low NOx emissions and low fuel consumption, the need for NOx abatement technology is growing.In power plants and stationary sources, selective catalytic reduction (SCR) with ammonia (NH3), which transforms NOx into harmless nitrogen (N2) and water vapor, has already proven itself for the successful abatement of NOx in flue gases. Furthermore, the implementation of SCR in diesel vehicles could reduce the fuel consumption by 7% by allowing the engine to be optimized on fuel economy. Thus, SCR bears the potential for building cars and trucks that emit not only less NOx, but less of the greenhouse gas CO2 as well.

      Since NH3 is a reactive and toxic gas it is proposed to use an aqueous solution containing 32.5% by weight urea (also referred to as “AdBlue”) as the NH3 source for SCR in transportation applications due to its non-toxicity and the ability to be carried on board much more easily and safely.

      After the injection of the urea solution into the hot diesel exhaust, urea ideally decomposes into ammonia and carbon dioxide. However, another possible intermediate product of the decomposition is isocyanic acid, which can react to polymeric species such as cyanuric acid, a potential catalyst poison. However, up to now there is nearly no comprehensive information available regarding the impact of urea and its decomposition products on the activity, selectivity, and durability of SCR catalysts.

      Under the umbrella of the BASF-Columbia University joint research initiative “Heterogeneous catalysis for environmentally benign technologies” our research comprehends the investigation of possible, hitherto unknown deactivation pathways of zeolite SCR DeNOx catalysts caused by urea and its decomposition products. The studied catalysts are mainly the commercial zeolites Y, Cu-Y, H-Beta, Na-Beta and Fe-Beta provided by BASF Catalysts, LLC. Simultaneous thermal analysis (STA: TGA, DTA, DSC), GC/MS, and FTIR is carried out to study the influence of zeolite catalysts on the urea pyrolysis and hydrolysis to yield solid and gaseous components. Furthermore, the influence of the identified decomposition products on the activity, selectivity and durability of SCR DeNOx zeolite catalysts is investigated. Zeolites prior and subsequent to the aging tests are studied by means of attenuated total reflection (ATR) FTIR, NH3 and NO2 temperature programmed desorption (TPD), magic angle spinning (MAS) nuclear magnetic resonance (NMR), and electron paramagnetic resonance (EPR) to unravel the underlying deactivation mechanisms.