ENERGY AND THE ENVIRONMENT
Professors Chang, Cohen, Hicks, Manousiouthakis, Monbouquette, Nobe, Senkan and Liao
The growing public concern about environmental protection is having a significant impact on the political and economic activities in the U.S. and around the world. Consequently, there is an increasing pressure on the scientific and engineering communities for the development of clean, environmentally friendly technologies, while maintaining our high living standards. The Chemical Engineering Department at UCLA has had a long and distinguished record of making pioneering contributions to Environmental Chemical Engineering and has been the hub of environmental research for over a decade. Today, most of the faculty conducts research related to environmental protection, and the Department prides itself for leading the development of scientific and engineering principles for the rational design of clean technologies of the future.
The Air Quality/Aerosol Technology Laboratory under the direction of Professor Friedlander conducts fundamental research on the characterization and dynamics of aerosols. Aerosol technology is a central issue in modern air pollution engineering because of recently discovered serious health effects associated with atmospheric concentrations of particles. Fine particles in the atmosphere originate either from pollutant gases via chemical reactions or are emitted directly from sources, such as combustion, both natural and anthropogenic. In addition, chemical reactions on fine particle surfaces are germane to a number of additional practical problems such as ozone destruction in the upper atmosphere and dioxin formation in incinerators.
Combustion provides over 70% of our energy production today, yet it is also the principal contributor to air pollution. The Combustion Research Laboratory (CRL), under the direction of Professor Senkan, focuses on fundamental chemical kinetic issues related to the formation and control of toxic combustion by-products, such as aromatics, polycyclic aromatic hydrocarbons (PAHs) and chlorinated dioxins. CRL investigators are developing new experimental techniques and are pushing the boundaries of our understanding of premixed and diffusion flame structures. These studies are generating unprecedented detail on flame chemistry and aiding the development of fundamentally based chemical kinetic mechanisms describing the formation and destruction of pollutants in combustion and other reaction processes. CRL investigators recently discovered that contrary to popular belief, ethane rather than methane, the major component in natural gas, is the cleanest burning hydrocarbon fuel. Related research on the incineration chemistry of hazardous materials, such as halogenated hydrocarbons, is also undertaken in the CRL for the advancement of incinerator technology.
Power Generation Plant at UCLA
Environmental issues also affect the rapid growth of microelectronics manufacturing, and our department is spearheading the development of cleaner technologies for this industry. For example, Professor Hicks is developing a new generation of metalorganic chemical vapor deposition reactors with minimal discharge of waste by-products. Professors Chang and Hicks are also vigorously pursuing research programs to develop solvent-free technologies, such as plasma cleaning, for the microelectronics industry.
Advanced instrumentation is crucial for controlling process performance and emissions, as well as for monitoring pollutants in the environment. Chemical engineering faculty are pioneering the development of new measurement methods. The Aerosol Technology Laboratory investigators are collaborating with Chemistry faculty on the design of novel instrumentation for on-line monitoring of the chemical composition of polydisperse aerosols using Raman Spectroscopy. Applications include process control for the minimization of undesirable emissions and rapid source resolution of ambient air quality. Also underway is a collaborative study (with Chemistry) on the detection of strong oxidizing agents present in atmospheric aerosols. The investigators in the CRL are developing a highly sensitive, real-time detector based on Resonance Enhanced Multi-Photon Ionization (REMPI) of molecules coupled to Time-of-flight Mass Spectrometry (TOF/MS). The REMPI-TOF/MS promises to be a universal detector because of its sensitivity, versatility and broad mass range, and has applications in process and air quality monitoring. In addition to volatile organics, the system has been used to detect semi-volatile species such as PAHs, fullerenes, metals and even large biomolecules. The REMPI-TOF/MS developed in the CRL has already produced some impressive results such as the real time detection of naphthalene at the part per trillion (ppt) level, using a single laser shot.
Time-of-flight Mass Spectrometry
The recovery of trace level constituents from process and waste streams presents unique opportunities for innovative research in process separations. In the Biochemical Engineering Laboratory of Professor Monbouquette, novel biomimetic vesicular membranes are being developed for the continuous removal and recovery of heavy metal ions from dilute aqueous solutions. These metal sorbing vesicles can capture and concentrate metals 100-1000 fold thereby providing an excellent means of minimizing heavy metal emissions with the added benefit of metal recovery for a variety of industries. At the Polymer and Separations Research Laboratory of Professor Cohen, a new class of ceramic-supported polymer membranes is being developed for the decontamination of aqueous systems and for the separation of organic liquid mixtures. Fundamental research on polymer brush layers has also led to the recent development of a new class of low-fouling ultrafiltration membranes for colloidal and protein separations and novel pervaporation membranes.
The Multimedia Environmental Analysis (MEA) Laboratory of Professor Cohen explores complex interactions of pollutants with various environmental media (e.g. air, water, soil, vegetation) and the relationship between molecular structure and physicochemical properties of synthetic chemicals. Research at the MEA laboratory is providing a better basis for the rational assessment of both the risks induced by pollutant discharges and life cycle analysis of products. For example, as part of a national effort, UCLA investigators, developed a set of integrated multimedia models to assess the partitioning of volatile and particle-bound pollutants in the environment. More recently, novel and highly accurate neural network-based quantitative-structure-property relations (QSPRs) have been developed for environmentally relevant physicochemical properties. These advanced tools have already demonstrated their utility for evaluating potential environmental problems associated with atmospheric transformation products of polycyclic aromatic hydrocarbons and in retrospective analysis of PCB contamination in aquatic systems.
Energy and the environment are the two overriding themes guiding the efforts of Manousiouthakis' group to redesign industrial facilities. The group has developed a number of methodologies that can aid engineers in designing plants that are using their material and energy resources efficiently so as to be both economically viable and environmentally friendly. In this spirit, a heat and power integration methodology is developed that can identify the minimum heating, cooling and electric utility cost for any given facility. An Infinite DimEnsionAl State-space (IDEAS) optimization approach is also being developed that can automatically synthesize cost-optimal process networks that meet energy and environmental goals. The power of IDEAS stems from its ability to optimize over all possible process networks and to guarantee the global optimality of the obtained solutions. Applications to date have focused on the synthesis of energy efficient distillation networks, multicomponent mass exchange networks, membrane networks and reactor networks. Major achievements have already been made by the Manousiouthakis' group in the area of green manufacturing, with the introduction of advanced concepts, such as mass exchange networks, for the minimization of raw material and water use and for the reduced generation of chemical waste.
The Department offers an exciting series of graduate courses providing in-depth exposure to areas in aerosol technology, air pollution, environmental assessment, environmental transport phenomena, pollution prevention and waste minimization, and combustion processes. In addition, students can pursue a minor field of study in any environmentally related discipline to further enhance their education. The Chemical Engineering program on energy and the environment is interdisciplinary, and graduate students benefit from relevant courses offered by many other departments at UCLA. Program activities involve the close participation of select faculty from other departments such as Applied Mathematics, Chemistry and Biochemistry, Civil Engineering, Mechanical Engineering, Physics, Atmospheric Sciences and the School of Public Health. The Department faculty also interact closely with Industry and Government Agencies, so as to help focus departmental research and teaching programs on real-life environmental problems and concerns thereby preparing our students for successful careers in the private and public sectors and in academia.