Seminars

JERRY W. KING, Emeritus Professor, University of Arkansas

Title: Critical Fluids at the Interdisciplinary Interface in Engineering

Seminar invitation-Prof King

JERRY W. KING, Emeritus Professor, University of Arkansas

Sorry, this entry is only available in Türkçe.

LABORATUVAR DA İŞ SAĞLIĞI VE GÜVENLİĞİ SEMİNERİ

Sorry, this entry is only available in Türkçe.

CHE-Faculty Candidate Seminar -Yard. Doç. Dr. Hakan KAYI

Department of Chemical Engineering

Yard. Doç. Dr. Hakan KAYI

(Chemical Engineering and Applied Chemistry Department, Atılım University, Ankara)

Applications of Computational Chemistry

Date: 25.01.2015, Monday

Time: 10:30

Venue: Department fo Chemical Engineering, Seminar Room

Abstract:

Computational chemistry is primarily concerned with modeling and simulation of real chemical systems in order to understand their behavior, and calculation of data that are sometimes not available experimentally and, more recently, with prediction of properties and behavior before experiments are performed. Research highlights in computational chemistry almost always involve predictions that are later confirmed by experiment or theoretical models that lead to a better understanding of experimental results. Computational chemistry techniques have been used mostly in the life sciences but the design, modeling and simulation of new materials and devices are becoming everyday more important and more popular, especially for engineering applications. Computational chemistry can be considered to be both old and young. It is old since the development of quantum mechanics happened in the beginning of twentieth century. On the other hand, it is young because computer technology developed tremendously over the last 30 years. Recently, computers with increased CPU number and speed, large memory, parallelized algorithms and new methods have helped computational scientists to deal with the broad field of chemical problems. In this presentation we will discuss the utilization of computational chemistry techniques in the solution of some chemical and engineering problems from polymer design and characterization to carbon dioxide capture by organic liquids.

CHE-Faculty Candidate Seminar-Dr. Alican Kızılkaya

Department of Chemical Engineering

Dr. Alican Kızılkaya

Modelling Fischer-Tropsch Synthesis catalysts: An interdisciplinary approach”

Date: 18.05.2016, Wednesday

Time: 15:00

Venue: Department fo Chemical Engineering, Seminar Room

Abstract:

.  Fischer-Tropsch Synthesis (FTS) [the conversion of synthesis gas to synthetic liquid fuels] is an elegant and compelling research field in energy industry: The reactant mixture, called synthesis gas, is predominantly a mixture of CO and H2 and can be obtained from major hydrocarbon sources such as coal, natural gas and biomass. The product mixture consists of linear hydrocarbons, such as paraffins, olefins and waxes, oxygenated species, such as alcohols, aldehydes and acids, branched products, carbon dioxide and water. From an academic point of view, the reaction mechanism is widely debated and one of the most important research areas in heterogeneous catalysis. Industrially, maximizing the selectivity to long chain paraffins or to olefins is of critical importance to increase the financial viability of the process and thus investigated by global energy companies that apply FTS in industrial scale such as Shell and SASOL.

During my talk, I will show how a combination of different approaches, experimental surface science, computational modelling and kinetic modelling, can provide detailed insight about some important issues in cobalt catalyzed FTS. The industrially observed ammonia poisoning of cobalt catalysts will be related to ammonia decomposition on the defective sites on the cobalt surface and the blocking of these sites that are normally active for CO decomposition by strongly adsorbed NHx species. I will also demonstrate that with a similar methodology, we can derive an experimental activation barrier for a key elementary step of the synthesis, water formation. Finally, I will present a future outlook about how this interdisciplinary view can help us explore the factors that control the selectivity in cobalt and iron catalyzed FTS.

 

References

  1. Kızılkaya, A.C., Niemantsverdriet J.W., Weststrate C.J., J. Phys. Chem. C, 2016, 120, 3834-3845.
  2. Kızılkaya, A.C., Niemantsverdriet J.W., Weststrate C.J., J. Phys. Chem. C, 2016, 120, 4833-4842.

CHE-Faculty Candidate Seminar-Hilal Ezgi Toraman

Department of Chemical Engineering

By

 

Hilal Ezgi Toraman

 

Ghent University, Laboratory for Chemical Technology

 

 

Nothing goes to waste: fast pyrolysis of complex feedstocks for the circular economy

Date: 29.08.2016, Monday

Time: 10:30

Venue: Department fo Chemical Engineering, Seminar Room

 

 

Abstract

Laboratory of Chemical Technology, Ghent University, Ghent, 9052, Belgium

The current economic system which is based on a linear consumption pattern “takeproduce-consume-discard” depends on the availability of huge amounts of finite resources. Since it is not possible to sustain such a system on the long term, there is an increasing interest to develop a sustainable and an environmentally friendly economic system which is based on a circular consumption pattern “take-produce-consume-reuse/recycle/(bio)degrade”, i.e. the circular economy. Pyrolysis is considered as a promising technology for the production of fuels and chemicals from renewable feedstocks, e.g. biomass and waste streams, e.g. plastic waste. Although the pyrolysis process is relatively simple and robust, it is not straightforward to use or integrate pyrolysis processes in the current fossil based chemical industry. The latter was developed for feedstocks low in oxygen content, differing substantially in terms of chemical and physical properties. In this seminar, an overview of the studies performed to improve the current understanding of fast pyrolysis of complex feedstocks for the circular economy will be given. This comprises three aspects: (1) development of chromatographic methodologies for the detailed quantitative compositional characterization of pyrolysis oils based on GC × GC – FID/SCD/NCD/TOF-MS, (2) improvement of the current understanding of the effect of biomass composition on bio-oil composition using genetically engineered poplars, and (3) development of a new micropyrolysis setup for measuring intrinsic kinetics which consists of a tandem isothermal pyrolysis reactor coupled with comprehensive analytics.

CHE-Faculty Candidate Seminar-Assist. Prof. Dr. Suha Orçun Mert

Assist. Prof. Dr. Suha Orçun Mert

 

Date: 19.09.2016–Monday

Time: 14:30

Venue: Department of Chemical Engineering, D8

 

 

Abstract

Performance Analysis and Control of Chemical Processes and Energy Systems with Simulation and Modelling

 

The global increase on energy demand and related costs urge the researchers to find ways of sustaining higher efficiencies and lowering the costs in all kinds of processes through world. Chemical processes and energy systems are amongst the most important of such cases, as they are employed in comparatively more energy intensive sectors. On a related note, with radical improvements in computer technology and evolved understanding of modelling and simulation software, these systems became easier to virtually develop and to mathematically solve. Furthermore, when energy and exergy analysis approaches are integrated on top of these modelling and simulation efforts considering their indispensability in identifying sources of energy losses of processes, the true system performances of such systems can be revealed in a much higher clarity beforehand, along with related costs for the structure. This presentation will try to explain modelling, simulation, optimization and control stages of selected fuel cell types and heat transfer systems by means of in-house developed computer programs (MULOP, DISMO, etc.), Matlab based solutions and COMSOL Multyphysics simulations. Some undergoing and planned projects will also be introduced within this framework.

CHE-Faculty Candidate Seminar-Erdal UZUNLAR

A Researcher’s Journey on Electronic Materials, Processes and Devices

By

 Erdal UZUNLAR 

Date: 19.10.2016–Wednesday

Time: 15:30

Venue: Department of Chemical Engineering, Seminar Room

 

 

 

Abstract

The overarching focus of my research is on electronic materials, processes and devices. My journey begins with the development of microcantilever-based sensors for simultaneous density and viscosity measurement in gaseous, liquid and supercritical carbon dioxide. Changes in oscillatory response of such devices when immersed in fluids contain useful information about the thermophysical properties of the surrounding media. Here, I will present the sensor, and its experimental and theoretical validation. The journey continues with the electroless deposition of copper on printed circuit boards which is important for fabrication of chip-chip interconnects, i.e. conductive highways that transmit signal between chips. Conventionally, electroless deposition is facilitated by an expensive catalyst, and the adhesion is generally achieved by mechanical interlocking of the deposited layer to an intentionally roughened surface. Here, I will present a novel method that enables electroless copper deposition using an inexpensive yet equally active catalyst. A simple surface pre-treatment technique that does not introduce additional surface but amplifies chemical adhesion will also be introduced. The last topic I will present is on organic thermoelectric materials which are metallo-organic molecules that convert heat to electricity. Unlike their inorganic counterparts, these metallo-organic compounds have advantages such as flexibility, inherently low thermal conductivity, and abundance of its constituent elements. Here, I will talk about the first systematic synthesis of these metallo-organic compounds, and their thorough thermoelectric and chemical binding environment characterization. Lastly, I will introduce my future research plan.

 

Biography

Erdal Uzunlar received his undergraduate degree in Chemical Engineering at Bogazici University in 2008, and his Master’s degree in Chemical and Biological Engineering at Koc University in 2010. During his Masters under the supervision of Prof. Can Erkey, he studied microcantilever-based sensors for simultaneous measurement of density and viscosity in gaseous, liquid and supercritical carbon dioxide. He earned his PhD degree in Chemical Engineering in 2015 at Georgia Institute of Technology in Atlanta, Georgia, USA. During his PhD under the supervision of Prof. Paul A. Kohl, he investigated materials and processing improvements for chip-chip interconnects and micro-electro-mechanical systems packaging. He has a PhD minor in Electromagnetics and Microwave Engineering. He continued his research career as a postdoctoral fellow in Chemistry at Georgia Tech in Prof. John R. Reynolds’ research group. During the postdoc, he explored organic thermoelectric materials for low-temperature waste energy harvesting. His overarching future research focus will be on electronic materials, processes and devices.