This course offers new concepts and quantitative models which are vital to those who need precision control of crystal size in products. The crystal size is a function of both crystal nucleation and growth. Control of nucleation is the most challenging factor. Classical nucleation theories do not give precise guidance to control crystal nucleation. Solutions to specific problems are generally obtained by trial and error. We have developed new models and equations that relate the crystal number and size distribution (nucleation) to experimentally controlled reaction variables. In the models, the crystal number is quantitatively related to reactant addition rate, crystal solubility, temperature, and solvent and crystal properties. It also models the effect of other factors like crystal ripening agents and crystal growth restrainers. For the first time, equations for both controlled batch and continuous precipitations were developed using the same model. Unexpected predictions were experimentally confirmed. The new concepts can be applied to the precipitation of inorganic materials such as silver halides in the photographic industry, and of organic systems such as latexes, dyes, and pigments. Other applications are in pharmaceuticals, catalysis, imaging systems, separations, and surface modifications. Because this work is at the cutting edge of crystallization science and technology, this information is not yet available from textbooks and academic institutions. Thus, the course provides a unique opportunity to learn up to date principles for precision controlled precipitations.
How You Will Benefit from This Course:
Understand
the principles that control crystal size in precipitations.
Learn advanced principles to solve precipitation
problems in batch and continuous processes.
Quantitatively relate the crystal size to
the precipitation variables.
Learn to minimize the number of experiments
in precipitation R&D and product development.
Learn to predict process limitations and
breakdowns.
Control competitive heterogeneous and homogeneous
nucleation in precipitations.
Who Should Attend:
Chemists, chemical engineers, and other scientists who need to control precipitation processes and who are involved in R&D, quality control, design, development, production processes, pilot plant operations, and manufacturing. Basic knowledge of physical chemistry, chemical engineering, some knowledge of calculus and of process fundamentals is helpful.
Review of classical crystallization models
Principles of crystallization codel based on calanced growth/nucleation General quantitative model
Nucleation rate, crystal number, and crystal size distribution
Nucleation under diffusion controlled growth conditions
Quantitative effect of basic reaction parameters during nucleation and experimental examples Molar/Mass addition rate
Solubility, Temperature
Special nucleation modifiers: Ostwald ripening agents
Nucleation under kinetically controlled growth conditions
Special nucleation modifiers: Growth restrainers
Heterogeneous nucleation and renucleation in batch processes
The Randolph – Larsen Model
The Balanced Nucleation/Growth Model
Competitive heterogeneous and homogeneous systems
Instructor
Dr. Ingo Leubner has over twenty years experience in the precision
precipitation of crystals for product applications. He is currently
senior scientist for Crystallization Consulting, a company specializing in
consulting, modeling and training in high-precision precipitation technology.
Dr. Leubner received a Ph.D. in Physical Chemistry from the Technical University
in Munich. He continued his studies with a post-doctoral fellowship.
At Texas Christian University, Fort Worth, Texas, he held the position of
R. Welch Fellow studying photochemistry. From there, he accepted a position
as research scientist at Eastman Kodak Company, working in photographic and
precipitation science and product development. He was team-leader for
the development of commercially successful products. He is an experienced
author, lecturer, scientist, and technical project manager. His work
on the precipitation of silver halides for the development of photographic
films and papers led to new insights, theories, and models for the control
of crystal nucleation. He has given presentations and seminars at national
and international conferences, major universities and industries. His
publications, presentations, and seminars resulted in national and international
recognition. He received numerous awards and honors, including the Lieven-Gevaert
Medal for outstanding contributions to photographic science, and the
Fellowship and Service Awards from the Society for Imaging Science and Technology.
He is listed in American Men and Women in Science and in Who’s Who in Science
and Engineering. He is a Fellow of Sigma Xi, and a member of
the American Chemical Society, the Society for Imaging Science and Technology,
and the American Association for the Advancement of Science.
(C) 2004 Particles Conference