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. These
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. Clients of Crystallization Consulting include Eastman Kodak, Xerox, Johnson & Johnson,
Dow Chemical, Cabot, Southern Clay Products, Sachem, TempTime, Akzo-Nobel, and others.
How You Will Benefit from This Course:
Understand
the principles that control crystal size in precipitations.
Understand and control the size and size distribuiton of
nanoparticles and larger particles.
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.
Learn a quantitative and self-consistent crystallization model for batch and continuous precipitations.
Who Should Attend:
Chemists, chemical engineers, and other scientists who need to control precipitation processes for size and size distribution will benefit from the material. The information is essential for those who are involved in crystallization 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 model based on balanced nucleation and growth (BNG)
General quantitative model
Nucleation rate, crystal number
Size distribution
Nanoparticles
Nucleation under diffusion controlled growth conditions
Quantitative effect of basic reaction parameters during nucleation and experimental examples
Molar/mass addition rate
Solubility
Temperature
Ostwald ripening agent
Growth restrainers
Nucleation under kinetically controlled growth conditions
Heterogeneous nucleation and renucleation in batch processes
The Randolph – Larsen Model
The Balanced Nucleation/Growth Model
Controlled crystal growth in the CSTR crystallizer
Instructor
Dr. Ingo H. Leubner has over twenty-five years experience in the precision precipitation
of crystals for product applications. In the imaging industry he was responsible for the
precision precipitation of silver halide particles for commercial products. He consulted on
the precipitation of dye particles, which have potential use as pigments. He is founder and
senior scientist for Crystallization Consulting, a company specializing in consulting,
modeling and teaching of advanced models for controlled high-precision precipitations. He
consulted among others with pharmaceutical, imaging, and inorganic, and organic industrial
companies. He taught courses at industry, academic institutions, and at conferences. He is
continuing to expand the BNG model. Dr. Leubner received a Ph.D. in Physical Chemistry from
the Technical University in Munich (TUM) on the relationship between the molecular structure
and color of dyes. He continued his studies with a post-doctoral fellowship at TUM. At Texas
Christian University, Fort Worth, Texas, he held the position of R. Welch Fellow studying
photochemistry of benzene and benzene derivatives. 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 precision 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, the American Association for the Advancement of Science, the American
Geographical Union, the Rochester Professional Consultants Network, Torrey Pines Research, and
High-Technology of Rochester.
(C) 2005 Particles Conference