© 2021 JETIR May 2021, Volume 8, Issue 5 www.jetir.org (ISSN-2349-5162)
JETIR2105591 Journal of Emerging Technologies and Innovative Research (JETIR) www.jetir.org d375
EFFECT OF TEMPERATURE AND
PROCESSING TIME ON AGGLOMERATES
PREPARED BY SPHERICAL
CRYSTALLIZATION
1
Vijaya Laxmi Avula,
2
Mounika K,
3
Jyothi Thati,
4
Sailu Chintha
1
Assistant Professor,
2
Student,
3
Assistant Professor,
4
Professor
Department of Chemical Engineering, University College of Technology (A),
Hyderabad, Telangana, 500007, India
*Corresponding Author Email: kattajyothi@gmail.com
Abstract: Spherical Crystallization process incorporates crystallization and agglomeration simultaneously in one step. In this
study benzoic acid agglomerates in spherical shape are prepared using anti solvent crystallization method with methanol-water-
toluene system. Here benzoic acid is dissolved in methanol to prepare a saturated solution and this solution is added to water as an
anti-solvent to crystallize the benzoic acid and 3
rd
solvent used to collect the individual crystals and agglomerate them. Under
continuous agitation, the particles become spherical shaped agglomerates due to shear force.
In this work influence of temperature on spherical agglomeration of benzoic acid was studied and observed that with increasing
temperature average agglomerate size was decreased. Particle size distribution and morphology improved with increasing process
time at different temperatures. The total number of particles with residence time is calculated and found that the total number of
particles decreased with increasing residence time, but become denser and bigger with time.
In this work mainly solvent system has been changed and proven that it is possible to use different solvents as good solvent.
kinetics has been found. Influence of temperature and processing time on Spherical crystallization of benzoic acid in Methanol -
water -toluene system studied and found to have influence on the agglomerate growth. Kinetics has been found for the
agglomerate growth rate and agglomeration process was described by first order kinetics.
IndexTerms - Spherical Agglomeration, Crystallization, Morphology, Particle size.
I. INTRODUCTION
Crystallization is a separation and purification technique, in which solid crystals are formed from a liquid solution. Most of
the Pharmaceuticals, food and chemical industries are using the crystallization method to separate solid crystals from solution.
Spherical Crystallization is a novel crystallization technique that could transform fine crystals into spherical agglomerates during
crystallization. In this process as crystallization solvent three partially miscible solvents are used. The first solvent was used to
dissolve the solute, second was used for crystallization and the third solvent was called a bridging liquid to promote the
agglomerates formation [8, 9]. This solvent preferentially wets the crystals produced and aggregates them into agglomerated
spherical form. [13,14] Gave a detailed mechanism about how the bridging liquid collects the multiple crystals by capillary forces
and form an aggregate by forming liquid bridges between them then to spherical form by the action of shear force. As parameters
like solute concentration, temperature, amount of bridging liquid, feed rate, processing time etc., have great impact on the
spherical agglomeration many authors studied the influence of these process parameters for different compounds
[1,2,7,10,11,12,14,16]. Kinetics of the spherical agglomeration has not been explained much in literature, in this work an attempt
was made to explain the kinetics using number of particles formed at different temperatures and process time.