Ahmed Sabry Abdel-Rahman

The present study deals with constructing an automatic low-cost crystallizer system. The study
of the produced sample is important to judge the performance of the constructed unit. A well-known TGS
(Tri-Glycine Sulfate) sample was grown and some physical properties of the produced crystal were
measured should be compared with another resemble published results. The growth of TGS crystal is
affected by programmable temperature decrease method, where the solubility decreases as the
temperature be lowered thus the cooling of a supersaturated solution will often produce crystals. Since
rapid cooling may cause the precipitation of amorphous solid or parasite crystals, it is advisable to
surround the crystal growth apparatus with an insulating medium to slow down the rate of cooling (a
foam covering is used in our study.)
Growth program takes nearly 10 to 12 days and is automatically driven by computer which
controls all the growth conditions like stepper motor speed, regulation of temperature decrease (0.5ºC
each 12 hours). The speed of the stepper motor according to the program is 30 RPM (rotation per minute)
in first five days of growth and 15 RPM afterwards.