Chemical

DSM,specialty chemical

Suspension melt crystallization produces crystal material with high purity due to the low rates of crystal growth which are typical for this technology. The low growth rate results in a high selectivity with respect to the incorporation of molecules of the crystallizing component into the crystal structure. Combined with the effective separation in the wash column , removing all adhering mother liquor from the crystal surface, the process is capable of producing high purity in a single process step.

 purification of paraxylene

Many chemicals that are currently purified through distillation or layer crystallization  are potentially suited for the advantageous use of Freeze Tec  technology. In general the chemicals should meet the following requirements:

• Liquid viscosity at  crystallization temperature   <    20 mPa.s   (generally the lower the better in terms of more throughput )
• Crystallization temperature in the following range:    - 30 ºC  < Tcryst <  +100 ºC  ( lower temperatures are not impossible but  the energy cost for cooling increases substantially; higher temperatures may exclude  the use of common construction materials)
• The crystallizing component must form crystals that have a certain mechanical strength to withstand the mechanical forces in the washcolumn.                              

Huntsman,MDI

Examples of chemicals that meet the requirements and are successfully produced in commercial or pilot equipment are:

• Tertiary Butyl Alcohol
• Paraxylene
• Metaxylene
• Ethyl Lactate
• Dilactide
• Paradichlorobenzene
• Caprolactam
• Lactic Acid
• Methyldiphenyldiisocyanate
• Acrylic Acid
• Other ( non disclosed because of secrecy agreements)

The fastest and most cost effective way to find out if a chemical can be successfully produced using our technology is by doing a test with our range of pilot plants.