K. Meera

Enhancement of metastable zone width for solution growth of potassium acid phthalate

A new method has been developed in which the addition of a small amount of ethylenediamine tetra acetic acid (EDTA), a well-known chelating agent, enhances the metastable zone width significantly. Also, it has been found that this addition reduces the rate of nucleation and increases the growth rate of the crystal. This method has been employed for solution growth of potassium hydrogen phthalate (KC8H5O4), which is also known as potassium acid phthalate (KAP).

A novel method to enhance metastable zone width for crystal growth from solution

A novel method has been found to enhance the metastable zone width of solutions in their supersaturated region in order to grow large size crystals. In which, the incorporation of a small quantity of Ethylenediamine tetra acetic acid (EDTA), a well-known chelating agent, enhances the zone width significantly due to its chelating action. Also this incorporation reduces the nucleation rate and enhances the growth rate of the crystal. X-ray rocking curve experiment for the grown crystals reveals that EDTA addition does not affect the crystalline quality. This concept was first realized with Potassium acid phthalate (KAP) solutions and then confirmed with Potassium dihydrogen phosphate (KDP) and Triglycine Sulphate (TGS).

A contemporary method to enhance the metastable zone width for crystal growth from solution

A contemporary method has been developed to enhance the metastable zone width of the solutions in their supersaturated region in order to enhance their stability to grow large size crystals with faster cooling rates. In which, the incorporation of a small quantity of ethylenediamine tetra acetic acid (EDTA), a well-known chelating agent enhances the zone width significantly due to its chelating action. Also, it is observed that this addition reduces the nucleation rate and enhances the growth rate of the crystal appreciably. This method was adopted in some of the popular crystals grown from solutions such as potassium acid phthalate (KAP), potassium dihydrogen phosphate (KDP) and triglycine sulphate (TGS) and confirmed.

Influence of chelaters in crystallization of K2SO4

The influence of chelating agents like ethylene diamine tetraacetic acid (EDTA), nitrilo triacetic acid (NTA) and dimethyl sulfoxide (DMSO) on potassium sulfate solution has been analyzed. The enhancement of metastable zone width with the addition of chelaters has been observed. The variation of pH with the addition of chelaters has been monitored. The nucleation parameters were calculated from the measurements of the dependence of the metastable zone width on different cooling rates.