the production of thymoquinone from thymol and carvacrol

6.1. Materials
CHAPTER 6
EXPERIMENTAL
Metal nitrates (nitrates of Cr(III), Fe(III), Bi(III), Ni(II), Zn(II)), carvacrol (5-
isopropyl-2-methylphenol), thymol (2-isopropyl-5-methylphenol), thymoquinone (2-
isopropyl-5-methyl-p-benzoquinone), salicylaldehyde, 1,3-diamino-propane and
hydrogen peroxide (30%) were purchased from Sigma-Aldrich. Other reagents and
solvents used were HPLC grade and obtained from Sigma-Aldrich. Essential oil was
purchased from Arifo ulları company. Zeolite-NaY (CBV100, SiO2/Al2O3 5.1) that
contained 13.0 wt% Na2O was purchased from Zeolyst International Company in the
form of powder with the sizes less than one micron. The surface area of the zeolite
powder was 900 m 2 g -1 . The unit cell formula of this sample was Na54(AlO2)54(SiO2)138
when dehydrated. Zeolite-NaY was activated at 500 °C in an oven for at 5h and cooled
to room temperature in a desiccator before use.
6.2. Methods
6.2.1. Catalyst Preparations
H2salpn, metal exchanged zeolite Y, and encapsulated complexes were prepared
by following a procedure similar to one described in the literature (Maurya et al. 2002).
6.2.1.1. Preparation of Ligand (H2Salpn)
Salicylaldehyde (12.2 g, 0.1 mol) was dissolved in 65 ml methanol and mixed
with a solution of 1,3-diamino-propane (3.65 g, 0.05 mol) in 25 ml methanol. Solution
was refluxed in a water bath for 1 hour. After reducing the volume of solution to 50 ml,
flask was kept at ambient temperature for 2 hours. Yellow shining plates were filtrated,
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