Sulphur residual atmosphere

Residues (petroleum), heavy coker and light vacuum Residues (petroleum), catalytic reformer fractionator Residues (petroleum), hydrodesulphurized atmospheric tower Residues (petroleum), topping plant, low sulphur Residues (petroleum), heavy coker gas oil and vacuum gas oil Residues (petroleum), thermal cracked... 

Dibenzotellurophene Tellurium powder (6 g, 47 mmol) and dibenzothiophene S.S -diox-ide (8 g, 37 mmol) are mixed thoroughly, the mixture is carefully heated under an atmosphere of carbon dioxide until evolution of sulphur dioxide commences, and the temperature is then regulated to achieve a steady evolution of sulphur dioxide. From time to time the sublimed dibenzothiophene dioxide is melted and allowed to flow back into the reaction mixture. After 36 h, the mixture is cooled to 20°C and extracted with boiling acetone. The extract is evaporated to dryness, the solid residue is washed several times with cold ethanol, and the washings are collected and evaporated. The residue is steam distilled and the product is recrystallized from light petroleum ether. Yield 1.0 g (10%) m.p. 93°C. 

---