Resumen

FOLETTO, E.L.; ALVES, C.C.A.; SGANZERLA, L.R.  y  PORTO, L.M.. Regeneration and utilization of spent bleaching clay. Lat. Am. appl. res. [online]. 2002, vol.32, n.2, pp. 205-208. ISSN 0327-0793.

A spent clay from the oil refining industry was recycled through an extraction process using organic solvents for removal of residual oil, followed by reactivation through heat treatment. The solvents used showed the following order in the efficiency of oil extraction: methylethylketone> acetone > petroleum ether @ hexane. The bleaching efficiency of regenerated clay samples for soybean oil was determined spectrophotometrically in the visible region. For comparison of the bleaching experiments, a sample of virgin commercial clay was used. Results showed that extraction process, using just solvent, is insufficient to recover the bleaching power of the spent clay, needing then a further high temperature treatment. The bleaching power of the regenerated clay is dependent of temperature and time of calcination. The regenerated clay samples presented a similar bleaching efficiency for soybean oil comparable to a virgin commercial clay utilized as reference.

Palabras llave : spent clay; recycling; regeneration; oil recovery.