Effect of salts, pH, type of acids and anion sulphate in the synthesis and separation of phenol through the hydroxylation of benzene by using a Fenton reaction in a biphasic membrane contactor has been investigated. The results indicated that sodium sulphate (1 M) increased phenol extraction in the organic phase (76.3%) but also increased reaction kinetics promoting over-oxidation products and a black solid (tar) formation. The acids delayed and in some tests avoided the tar appearance as precipitate but also gave a reduction of phenol selectivity. The sulphate absence, obtained by using iron(0), did not avoid the precipitate formation but only caused its decrease favouring a significant increase of the ratio productivity/amount of black solid from 4.6 to 62.4. Keywords: liquid phase benzene oxidation to phenol, catalytic membrane contactor, selective oxidation, tar formation from benzene, salts and phenol extraction (from aqueous to organic).
Selectivity control of benzene conversion to phenol using dissolved salts in a membrane contactor".
MOLINARI, Raffaele;
2011-01-01
Abstract
Effect of salts, pH, type of acids and anion sulphate in the synthesis and separation of phenol through the hydroxylation of benzene by using a Fenton reaction in a biphasic membrane contactor has been investigated. The results indicated that sodium sulphate (1 M) increased phenol extraction in the organic phase (76.3%) but also increased reaction kinetics promoting over-oxidation products and a black solid (tar) formation. The acids delayed and in some tests avoided the tar appearance as precipitate but also gave a reduction of phenol selectivity. The sulphate absence, obtained by using iron(0), did not avoid the precipitate formation but only caused its decrease favouring a significant increase of the ratio productivity/amount of black solid from 4.6 to 62.4. Keywords: liquid phase benzene oxidation to phenol, catalytic membrane contactor, selective oxidation, tar formation from benzene, salts and phenol extraction (from aqueous to organic).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.