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Abstract: The present article embraces the photocatalytic oxidation (PCO) of three selected cyclohexyl alcohols namely cyclohexylmethanol (1), 2-cyclohexylethanol (2) and 1-cyclohexylethanol (3) using nanoparticles titanium dioxide (TiO2-P25) as a semiconductor photocatalyst in acetonitrile under aerated conditions. The photocatalytic experiments showed moderate conversion ratios (55.2%, 51.8% and 60.3%, respectively). The primary photocatalytic oxidation products are the corresponding aldehydes or ketones and acids. The photocatalytic oxidation products were identified mainly by GC and GC/MS techniques using authentic samples. Formation of electron–hole pair at the surface of the semiconductor nanoparticles followed by oxidation reaction was the suggested mechanism. A first-order kinetic model was observed for the photocatalytic oxidation of the investigated alcohols and the rate constants were calculated. [Copyright &y& Elsevier]

Photocatalytic oxidation of the title compounds 1 and 2 in nonaqueous oxygen saturated TiO2 suspension was carried out. The corresponding ketones were formed in a high yield, in addition to minor amount of the corresponding hydrocarbon and other decomposition products. Interestingly, photocatalytic oxidation of the parent fluorene (3) afforeded fluorenone under the same conditions. Also, compound 4 as an acyclic simulant gave the corresponding ketone and hydrocarbon. Furthermore, the effect of solvent polarity has been tested.An electron–hole pair generated on the irradiated TiO2 surface is suggested for the semiconductor-mediated photocatalysis. [Copyright &y& Elsevier]

Photocatalytic oxidation of selected aryl alcohols (1–7) has been carried out by using anatase titanium dioxide catalyst. The main oxidation products were the corresponding aldehydes or ketones and acids, in addition to unidentified minor compounds. Kinetic studies revealed a second-order reaction rate for benzyl alcohol, as a model alcohol, photocatalytic oxidation. The suggested mechanism envisages electron–hole pair formation on the catalyst surface followed by oxidation–reduction reactions. [Copyright &y& Elsevier]

• Green Co 3 O 4 /SF-MCM-41 photocatalyst was synthesized from silica fume and Pomegranate leaves. • It is of enhanced photocatalytic properties than Co 3 O 4 in the oxidation of Omethoate pesticide. • It is achieved 100 % oxidation percentage for 50 mg/L of Omethoate after 30 min under visible light. • The results revealed presences of organic intermediate compounds during the oxidation stages. • All the formed intermediate compounds were transformed into NO 3 −, SO 4 2-, PO 4 3, and CO 2. Advanced nanocomposite from silica-fume based MCM-41 and cobalt oxide (Co 3 O 4 /SF-MCM-41) which precipitated by green techniques in the presences of Pomegranate leaves extract as reducing reagent. The formation of the Co 3 O 4 /SF-MCM-41composite was confirmed by different studied analytic techniques and applied as novel photocatalyst in the visible light oxidation of Omethoate pesticide. The composite is of stunning surface area (742 m2/g) and low band gap energy value (1.53 eV) which giving it promising photocatalytic performances. It showed highly effective photocatalytic activity which reflected in a complete degradation of 50 mg/L, 100 mg/L, 150 mg/L, 200 mg/L and 250 mg/L of Omethoate after 30 min, 50 min, 80 min, 100 min, and 120 min, respectively using 0.25 g of Co 3 O 4 /SF-MCM-41. This associated with complete degradation of the detected TOC content within the same time intervals. The detected intermediate organic materials of (CH 3 O) 3 P(O), (CH 3 O) 2 P(O)SCH 3 , CH 3 NHC(O)CH 2 SH, CH 3 NHC(O)CH 2 SCH 3 , and NH 2 C(O)CH 2 SCH 3 were identified as oxidizing products during the degradation steps and all of them were converted into NO 3 −, SO 4 2-, PO 4 3-, and CO 2 as final products. The composite is of reusability value and the hydroxyl radicals were identified as the controlling radicals during the oxidation process. [ABSTRACT FROM AUTHOR]