CWPO of bisphenol A with iron catalysts supported on microporous carbons from grape seeds activation

Abstract

The catalytic wet peroxide oxidation (CWPO) of bisphenol A (BPA) with Fe catalysts supported on activated carbon from grape seeds (GS) has been studied. The GS were pyrolized (N 2 , 600 ºC, 2 h) and subjected to activation upon partial gasification with air (400 ºC, 2 h).Oxidized samples of the char and activated carbon were also obtained upon treatment with HNO 3 . The Fe catalysts were prepared by incipient wetness impregnation with ferric nitrate solution. They showed narrow microporosity, with surface area values ≈ 350-500 m 2 g -1 and total iron contents between 2.8-4.2 % wt. The CWPO experiments were carried out at 50-80 ºC.The best catalyst allowed complete conversion of BPA (100 mg L -1 ) and a 60 % TOC reduction in 3 h reaction time at 80 ºC and the theoretical stoichiometric amount of H 2 O 2 (530 mg L -1 ).The ecotoxicity of the effluent was negligible and the biodegradability was highly improved. In a long-term experiment (100 h), the catalyst suffered a loss of activity upon the early stages on stream (≈15 h), where about 20% of Fe was lost, followed by a highly stable behavior for the rest of the experiment.

Magnetic titanium/carbon nanotube nanocomposite catalyst for oxidative degradation of Bisphenol A from high saline polycarbonate plant effluent using catalytic wet peroxide oxidation

“…In the next step, as described by Eq. (14), H 2 CO 3 decomposed into water and carbon dioxide (then CO 2 goes to gas phase) [21,56,57]. Therefore, it expected that the performance of CWPO at pH < 6.35 will favour the degradation of BPA present in PCW, in order to overcome the interference of bicarbonate species (10345 mg/L).…”

“…for decomposition of recalcitrant compounds. The advantages of AOPs can be summarized to the simplicity of the required equipment, the operation at mild conditions and the capability to degrade a wide range of organic pollutants to the extent of mineralization [11][12][13][14][15][16][17]. In this sense, catalytic wet peroxide oxidation (CWPO) is an AOP based on the transfer of electrons from an appropriate catalyst to hydrogen peroxide (H 2 O 2 ) molecules in order to accelerate its catalytic decomposition into hydroxide ions (OH − ) and hydroxyl radicals (HO % ) (E 0 = 2.73 V), as given in Eq.…”

“…Therefore, in order to overcome the abovementioned important shortcomings, application of heterogeneous catalysts have important advantages compared to the homogenous catalyst [21,24,25]. Among iron-containing heterogeneous catalysts (such as Fe 3 O 4 , Fe 2 O 3 , Fe 0 and FeOOH), Fe 3 O 4 magnetic nanoparticles (MNPs) are considered one of the most efficient heterogeneous nanocomposites to use in CWPO [14,24]. In a similar mechanism to that shown in Eq.…”

Enhanced degradation of Bisphenol A from high saline polycarbonate plant wastewater using wet air oxidation

“…BPA is generally applied by the manufacturers as an intermediate for the production of several kinds of polymeric materials such as polycarbonate products like baby bottles, epoxy resins, polyacrylates, polyvinyl chloride (PVC) and flame retardants such as tetrabromobisphenol A, among others. (Umar et al, 2013;Kusvuran and Yildirim, 2013;Mena et al, 2017). It is estimated that the world rate of BPA production in 2015 was approximately 5.4 million tones (Mena et al, 2017).…”

“…(Umar et al, 2013;Kusvuran and Yildirim, 2013;Mena et al, 2017). It is estimated that the world rate of BPA production in 2015 was approximately 5.4 million tones (Mena et al, 2017). The removal efficiencies of BPA in wastewater treatment plants (WWTP) were reported to be from 37 to 94% (Liu et al, 2011).…”