Pentachlorophenol Removal from Water by Soybean Peroxidase and Iron(II) Salts Concerted Action

Abstract

Soybean peroxidase (SBP) has been employed for the treatment of aqueous solutions containing pentachlorophenol (PCP) in the presence of hydrogen peroxide at pH range 5-7. Reaction carried out with 1 mg/L of PCP, 4 mg/L of H2O2 and 1.3 x 10 -9 M of SBP, showed a fast initial elimination of PCP (ca. 30% in 20 min), but the reaction does not go beyond the removal of 50% of the initial concentration of PCP.Modification in SBP and PCP amounts did not change the reaction profile and higher amounts of H2O2 were detrimental for the reaction. Addition of Fe(II) to the system resulted in an acceleration of the process to reach nearly complete PCP removal at pH 5 or 6; this is more probably due to a synergetic effect of the enzymatic process and Fenton reaction. However, experiments developed in tap water resulted in a lower PCP elimination, but this inconvenience can be partly overcome by leaving the tap water overnight in an open vessel before reaction.

A Way to Close the Loop: Physicochemical and Adsorbing Properties of Soybean Hulls Recovered After Soybean Peroxidase Extraction

“…For the extraction of soybean peroxidase (SBP) (Tolardo et al, 2019 ), the seeds were peeled, and the obtained hulls were stored at −12°C until use. SBP was extracted and purified by a process based on a previously published method (Calza et al, 2016 ): 100 g of soybean hulls were ground in a mortar, added to 600 mL of phosphate buffer (0.025 M, pH 7) and left under stirring for 2 h at room temperature.…”

Modeling and simulation of the enzymatic degradation of 2,4,6-trichlorophenol using soybean peroxidase

“…There are several studies of SBP uses for industrial wastewater treatment in the literature, as well as SBP extraction and purification processes [10][11][12][13][14][15][16][17]. Over the years some of the limitations and advancements in the field have been presented, considering aspects such as cost, use of additives for increased enzyme economy, enzyme recycling and studies already completed on industrial wastewaters.…”

“…Furthermore, the degradation products can be identified directly [20,21], since the products usually show different toxicity than the reagents [11]. The most recent study of phenolic compound removal using SBP was in the treatment of aqueous solutions containing pentachlorophenol [17], based on previous studies of TCP degradation [18]. Besides, it was observed that the removal of pentachlorophenol was not complete, maybe because of the interference of intermediates or reaction products.…”

“…Besides, it was observed that the removal of pentachlorophenol was not complete, maybe because of the interference of intermediates or reaction products. In this context, TCP degradation is still one of the most consistent in this area, and further research is needed in order to determine other pollutants for which this approach can be applicable [17].…”

Enzymatic Degradation of 2,4,6-Trichlorophenol in a Microreactor using Soybean Peroxidase

“…Many authors showed the effectiveness of SBP in the oxidation of chlorophenols [14][15][16][17][18]. The ability of SBP in the degradation of 2,4,6-trichlorophenol (TCP) was previously studied by Calza et al [19] using composite material under UV irradiation.…”