Decomposition Of Peracetic Acid Research Articles

Peracetic acid pretreatment improves biogas production from anaerobic digestion of sewage sludge by promoting organic matter release, conversion and affecting microbial community

Peracetic acid (PAA) pretreatment is considered as a novel and effective chemical pretreatment method for sludge. However, there is little information available on potential mechanisms of how PAA pretreatment affects sludge anaerobic digestion (AD). To fill the knowledge gap, this study investigated the effects and potential mechanisms of PAA pretreatment on sludge AD systems from physicochemical and microbiological perspectives. Batch experiments resulted that biogas production was enhanced by PAA pretreatment and the highest cumulative biogas yield (297.94 mL/g VS (volatile solid)) was obtained with 2 mM/g VS of PAA pretreatment. Kinetic model analysis illustrated that the PAA pretreatment improved the biogas potential (Pt) of sludge AD, but prolonged the lag phase (λ) of AD. Mechanistic studies revealed that reactive oxygen species (ROS) (HO•, O2−•, 1O2 and CH3C(O)OO•) were the major intermediate products of PAA decomposition. These ROS effectively promoted the decomposition and solubilization of sludge, and provided more biodegradable organic matter for the following AD reactions. 16S rRNA amplicon sequencing showed that some functional microorganisms associated with hydrolysis, acidogenesis, acetogenesis as well as methanogenesis, such as Hydrogenispora, Romboutsia, Longivirga, Methanosarcina and Methanosaet, were significantly enriched in reactors pretreated with PAA. Redundancy analysis and variation partitioning analysis indicated that functional microorganisms were significantly correlated with intermediate metabolites (soluble carbohydrate, soluble protein, soluble chemical oxygen demand and volatile fatty acids) and cumulative biogas production. This study provides a fresh understanding of the effects and mechanisms of PAA pretreatment on sludge AD, updates the insights into the response of functional microorganisms to PAA pretreatment, and the findings obtained might provide a fundamental basis for chemical pretreatment of sludge AD using oxidants.

Biochar loaded with CoFe2O4 enhances the formation of high-valent Fe(IV) and Co(IV) and oxygen vacancy in the peracetic acid activation system for enhanced antibiotic degradation

Corn straw and sludge-derived biochar composite (BC) loaded with CoFe2O4 was successfully prepared to activate peracetic acid (PAA) for efficient degradation of tetracycline hydrochloride (TCH). Within 60 s, 96 % TCH removal efficiency was achieved through a non-free radical degradation pathway, primarily driven by singlet oxygen (1O2). The mechanism involves the electron-rich groups on the biochar surface, which facilitate the cleavage of the PAA OO bond to generate •O2−/1O2 and provide electrons to induce the formation of high-valent Fe(IV) and Co(IV). The oxygen vacancies on the surface of the CoFe2O4-loaded biochar composite (CFB-2) contribute partially to 1O2 production through their transformation into a metastable intermediate with dissolved oxygen. Moreover, elevated temperatures further enhance PAA activation by CFB-2, leading to increased reactive oxygen species (ROS) production through PAA decomposition, thereby promoting TCH removal. This study offers new insights into the catalysis of metal-loaded biochar for efficient TCH degradation via non-free radical generation.

FeCu-coal gangue heterogeneous activation of peracetic acid for degradation of sulfamethoxazole

A novel FeCu anchored coal gangue (FeCu-CG) composite was prepared by a two-step (acidation and subsequent chemical reduction) method and applied in catalytic activation of peracetic acid (PAA) for sulfamethoxazole (SMX) removal in water. The BET, XPS, SEM, EDS, and XRD characterization of FeCu-CG indicated that it had a porous structure with the SBET area of 36.38 m² g−1 and nano-FeCu particles were successfully loaded in the CG carrier, which provided electrons and Fe(II) for PAA decomposition through the bimetallic corrosion reaction. The hydroxyl radical (HO•) was verified to be largely responsible for SMX elimination in FeCu-CG/PAA system. More than 96.4 % of SMX was removed by FeCu-CG/PAA in 40 min at initial pH ranging from 5.0 to 9.0. Increasing FeCu-CG dosage from 0.1 to 1.0 g L−1 could enhance SMX degradation in FeCu-CG/PAA system, but higher dosage inhibited SMX removal owing to the aggregation of FeCu-CG particles. Coexisting dissolved organic matter (DOM), HCO3- and Cl- suppressed SMX degradation. The degradation pathways of SMX by FeCu-CG/PAA were proffered including hydroxylation, amino oxidation, bond cleavage and coupling reaction based on five detected degradation products.

Activation of peracetic acid with zero-valent iron for tetracycline abatement: The role of Fe(II) complexation with tetracycline

Peracetic acid (PAA) is an excellent oxidant that can produce multiple carbon-centered radicals (R•C). A novel advanced oxidation process (AOP) that combines PAA and nanoscale zero-valent iron (i.e. nZVI/PAA) is constructed to evaluate its performance toward tetracycline (TC) abatement. The nZVI/PAA process shows excellent abatement efficacy for TC in the pH range of 3.5–7.5. The presence of humic acid, HPO42− and HCO3− exerts inhibitory effects on TC abatement, while the presence of Cl− displays negligible influence in the nZVI/PAA process. Nanoscale zero-valent iron (nZVI) exhibits excellent reusability with no apparent variation in crystallinity. CH3C(O)OO• is the predominant active radical that contributes to TC abatement, in which leakage of Fe(II) from the nZVI surface is crucial for a radical generation. Due to the strong complexation tendency of TC towards Fe(II), the Fe(II)-TC complexes are formed, which significantly accelerates the PAA decomposition and TC abatement compared to free Fe(II). In addition, the degradation intermediates of TC are identified, and a possible degradation pathway is proposed. These results will be useful for the application of PAA-based AOPs in the treatment of water containing organic micropollutants.

Sustainable recovery of wastewater to be reused in cooling towers: Towards circular economy approach

Circular economy approach is needed in order to move towards sustainable development. In this frame, the current work is aimed at improving the sustainability of a food industrial plant through circular economy approach, using a waste stream, coming from the washing and disinfection of bottles before product packaging, as source of water for the cooling process. The implementation of this approach is much more relevant in sectors that are water-intensive, such as food and beverages industry. The wastewater produced as results of the washing process has quite high quality, therefore, there reuse in the cooling process is justified. However, it is needed to previously remove the hydrogen peroxide present in that wastewater stream to protect refrigeration circuits from oxidation. Hydrogen peroxide is produced as a result of the decomposition of peracetic acid, which is used as disinfection agent in the washing process, being acetic acid the other byproduct. In order to remove the hydrogen peroxide, catalytic decomposition of hydrogen peroxide with activated carbon was performed, studying both required contact time for different activated carbon/hydrogen peroxide ratios and kinetic models of hydrogen peroxide decomposition at lab scale. Subsequently, the proposed solution was applied at industrial scale, achieving 100 % water replacement in cooling towers. The solution performed in this case can be easily replicated in other plants using peracetic acid as disinfectant.

Interactions between peracetic acid and TiO2 nanoparticle in wastewater disinfection: Mechanisms and implications

While peracetic acid (PAA) are known to be susceptible to decomposition by metals for radical generation, herein we report a novel decomposition process of PAA with TiO2 nanoparticle (nTiO2) for the first time. nTiO2 in anatase (A_nTiO2) could significantly enhance the decomposition of PAA, whereas, nTiO2 in rutile phase had no impact on the stability of PAA. Electron paramagnetic resonance (EPR) technique and a radical quenching study indicated lack of involvement of reactive radicals. In-depth investigation revealed that the {001} facets of A_nTiO2 with high surface free energy were especially reactive for the catalytic decomposition of PAA. Theoretical calculations proved the adsorption of PAA onto A_nTiO2 {001} surface was much more favorable than the predominated {101} facets. The unsaturated five coordinated Ti (Ti5c), typical Lewis acid sites on A_nTiO2 {001} surface, were further confirmed as the dominant active sites for catalyzing PAA decomposition. This novel decomposition process could enhance the stability and migration of A_nTiO2, increasing the potential environmental risk. Meanwhile, the disinfection of PAA was inhibited by introducing A_nTiO2. The new findings of this study broaden the knowledge on PAA decomposition process, and have an important implication for PAA disinfection and environmental behavior of TiO2 nanoparticle.

Thermal Activation of Peracetic Acid in Aquatic Solution: The Mechanism and Application to Degrade Sulfamethoxazole

Chemical oxidation using peracetic acid (PAA) can be enhanced by activation with the formation of reactive species such as organic radicals (R-O•) and HO•. Thermal activation is an alternative way for PAA activation, which was first applied to degrade micropollutants in this study. PAA is easily decomposed by heat via both radical and nonradical pathways. Our experimental results suggest that a series of reactive species including R-O•, HO•, and 1O2 can be produced through the thermal decomposition of PAA. Sulfamethoxazole (SMX), a typical sulfa drug, can be effectively removed by the thermoactivated PAA process under conditions of neutral pH. R-O• including CH3C(O)O• and CH3C(O)OO• has been shown to play a primary role in the degradation of SMX followed by direct PAA oxidation in the thermoactivated PAA process. Both higher temperature (60 °C) and higher PAA dose benefit SMX degradation, while coexisting H2O2 inhibits SMX degradation in the thermoactivated PAA process. With a variation of solution pH, conditions near a neutral value show the best performance of this process in SMX degradation. Based on the identified intermediates, transformation of SMX was proposed to undergo oxidation of the amine group and oxidative coupling reactions. This study definitively illustrates the PAA decomposition pathways at high temperature in aquatic solution and addresses the possibility of the thermoactivated PAA process for contaminant destruction, demonstrating this process to be a feasible advanced oxidation process.

Wastewater disinfection: long-term laboratory and full-scale studies on performic acid in comparison with peracetic acid and chlorine

Chemical disinfection of municipal wastewater to preserve the microbiological quality of discharges has traditionally relied on chlorine, and more recently on peracetic acid (PAA). A more recent option is performic acid (PFA). This work uses laboratory and full-scale studies over a span of 15 years and five wastewater treatment plants (WWTPs) in Italy, to compare the efficacy of these three disinfectants and identify the differences among peracids in a context where both can be an alternative to chlorine. The investigations focused on treatment effectiveness and bacterial inactivation kinetics using E. coli and the more resistant enterococci, as well as on PFA and PAA decomposition as the residuals may affect the downstream microenvironment. Furthermore, the potential for the two peracids to oxidize organic substances and create troublesome byproducts was also studied. Chlorine, applied as hypochlorite (“HYP”) and here essentially functioning as chloramines, was used as a baseline comparison for the two peracids. Appropriate statistical tests were applied to the data from different WWTPs to account for potential interferences and compounding effects of the different matrices. Average doses of 0.8, 2.9 and 1.4 mg/L and contact times of 18, 21 and 31 min, respectively for PFA, chlorine and PAA guaranteed with a high level of assurance the 5000 CFU/100 mL E. coli limit; the order of effectiveness was PFA > HYP > PAA, refined as PFA > HYP ≈ PAA against E. coli and PFA ≈ HYP > PAA with enterococci. Similar bacterial reductions for the peracids were found at higher disinfectant doses used for the kinetic tests. PFA decayed more quickly than PAA. The first-order decay constants were 0.031 and 0.007 min−1, respectively, suggesting that disinfection residuals when PFA is used may be less of a concern than with PAA. This faster decomposition did not affect the PFA oxidation power on estrone, which was as weak as that of PAA.

Optimising the measurement of peracetic acid to assess its degradation during drinking water disinfection.

Chlorine-based compounds have been used as a disinfectant in drinking water treatment plants for decades because of their excellent sterilisation efficiency and low cost. However, the formation of disinfection by-products during chlorination is a cause for concern. Peracetic acid (PAA) is a strong oxidant with a redox potential higher than that of chlorine and does not form harmful disinfection by-products. It is thus a potential alternative for chlorine-based disinfectants. However, PAA decomposes rapidly in water at a rate that is highly affected by many factors, such as organic compounds and pH. The aim of this study is to investigate the stability of PAA during drinking water disinfection. To accomplish this, we studied methods for rapid detection of residual PAA and PAA decay in drinking water. Residual PAA was detected in water by the spectrophotometry-total chlorine reagent (SPTCR) method with a PAA concentration range of 0.090-10 mg/L (R2 = 0.9943). Decay tests of PAA in drinking water and other sources of water showed that the decay process conformed to the first-order kinetic model with fast and slow reactions. Among four factors, pH was the key factor in the decay process because an alkaline environment significantly promotes the decomposition of PAA. In addition, total organic carbon (TOC), conductivity, and initial PAA concentration also affected PAA decay. Experimental and statistical analyses suggested that these factors affected PAA decay in the following descending order of influence: TOC, initial PAA concentration, and conductivity. In real water matrices, the PAA decay rate increased with increasing initial PAA concentration.

Aerosol disinfection of bacterial spores by peracetic acid on antibacterial surfaces and other technical materials

The effectiveness of aerosol disinfection processes based on peracetic acid (PAA) might differ depending on the surface targeted. Especially antibacterial, oligodynamic materials have to be regarded as they could cause elevated decomposition of PAA. This study aimed on the determination of differences in disinfection effectiveness using PAA caused by the treated material. Aerosol disinfection of Geobacillus stearothermophilus spores was performed on the antibacterial, oligodynamic materials copper and brass in comparison to stainless steel and aluminium as well as polyvinylchloride, wood, and ceramics. Additionally, the influence of the materials on the decomposition reaction of PAA was evaluated. For aluminium and stainless steel as well as ceramics and polyvinylchloride, a disinfection of 106 spores of Geobacillus stearothermophilus on 40 cm² was obtained by the employment of 60 mL aerosolized disinfectant/m³ on laboratory scale (0.5 m³). For the application on the oligodynamic materials copper and brass an over 30% higher amount of disinfectant was necessary to achieve significant disinfection results, than for the other material surfaces. In contrast to aluminium and stainless steel, copper and brass caused elevated decomposition of PAA what seems to be the reason for the lowered disinfection effectiveness. Applying aerosol disinfection processes, in addition to parameters such as room size and geometry, the treated materials have to be considered when determining the necessary amount of disinfectant.

Effects of total suspended solids, particle size, and effluent temperature on the kinetics of peracetic acid decomposition in municipal wastewater.

In this study, the influence of total suspended solids (TSS) and particle size as well as effluent temperature on peracetic acid (PAA) decomposition kinetics in municipal wastewater was investigated. PAA decomposition was best described following second order kinetics in primary effluent (PE) and first order kinetics in secondary effluent (SE) samples. For synthetic samples prepared by varying TSS levels, PAA demand increased on average by about 0.042 mg/L in PE and 0.034 mg/L in SE for every 10 mg/L increase in TSS. Similarly, the PAA decay rate constant in these samples increased at a rate of 0.0014 L/mg.min and 0.00039 min-1, respectively, per 10 mg/L TSS. To examine the effect of particle size, synthetic samples with narrow size fractions (20-45, 45-75, and 75-90 μm) were prepared. It was found that samples with smaller particle size fractions had a greater PAA demand and decay rate constant. Effluent temperature also enhanced the PAA decomposition rate with the calculated activation energies for PE and SE samples being 29,980 J/mol and 34,860 J/mol, respectively.

Peracetic acid fate and decomposition in poultry processing wastewater streams

Peracetic acid (PAA) has been increasingly used by the poultry processing industry. However, information related to the potential PAA carryover to and effect on biological treatment processes, commonly used in poultry processing wastewater treatment, is limited. The objectives of this work were to assess the fate of PAA in poultry processing wastewater streams, investigate dominant factors contributing to PAA decomposition, and identify major PAA decomposition products. PAA was detected in chiller overflow and in the dissolved air flotation (DAF) unit influent and effluent only at the end of the processing shift. The PAA decomposition rate correlated positively with pH, temperature, wastewater strength and organic content, and negatively with initial PAA concentration. PAA decomposition followed one-step (pH ≥ 6) or two-step (pH < 6) pseudo-first order kinetics. Decomposed PAA in DAF effluent resulted in equimolar production of acetic acid. A decrease in DAF effluent COD was observed under high PAA doses.

Growth medium sterilization using decomposition of peracetic acid for more cost-efficient production of omega-3 fatty acids by Aurantiochytrium.

Aurantiochytrium can produce significant amounts of omega-3 fatty acids, specifically docosahexaenoic acid and docosapentaenoic acid. Use of a glucose-based medium for heterotrophic growth is needed to achieve a high growth rate and production of abundant lipids. However, heat sterilization for reliable cultivation is not appropriate to heat-sensitive materials and causes a conversion of glucose via browning (Maillard) reactions. Thus, the present study investigated the use of a direct degradation of Peracetic acid (PAA) for omega-3 production by Aurantiochytrium. Polymer-based bioreactor and glucose-containing media were chemically co-sterilized by 0.04% PAA and neutralized through a reaction with ferric ion (III) in HEPES buffer. Mono-cultivation was achieved without the need for washing steps and filtration, thereby avoiding the heat-induced degradation and dehydration of glucose. Use of chemically sterilized and neutralized medium, rather than heat-sterilized medium, led to a twofold faster growth rate and greater productivity of omega-3 fatty acids.

Significant electron transfer in heme catalysis: The case of chlorite dismutase

Electron transfer (ET) is significant in heme catalysis but usually difficult to be characterized. In the present DFT calculations, a transition state for ET has been optimized during the decomposition of peracetic acid (PAA) catalyzed by chlorite dismutase (Cld), using an active-site model based on the X-ray crystal structure of Cld. The Cld-catalyzed PAA reaction is revealed to proceed via a homolytic OO bond cleavage to transiently form compound II (Cpd II) and acetate radical (OAc), and a subsequent fast ET from Cpd II porphyrin to OAc leading to compound I (Cpd I) and acetate anion. The second step of ET is rate-limiting. The results highlight the importance of ET in heme chemistry and imply that the mechanisms of heme enzymes may be masked by fast ET even if a key intermediate has been detected (like Cpd I in this case). The comparison with the Cld-catalyzed chlorite reaction further indicates that a heme enzyme may employ different mechanisms for different substrates.

Asimple method for decomposition of peracetic acid in a microalgal cultivation system.

A cost-efficient process devoid of several washing steps was developed, which is related to direct cultivation following the decomposition of the sterilizer. Peracetic acid (PAA) is known to be an efficient antimicrobial agent due to its high oxidizing potential. Sterilization by 2mM PAA demands at least 1h incubation time for an effective disinfection. Direct degradation of PAA was demonstrated by utilizing components in conventional algal medium. Consequently, ferric ion and pH buffer (HEPES) showed a synergetic effect for the decomposition of PAA within 6h. On the contrary, NaNO3, one of the main components in algal media, inhibits the decomposition of PAA. The improved growth of Chlorella vulgaris and Synechocystis PCC6803 was observed in the prepared BG11 by decomposition of PAA. This process involving sterilization and decomposition of PAA should help cost-efficient management of photobioreactors in a large scale for the production of value-added products and biofuels from microalgal biomass.

INFLUENCE OF TEMPERATURE AND PH ON THE DECOMPOSITION KINETICS OF PERACETIC ACID IN AQUEOUS SOLUTIONS

Peracetic acid (PAA) is a strong oxidant used by the food industry as a sanitizer, in medical area as a disinfectant and by the textiles and paper industries as a bleacher. Its decomposition rate is an important parameter in these applications. The main purpose of this paper is to study the decomposition kinetics of PAA between 25 and 45 °C in solutions with pH 3.11, 5.0 and 7.0. The decomposition of PAA is a first-order reaction for all solutions and temperatures studied. The rate constants were between 2.08·10-3 and 9.44·10-3 h-1 (pH 3.11), between 2.61·10-3 and 16.69·10-3 h-1 (pH 5.0) and between 7.50·10-3 and 47.63·10-3 h-1 (pH 7.0). The activation energy of PAA decomposition in aqueous solutions are 58.36 and 72.89 kJ·mol-1 when pH was 3.11 and 5.0, respectively.

A critical reinvestigation of the TAED-activated peroxide system for low-temperature bleaching of cotton

There exists a misunderstanding on the TAED-activated peroxide system in the textile industry that H2O2 used in excess of the stoichiometric amount could produce an addition effect on bleaching of cotton under alkaline conditions. In this study, a critical reinvestigation was carried out on the TAED-activated peroxide system for bleaching of cotton. It was found that the TAED-activated peroxide system achieved its best performance under near-neutral pH conditions. No addition effect was observed when an excessive amount of H2O2 was used under alkaline conditions, which is probably due to the base-catalyzed bimolecular decomposition of peracetic acid and the nucleophilic attack by H2O2 on peracetic acid. NaHCO3 was shown to be a desired alkaline agent for maintaining near-neutral pH for the TAED-activated peroxide system. This study provides new insight into the application of the TAED-activated peroxide system for low-temperature bleaching of cotton under more environmentally benign conditions.

Preparation of peracetic acid from hydrogen peroxide, part II: Kinetics for spontaneous decomposition of peracetic acid in the liquid phase

A homogeneous kinetic model was developed for describing the synthesis, hydrolysis and spontaneous decomposition of peracetic acid (PAA) in the liquid phase under an acid condition. It was found that the chelant (diethylenetriaminepenta acetic acid, DTPA) was not so effective for reduction of PAA decomposition in a strong acid solution as it in a neutral or alkaline aqueous solution. The expressions for calculating the rate constants of PAA synthesis and hydrolysis obtained in our previous work were still appropriate at a high temperature. The spontaneous decomposition of PAA under an acid condition was an observed second-order reaction with respect to PAA concentration. The observed rate constant was a relatively complicated function of temperature and H + concentration. Addition of sulfuric acid could significantly decrease the PAA decomposition. The reaction mechanism was investigated. It was proved that the rate-determining step for the spontaneous decomposition of PAA was the reaction between PAA molecule and a proton-activated carbonyl intermediary. The application of the kinetic model was further discussed.

Modelling of organic liquid-phase decomposition reactions through gas-phase product analysis: Model systems and peracetic acid

A new method for modelling of liquid-phase decomposition reactions was developed. The method is based on rapid on-line mass spectrometric analysis of liberated products in gas phase. The experimental set-up and the generalized modelling principles were introduced. The approach was demonstrated with first and zero order as well as for complex decomposition kinetics (decomposition of peracetic acid). The interaction of decomposition kinetics and mass-transfer effects was illustrated with theoretical and real reaction conditions. The approach is generally applicable to any liquid-phase decomposition, provided that gaseous products can be quantitatively analyzed.

Mechanism of decomposition of peracetic acid by manganese ions and diethylenetriaminepentaacetic acid (DTPA)

Abstract The decomposition mechanism of peracetic acid by free Mn2+ ions and by Mn2+-diethylenetriaminepentaacetic acid complexes was studied by UV/Vis, electrospray ionization-time of flight-mass spectrometry (ESI-TOF-MS), electron spin resonance (ESR), and Raman spectroscopy. The experimental results demonstrate that a number of different oxidation states of manganese are involved in the decomposition reaction. Furthermore, the kinetics observed show oscillatory features that are characteristic of autocatalytic processes. Radical pathways were found to play a negligible role in the reaction. Based on the experimental observations, an overall reaction scheme for the decomposition process is proposed.