Wyniki wyszukiwania - BazTech

1

Wpływ sposobu mineralizacji odcieków składowiskowych zawartość wybranych pierwiastków oznaczanych metodą ICP-OES

Muszyńska Joanna, Gawdzik Jarosław

Gaz, Woda i Technika Sanitarna

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2024

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Nr 3

28--32

PL

W pracy przedstawiono badania zawartości metali ciężkich w odciekach składowiskowych, po mineralizacji na mokro wg dwóch metodyk - metodą referencyjną z wodą królewską (A) oraz dla porównania - metodą mikrofalową (108 kJ/cm3) (B) w mineralizatorze mikrofalowy MW-3000 firmy Perkin Elmer. Celem badań było porównanie wpływu zastosowanej metody mineralizacji na wyniki zawartości metali ciężkich, w próbach odcieków pobranych ze składowiska odpadów komunalnych w Barczy (woj. świętokrzyskie) i poddanych procesowi oczyszczania metodą Fentona.

EN

This paper presents a study of the content of heavy metals in landfill leachates after wet mineralization according to two methodologies - the reference method with royal water (A) and, for comparison, the microwave method (108 kJ/cm3) (B) in a Perkin Elmer MW-3000 microwave mineralizer. The purpose of the study was to compare the effect of the applied mineralization method on the results of heavy metal content in leachate samples taken from the municipal landfill in Barcza (Swietokrzyskie voivodeship) and subjected to Fenton treatment.

2

Wpływ procesu Fentona na wybrane parametry mikrobiologiczne i fizykochemiczne oczyszczanych ścieków z przemysłu drobiarskiego

Makara Agnieszka, Kowalski Zygmunt, Generowicz Agnieszka, Mala Marcin

Przemysł Chemiczny

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2023

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T. 102, nr 9

934--939

PL

Przedstawiono wyniki badań oczyszczania ścieków z przemysłu drobiarskiego metodą pogłębionego utleniania w procesie Fentona. Reakcje Fentona prowadzano przy stałej dawce katalizatora i zmiennych dawkach utleniacza, przy stosunku masowym Fe²+:H₂O₂ w zakresie 1:2-1:10. Zastosowana metoda pozwoliła na znaczne zmniejszenie ogólnej liczby mikroorganizmów oraz wyeliminowanie obecności bakterii z grupy coli i Escherichia coli, enterokoków i pałeczek Salmonella we wszystkich oczyszczanych próbkach ścieków w całym zakresie stosowanych dawek nadtlenku wodoru (4-20 g/L). Parametry fizykochemiczne ścieków, takie jak ChZT, barwa i mętność zostały maksymalnie obniżone o odpowiednio 95%, 98% i 100%.

EN

Wastewater from the poultry industry was treated by advanced oxidn. in the Fenton process. A constant catalyst dose and variable oxidant doses were used, with the Fe²+: H₂O₂ mass ratio in the range of 1:2-1:10. The treatment allowed for a significant redn. in the total no. of microorganisms and eliminated the presence of coli form, Escherichia coli bacteria, enterococci and Salmonella bacilli in all treated wastewater samples, in the entire range of H₂O₂ doses (4-20 g/L). The detd. phys. chem. parameters such as COD, color and turbidity were maximally reduced by 95, 98, and 100% resp.

3

Ocena możliwości zastosowania procesu Fentona do czyszczenia ścieków z myjni samochodowej

Włodyka-Bergier Agnieszka, Bergier Tomasz, Mazur Robert, Kowalewski Zbigniew

Przemysł Chemiczny

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2022

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T. 101, nr 9

704--708

PL

Badania prowadzono na rzeczywistych ściekach, a proces Fentona przeprowadzono w klasycznym układzie (Fe(II)/H₂O₂), jak również w modyfikacji z jonami żelaza(III) (Fe(III)/H₂O₂). Badania prowadzono dla stosunków Fe:H₂O₂ wynoszących 1:1, 1:2, 1:3, 1:5, 1:7 i 1:10. W ścieku surowym oraz w ścieku po procesie Fentona oznaczano ChZT, BZT₅, azot ogólny, fosfor ogólny, barwę, mętność, odczyn oraz przewodność elektryczną właściwą. Stwierdzono, że proces Fentona efektywnie obniża ilość całkowitej i biodegradowalnej materii organicznej, stężenie substancji biogennych, barwę i mętność, a także wpływa na niewielkie obniżenie pH ścieku i podwyższenie przewodności elektrycznej właściwej.

EN

The car wastewater was mixed with H₂O₂ solns. and Fe(II) or Fe(III) salt solns. to carry out the Fenton reaction. Fe:H₂O₂ ratios of 1:1, 1:2, 1:3, 1:5, 1:7 or 1:10 were used. COD, BOD₅, total N, total P, color, turbidity, pH and cond. were tested in the samples of raw sewage and sewage treated with the Fenton process. The process effectively reduced the amt. of total and biodegradable org. matter, the concn. of biogenic substances, color and turbidity, and also slightly decreased pH and increased the cond.

4

Treatment of wastewater from the production of meat and bone meal by the Fenton process and coagulation

Makara Agnieszka, Kowalski Zygmunt, Radomski Piotr, Olczak Piotr

Polish Journal of Chemical Technology

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2022

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Vol. 24, nr 4

51--60

EN

Wastewater from the production of meat and bone meal, due to the high load of organic matter and suspended solids, is a significant problem in the process of its treatment. In this work, we examined the method of treating this wastewater using coagulation with hydrogen peroxide and the Fenton process. Treatment variants included the use of variable Fe2+/H2O2 ratios of 1:5–1:30, variable doses of 3–18.0 g/L H2O2, and 5–10 mL/L of coagulant PIX 113. The calculated reduction degrees showed that, regardless of the treatment variant used, the greatest reduction was obtained for turbidity (100%), phosphorus (99%), followed by color (97%), chemical oxygen demand (70%), and Kjeldahl nitrogen (48%). The proposed treatment options can be used as a preliminary stage in treating wastewater from the production of meat and bone meal.

5

Integrated Aerobic-Reagent Technology for the Pre-Treatment of Leachates from Municipal Solid Waste Landfills

Malovanyy Myroslav, Zhuk Volodymyr, Boichyshyn Lidiya, Tymchuk Ivan, Vronska Nataliya, Grechanik Ruslan

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 1

135--141

EN

Accumulation of leachate at municipal solid waste (MSW) landfills is a significant environmental problem. The analysis of known technologies of leachate treatment was performed. It was established that it is not effective to use the same technology to treat leachate in two different periods: before the landfill closure and reclamation process as well as afterwards. The application of integrated two-stage aerobic-reagent pre-treatment technology with subsequent full treatment at municipal wastewater treatment plants was proposed for these purposes. The results of laboratory studies of optimal parameters of technology realization for the pre-treatment of Lviv MSW landfill leachate were presented. Recommendations for the practical implementation of the combined two-stage aerobicreagent technology for the landfill leachate pre-treatment were developed.

6

Do we still need a laboratory to study advanced oxidation processes? A review of the modelling of radical reactions used for water treatment

Wacławek Stanisław

Ecological Chemistry and Engineering. S

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2021

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Vol. 28, nr 1

11--28

EN

Environmental pollution due to humankind’s often irresponsible actions has become a serious concern in the last few decades. Numerous contaminants are anthropogenically produced and are being transformed in ecological systems, which creates pollutants with unknown chemical properties and toxicity. Such chemical pathways are usually examined in the laboratory, where hours are often needed to perform proper kinetic experiments and analytical procedures. Due to increased computing power, it becomes easier to use quantum chemistry computation approaches (QCC) for predicting reaction pathways, kinetics, and regioselectivity. This review paper presents QCC for describing the oxidative degradation of contaminants by advanced oxidation processes (AOP, i.e., techniques utilizing •OH for degradation of pollutants). Regioselectivity was discussed based on the Acid Blue 129 compound. Moreover, the forecasting of the mechanism of hydroxyl radical reaction with organic pollutants and the techniques of prediction of degradation kinetics was discussed. The reactions of •OH in various aqueous systems (explicit and implicit solvation) with water matrix constituents were reviewed. For example, possible singlet oxygen formation routes in the AOP systems were proposed. Furthermore, quantum chemical computation was shown to be an excellent tool for solving the controversies present in the field of environmental chemistry, such as the Fenton reaction debate [main species were determined to be: •OH < pH = 2.2 < oxoiron(IV)]. An ongoing discussion on such processes concerning similar reactions, e.g., associated with sulphate radical-based advanced oxidation processes (SR-AOP), could, in the future, be enriched by similar means. It can be concluded that, with the rapid growth of computational power, QCC can replace most of the experimental investigations related to the pollutant’s remediation in the future; at the same time, experiments could be pushed aside for quality assessment only.

7

Zastosowanie procesu Fentona w oczyszczaniu ścieków z przemysłu odlewniczego

Dawczak Paulina, Dudziak Mariusz

Proceedings of ECOpole

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2020

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Vol. 14, No. 1

79--87

PL

Celem pracy była ocena skuteczności procesu Fentona w oczyszczaniu wybranych ścieków z przemysłu odlewniczego, które wstępnie poddano koagulacji. W procesie koagulacji wydzielono ze ścieków zanieczyszczenia występujące zarówno w fazie zawieszonej, jak i koloidalnej. Dobór korzystnego przebiegu procesu Fentona prowadzono pod względem następujących parametrów: pH ścieków, dawki nadtlenku wodoru, stosunku masowego Fe2+/H2O2 oraz czasu procesu. Dobrane parametry procesu Fentona wynosiły odpowiednio: pH ścieków 2,5, dawka nadtlenku wodoru 5,00 g/dm3, stosunek masowy Fe2+/H2O2 = 0,3 oraz czas procesu 120 min. Dla podanych parametrów wykazano wysoką skuteczność procesu Fentona w obniżeniu chemicznego zapotrzebowania tlenu (ChZT) badanych ścieków z przemysłu odlewniczego. W ściekach obniżyło się również stężenie niejonowych substancji powierzchniowo czynnych (NSPC).

EN

The aim of the study was to evaluate the effectiveness of the Fenton process in the treatment of selected wastewater from the foundry industry, which was initially coagulated. In the coagulation process, contaminants found in the suspended and colloidal phase were separated from the wastewater. The selection of the favorable course of the Fenton process was carried out with the following parameters in mind: wastewater pH, hydrogen peroxide dose, Fe2+/H2O2 mass ratio and process time. The selected parameters of the Fenton process were: wastewater pH = 2.5, hydrogen peroxide dose 5.00 g/dm3, Fe2+/H2O2 mass ratio = 0.3 and process time 120 min. For the given parameters, high efficiency of the Fenton process in lowering the chemical oxygen demand (COD) of the treated wastewater from the foundry industry was demonstrated. In wastewater, the concentration of non-ionic surfactants (NSPC) also decreased.

8

Preliminary assessment of the susceptibility of selected animal waste to stabilization in the Fenton process

Janda Anna, Marcinkowski Tadeusz

Environment Protection Engineering

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2020

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Vol. 46, nr 4

5--20

EN

The stabilization of post-slaughter soft animal waste with Fenton’s reagent has been studied. Crude waste was characterized by a high content of fat (581.8 g/kg d.m.) and proteins (264.5 g/kg d.m.), and the share of organic mass constituting 93.6% of d.m. The stabilization was investigated in two reaction variants using various dozes of oxidant (100–1000 cm3/kg/d.m.) and Fe2+:H2O2 molar ratios (1:10, 2:10 and 4:10), for a period of 1 day. During the stabilization, an increase in the solubility of FeSO4·7H2O in waste was observed, probably due to the binding of Fe2+ ions in ferroorganic ligands. The dynamics of the process and the efficiency of the decomposition of organic compounds increased with increased doses of reagents. The biggest loss of organic mass was recorded for the stabilization variant without initial acidification of the reaction environment. The studies confirm the possibility of disregarding the preacidification step of stabilized waste without adversely affecting the oxidation efficiency of organic compounds. A high degree of reduction in protein and fat concentrations with a low organic mass loss are evidence of incomplete oxidation of these compounds.

9

Treatment of wastewater from the foundry industry using Fenton process

Dawczak Paulina, Dudziak Mariusz

Architecture Civil Engineering Environment

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2020

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Vol. 13, no. 1

115--120

EN

The aim of the study was to evaluate the effectiveness of the Fenton process in the treatment of selected wastewater from the foundry industry, which was initially coagulated. In the coagulation process, contaminants found in the suspended and colloidal phase were separated from the wastewater. The selection of the favorable course of the Fenton process was carried out with the following parameters in mind: wastewater pH, hydrogen peroxide dose, Fe2+/H2O2mass ratio and process time. The selected parameters of the Fenton process were: wastewater pH 2.5, hydrogen peroxide dose 5.00 g/L, Fe2+/H2O2 mass ratio 0.3 and process time 120 min. For the given parameters, high efficiency of the Fenton process in lowering the chemical oxygen demand (COD) of the treated wastewater from the foundry industry was demonstrated. In wastewater, the concentration of non-ionic surfactants (NS) also decreased.

10

Metody usuwania trwałych zanieczyszczeń organicznych z osadów dennych

Kida Małgorzata, Ziembowicz Sabina, Koszelnik Piotr

Instal

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2019

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nr 6

49--55

PL

Praca zawiera przegląd literatury na temat metod usuwania zanieczyszczeń organicznych z wydobytych osadów dennych. Wśród tych technologii wyróżnia się metody fizyczne, chemiczne, termiczne, biologiczne oraz łączone. Do oczyszczania wydobytych osadów dennych najczęściej stosuje się metody biologiczne. Wymagają one jednak długiego czasu prowadzenia procesu i często toksyczność usuwanych substancji oraz ich ubocznych produktów rozkładu przyczynia się do zahamowania biodegradacji. W tym celu należy poszukiwać nowych, lepszych rozwiązań. W ostatnich latach coraz bardziej popularne są procesy z wykorzystaniem pola ultradźwiękowego oraz odczynnika Fentona, które wpisują się w zasady zielonej chemii. Ponadto metody te można prowadzić w układach łączonych, które zazwyczaj pozwalają na uzyskanie wyższego stopnia degradacji zanieczyszczeń organicznych w porównaniu z procesami pojedynczymi.

EN

The work contains a review of the literature on the methods of removing organic pollutants from dredged bottom sediments. These technologies include physical, chemical, thermal, biological and combined methods. The biological methods are most often used for the treatment of dredged bottom sediments. However, they require a long process time and often the toxicity of the removed substances and their by-products of decomposition contributes to the inhibition of biodegradation. For this purpose, new and better solutions are sought. In recent years, processes using the ultrasonic field and the Fenton reagent, which are part of the principles of green chemistry, are becoming more and more popular. In addition, these methods can be carried out in combined systems, which usually allow a higher degree of degradation of organic contaminants compared to single processes.

11

Application of Fenton Reaction and Nanofiltration for the Recovery of Process Water

Żyłła Renata, Kos Lech

Fibres & Textiles in Eastern Europe

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2019

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Vol. 27, no. 2 (134)

101--106

EN

In this study, the Fenton process and nanofiltration were used to purify wastewater from dyeing with reactive dyes. Ferrous sulfate doses ranging from 100 to 1000 mg/dm3 and hydrogen peroxide doses ranging from 2.5 to 10 cm3/dm3were applied. It was found that in the whole range of ferrous sulfate doses, the degree of decolorisation was very high, reaching 97-99%. Consequently the wastewater from the Fenton process was practically completely decolorised. In the case of COD, with increasing doses of ferrous sulfate, the reduction rate initially increased from 25 to 38% and then decreased to 28%. An increase in the hydrogen peroxide dose resulted in a rise in COD reduction to about 50%. It was found that application of the Fenton reaction before the nanofiltration process improved filtration parameters. A clear reduction in the fouling effect of the membrane in the integrated wastewater treatment process was reported as compared to nanofiltration alone.

PL

W pracy zastosowano proces Fentona i nanofiltrację do oczyszczania ścieków pochodzących z procesów barwienia barwnikami reaktywnymi. Stosowano dawki siarczanu żelazawego w zakresie od 100 do 1000 mg/dm3 i dawki nadtlenku wodoru w zakresie od 2,5 do 10 cm3/dm3. Stwierdzono, że w całym zakresie stosowanych dawek siarczanu żelazawego uzyskany stopień odbarwienia ścieków był bardzo wysoki rzędu 97-99%. Tak więc ścieki po procesie Fentona były praktycznie całkowicie odbarwione. W przypadku ChZT wraz ze zwiększaniem stosowanej dawki siarczanu żelazawego stopień redukcji początkowo wzrósł z 25 do 38%, a następnie obniżył się do poziomu 28%. Zwiększając dawkę nadtlenku wodoru uzyskano wzrost stopnia redukcji ChZT do około 50%. Stwierdzono, że zastosowanie procesu Fentona przed procesem nanofiltracji pozwoliło na poprawę parametrów filtracji. Odnotowano wyraźne zmniejszenie „efektu foulingu” membrany w zintegrowanym procesie oczyszczania ścieków, w porównaniu z samą nanofiltracją.

12

Evaluation of influence of coagulation/flocculation and Fenton oxidation with iron on landfill leachate treatment

Smaoui Yosr, Mseddi Salma, Ayadi Najla, Sayadi Sami, Bouzid Jalel

Environment Protection Engineering

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2019

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Vol. 45, nr 1

139--153

EN

Landfill leachates (LFL) collected from Sfax (Tunisia) discharge area are characterized by high chemical oxygen demand (COD), ammonium and salts contents. They constitute a source of phytotoxicity and pollution for ground water and surface water resources which requires an adequate treatment process. To evaluate the efficiency of the coagulation/flocculation treatment, special attention was paid to the effect of pH, coagulant and flocculant doses. Then, effect of zero valent iron was also studied alone and in combination with coagulation/flocculation pretreatment. Our results indicate high removal efficiencies by coagulation/flocculation (46% COD and 63% turbidity) and Fenton process (48% COD and 76% turbidity). The combined application of coagulation/flocculation and Fenton revealed higher COD removal (62%) and turbidity reduction (90%). These results showed the applicability of this combined treatment method for the degradation of organic compounds and reduction of the treated leachate toxicity.

13

Study of catalytic processes for biodiesel production wastewater treatment

Borralho Teresa, Coelho Solange, Estrelo Andreia

Archives of Environmental Protection

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2019

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Vol. 45, no. 2

66--72

EN

The study of the possibility of removing organic compounds from wastewater originating from the biodiesel purification stage by two catalytic processes, HSO5-/transition metal and Fenton method has been presented. The source of the ion HSO5-is potassium monopersulphate (2KHSO5∙KHSO4∙K5SO4) (Oxone) that may be decomposed into radicals (OH., SO4-., SO5-.) by means of transition metal as Co(II). Different concentrations were used for both compounds and the combination ([Co2+] = 1.00μM/[HSO5-] = 5.00·10-2 M) achieved the highest COD removal (60%) and complete decomposition of the oxidant was verified for contact times of 45 min. This process has some advantages comparing to the conventional Fenton method such as the absence of the costly pH adjustment and the Fe(III) hydroxide sludge which characterize this treatment process. The Fenton process showed that the combination of [H2O2] = 2.00M/[Fe2+] = 0.70 M was the best and archived COD removal of 80%. The treatments studied in this research have achieved high COD removal, but the wastewater from the biodiesel purification stage presents very high parametric values of Chemical Oxygen Demand (667,000 mgO2/L), so the final COD concentration reached is still above the emission limit of discharge in surface water, according the Portuguese Law (Decree-Law 236/98). However, both treatments have proved to be feasible techniques for the pre-oxidation of the wastewater under study and can be considered as a suitable pre-treatment for this type of wastewaters. A rough economic analysis of both processes was, also, made.

14

Wpływ relacji Fe:H2O2 na skład odcieków składowiskowych po oczyszczaniu metodą Fentona

Muszyńska J., Gawdzik J., Sikorski M.

Proceedings of ECOpole

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2018

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Vol. 12, No. 1

211--217

PL

W wyniku funkcjonowania składowisk odpadów powstają odcieki, które są odzwierciedleniem zmian zachodzących w czaszy składowiska. Na początku funkcjonowania składowiska powstają odcieki zawierające głównie produkty podatne na biodegradację, wraz z upływem czasu rośnie ilość związków trudno biodegradowalnych. Ze względu na zmienność składu i ilości powstających odcieków ich oczyszczanie jest trudnym zadaniem technologicznym i wymaga szeregu badań. Do oczyszczania odcieków stosowane są zarówno metody biologiczne, fizyczno-chemiczne, jak i metody pogłębionego utleniania, np. metoda Fentona. W artykule przedstawiono problematykę dotyczącą wpływu relacji Fe:H2O2 w procesie Fentona na skład oczyszczonych odcieków i redukcję wybranych zanieczyszczeń. Omówiono parametry fizyczno-chemiczne odcieków surowych oraz po procesie oczyszczania metodą Fentona. Celem badań, oprócz wykonania analiz chemicznych, było również określenie zależności pomiędzy stosunkiem Fe:H2O2 a efektem obniżenia wartości wybranych wskaźników zanieczyszczeń. Wyniki analiz odniesiono do dopuszczalnych zakresów stężeń wybranych substancji zamieszczonych w rozporządzeniach krajowych. Proces Fentona prowadzono przy stosunku wagowym Fe:H2O2 jak 1:3, 1:5, 1:7, 1:10 przy dawce Fe co 50 g/m3 w zakresie od 50-400 g/m3. W odciekach surowych i oczyszczonych analizowano zawartość takich parametrów, jak ChZT, OWO, UV254, barwa. Na podstawie wyników badań wybrano optymalną relację Fe:H2O2. Wyjaśniono możliwe przyczyny niskiej skuteczności wysokich dawek Fe przy relacji Fe/H2O2 1:10.

EN

As a result of the storage of waste, generation of leachate reflect changes in the canopy landfill. At the beginning of landfill operation, the landfill leachate arise mainly products biodegradable, over time, increasing the number of non-biodegradable compounds. Due to the variability of the composition and quantity of leachate generated their cleaning is difficult and requires a number of technological research. For leachate treatment they are used both methods of biological and physico-chemical methods such as advanced oxidation e.g. Fenton’s method. The article presents the problem of the impact of the relationship between Fe/H2O2 ratio of process Fenton on the composition of treated effluent and a reduction of selected pollutants. The physico-chemical parameters of raw leachate and after the process of purification by Fenton have been discussed. The aim of the research, in addition to performing chemical analyses, was also to determine the relationship between the ratio Fe:H2O2 and the reduction of selected pollutants. The results of analyses related to the limit values given in national regulations. Fenton process was carried out at a weight of Fe: H2O2 ratio: 1: 3, 1: 5, 1: 7, 1:10 Fe at a dose of 50 g/m3 in the range of 50-400 g/m3. The leachate raw and analysed the contents of parameters such as COD, TOC, UV254, colour. Based on the results of research we selected the optimal ratio of Fe:H2O2. The possible causes of low effectiveness of high doses of Fe for the ratio Fe:H2O2 1:10 was explained.

15

Degradation mechanism study of amine collectors in Fenton process by quantitative structure-activity relationship analysis

Wang X., Liu W., Duan H., Liu W.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 3

713--721

EN

In this study, advanced oxidation processes (AOPs), Fenton process, was applied to degrade ten amine collectors. The experimental results indicated that most of the tested amines could be removed rapidly and effectively at pH=4, while the degradation of quaternary ammonium compounds was less than others. To research the Fenton oxidation process, the degradation-rate constants of amine collectors were calculated by the pseudo-second order kinetic model, then which was used as the dependent variable to establish a quantitative structure activity relationship (QSAR) model. Meanwhile, 16 molecular structure descriptors and quantum mechanical parameters for amine collectors were simulated and analyzed by using Materials Studio software. The optimum QSAR model was established based on the partial least squares regression (PLS) method and confirmed by the statistics analysis. The model revealed that hydrogen bond acceptor (HBA) and the maximum values of electrophilic attack in C atom sites (f(-)c) were the major effect factors for the degradation-rate constants of amine collector.

16

Treatment of the pistachio processing wastewater using Fenton’s, ultrasound with Fenton’s, and coagulation processes

Demir O., Rastgeldi B.

Environment Protection Engineering

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2018

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Vol. 44, nr 1

167--180

EN

Pistachio processing wastewater was characterized and the treatability of wastewater using Fenton’s process, the combination of Fenton’s process with ultrasonic irradiation and coagulation processes was investigated. [Fe2+] = 27.6 mg/dm3, [H2O,sub>2]= 30 mg/dm3 and 75 min of reaction time were determined as the optimum conditions for Fenton’s process. Then, the combined treatment (ultrasound with Fenton’s process, was applied to the pistachio processing wastewater and 45% of COD removal efficiency was obtained. For the coagulation process, the optimum removal efficiencies of 60% and 45% were achieved for FeCl3 dosage of 2000 mg/dm3 and Al2(SO4)3 dosage of 3000 mg/dm3, respectively. The results demonstrate that higher COD removal efficiencies could be obtained from the combined ultrasound and Fenton’s process with respect to Fenton’s process alone. Besides, applying the coagulation process using FeCl3and Al2(SO4)3 also presents high COD removal efficiencies.

17

Photocatalytic efficiencies of alternate heterogeneous catalysts: Iron modified minerals and semiconductors for removal of an azo dye from solutions

Yatmaz H. C., Sen U. D. K.

Environment Protection Engineering

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2018

|

Vol. 44, nr 1

5--17

EN

Photocatalytic degradation of reactive dye solutions have been compared using two types of heterogeneous catalysts, i.e., semiconductors and iron modified clays. Decolorization and mineralization efficiencies of the catalysts were performed in a slurry batch reactor with UVA and UVC (365 and 254 nm, respectively) light sources using reactive azo dye solutions. Two natural minerals (zeolites and beidellites) modified with Fe3+, Fe2+and semiconductors (TiO2-P25 and ZnO) were used as photocatalysts. Iron modified minerals produced similar results compared to homogeneous photo-Fenton reactions under UVC radiation. Fe2+-beidellite and Fe3+-zeolite showed the best efficiency for dye removal with 98.5% at 75 min and 96.3% at 90 min, respectively, which is higher than the other iron modified minerals under UVA radiation. ZnO and TiO2 exhibited initial dye removal rates under UVA as 98.9% and 95.5% at 45 min, respectively. Mineralization efficiencies for TiO2, ZnO and Fe2+-beidellite, Fe3+ -zeolite under UVA were 86.2%, 74.5% and 76.9%, 67.8%, respectively. However mineral catalysts performed 99% dye removal rates within 15 min with respect to semiconductor catalyst values (over 97% within 45min) under UVC radiation. Mineral catalysts and TiO2 provided higher initial TOC removal rates as 92% in 60 min under UVC radiation.

18

Oczyszczanie ścieków przemysłowych zawierających formaldehyd z wykorzystaniem procesu Fentona

Kowalik P., Naumczyk J., Bogacki J., Marcinowski P.

Gaz, Woda i Technika Sanitarna

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2017

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Nr 5

234--237

PL

Próbki ścieków zawierających formaldehyd: z produkcji płyt wiórowych (A) i ścieki ogólnozakładowe (B) pobrane z zakładu produkcji płyt wiórowych poddano oczyszczaniu z wykorzystaniem procesu Fentona. Ścieki znacznie różniły się między sobą zawartością formaldehydu (0.1-2108 mg/1) i wartością ChZT (2025-9288 mg/1). W wyniku zastosowania procesu Fentona uzyskano znaczne zmniejszenie zawartości formaldehydu. Dla ścieków (A) osiągnięto maksymalnie 68.6% jego usunięcia, do wartości 661 mg/l. Skuteczność procesu wyliczona na podstawie zmniejszenia wartości ChZT była mniejsza niż w przypadku usunięcia formaldehydu. Największą skuteczność usunięcia ChZT, 94.9%, osiągnięto dla ścieków ogólnozakładowych (B). W przypadku ścieków A, uzyskano bardzo wysoki, dochodzący do 68.0% usunięcia ChZT, do wartości 2973 mg/1.

EN

Formaldehyde containing wastewater: chipboard production (A) and general-purpose (B) were collected from the chipboard production plant and subjected to the Fenton process treatment. The concentrations of formaldehyde (0.1 2108 mg/1) and COD (2025-9288 mg/1) varied considerably between the samples. As a result of the Fenton process, a significant formaldehyde removal was achieved. For wastewater (A), 68.6% removal was reached, up to 661 mg/1. The effectiveness of the process, calculated on the basis of COD removal was lower than in case of formaldehyde removal. The highest COD removal efficiency, 94.9%, was achieved for general-purpose wastewater (B). For wastewater (A), a very high, up to 68.0% COD removal was obtained, up to 2973 mg/1.

19

Degradation of p-aminophenol by Fenton’s process. Influence of operational parameters

Ghosh P., Ghime D., Lunia D.

Environment Protection Engineering

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2017

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Vol. 43, nr 3

255--267

EN

Oxidative degradation of a model environmental pollutant, p-Aminophenol (PAP), in aqueous solution has been investigated in an environmentally friendly advanced oxidation Fenton process. Effects of various operating parameters such as pH of solutions, dosage of hydrogen peroxide and ferrous ions, initial PAP concentration and temperature on the degradation of PAP have been studied using a batch stirred ceil. Degradation kinetics for this pollutant was also investigated to determine the apparent rate constants (min-1)- The optimum conditions for the degradation of PAP solution (200-500 mg/dm3) were found to be pH = 3.0, 2400 mg H2O2dm, 300 mg Fe2+/dm3, 30°C. Under the optimum conditions, the degradation efficiency of PAP was 75% after 50 min of reaction. It was observed that process parameters play a major role in the overall degradation process.

20

Advanced oxidation treatment of pentoxifylline in aqueous solutions

Kamińska B., Skwierawska A., Kozłowska-Tylingo K., Tomczak-Wandzel R., Pazik A., Majewska K.

Environment Protection Engineering

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2017

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Vol. 43, nr 1

31--47

EN

The degradation of pentoxifylline (PTX) using H2O2, UV, H2O2/UV, Fenton and photo-Fenton processes has been examined in aqueous solutions. The influence of oxidation agent and initial PTX concentration, on H2O2, H2O2/UV, Fenton and photo-Fenton reactions was investigated. The addition of inorganic ions (Cl–, NO3–, SO42– and CO32–) on the degradation efficiency of PTX was tested for H2O2/UV, Fenton and photo-Fenton processeses. The results indicate that the photo-Fenton reaction is the most sufficient for PTX removal. The complete pharmaceutics decomposition is achieved after 5 min under optimized concentration of FeSO4,·7 H2O2 and H2O2. The degradation of PTX is inhibited in the presence of inorganic matter in H2O2/UV and Fenton reaction. In the photo-Fenton process addition of above compounds does not affect the reaction rate. Structures of ten products of photo-Fenton reaction have been proposed.