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1

Synergizm kompleksów metaloorganicznych z półprzewodnikami do fotokatalitycznego generowania wodoru

Grabowska-Musiał Ewelina

Wiadomości Chemiczne

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2024

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[Z] 78, 3-4

263--278

EN

Currently, considerable attention is paid to durable, stable and energy-saving systems for photocatalytic water decomposition. Traditional photocatalytic systems are mainly based on semiconductor materials surface-modified with noble metals or inorganic cocatalysts. Recently, significant attention has been paid to hybrid systems in which semiconductor materials are integrated with metal complexes, which seem to be an effective strategy for constructing efficient photocatalytic systems for water decomposition. This review focuses on examining the possibility of obtaining photoactive materials by integrating semiconductors with compounds of various metal ions: platinum, nickel and cobalt. The aim of such integration is to increase the efficiency of hydrogen production from water and obtain the so-called "green energy".

2

Kowalencyjne szkielety organiczne : otrzymywanie, właściwości, zastosowanie

Makowski Damian, Bajorowicz Beata

Wiadomości Chemiczne

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2024

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[Z] 78, 3-4

219--241

EN

Covalent organic frameworks (COFs) are a novel and unique crystalline porous organic polymers formed by the reversible condensation of building units containing light elements and linked by strong covalent bonds. Covalent organic frameworks consist of linkers (building units) and chemical bonds formed between two building units. By carefully selecting the appropriate linkers and bonds, it is possible to create covalent organic frameworks with distinct features. This work provides a concise overview of covalent organic frameworks, including their structural, surface, optical, and electronic properties. The preparation strategies most commonly employed for COFs are also presented, along with relevant examples. The potential applications of covalent frameworks in various fields such as: photocatalysis, medicine, gas separation and storage, photovoltaics and sensors are also discussed, highlighting the need for further development of this important class of materials.

3

Kompleksowy przegląd metod preparatyki, właściwości i zastosowań fotokatalitycznych różnych struktur perowskitowych

Miodyńska Magdalena, Cavdar Onur, Pancielejko Anna

Wiadomości Chemiczne

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2024

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[Z] 78, 3-4

243--262

EN

Perovskite materials for photocatalytic environmental and energy conversion applications have drawn excessive attention over recent years owing to their unique photoelectric and catalytic properties. As harvesting solar energy within the bounds of possibility is one of the main aims of photocatalysis, many research groups have devoted their efforts to developing perovskite-based photocatalytic materials from perovskite oxide to metal halide and double halide-based perovskite materials with various synthesis strategies. Particularly, halide and double halide-based perovskites are intriguing thanks to their tunable band gap and band structure depending on the type of halide. Apart from the obstacles related to charge separation and transport processes; instability under water, oxygen, and high temperature hindering their practical photocatalytic application are remaining challenges. Toxicity emerging from Pb2+ or Sn2+ release due to chemical instability is another concern to be tackled. Thusfar, replacing Pb2+ or Sn2+ with Bi3+ is one of the currentscopesin the perovskite photocatalysis area while ensuring chemical stability in halide-based perovskites and thus reducing toxicity. Despite all those challenges, the popularity of perovskite photocatalysis is growing amid the favorable light induced chemical reactions via a plentiful range of promising cost-effective manufacturing methods of perovskites. In this review, the principles and photocatalytic applications of the perovskite oxides, metal halide-based perovskites, and double halide-based are comprehensively discussed.

4

Cząstki typu Janus : otrzymywanie, właściwości i zastosowanie

Gołąbiewska Anna, Głowienke Hanna, Sowik Jakub, Malankowska Anna

Wiadomości Chemiczne

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2024

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[Z] 78, 3-4

279--302

EN

Janus particles are a special class of materials whose uniqueness is based primarily on the lack of central symmetry of the particles, which causes their surfaces to have at least two different physical or chemical properties. Due to their asymmetric structure, Janus-type nanoparticles are used in the fields of chemistry, physics, engineering, and medicine. The work presents three groups of Janus particles: semiconductor-semiconductor, semiconductor-metal and metal-metal, and their methods of preparation and their applications.

5

Efficient and Sustainable Remediation of Refinery Wastewater Using Electrocoagulation and Advanced Oxidation Techniques

Albrazanjy Mohammed G., Hasan Muayad M., Al-Jadir Thaer, Kadhim Wafaa A., Rahim Mohd Hasbi Ab., Al-Rubaiey Najem A.

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 3

197--210

EN

Effluent wastewater from industrial processes needs to be properly treated before being discharged into the environment. Conventional procedures for handling this wastewater can be problematic due to the presence of toxic elements, time constraints, and complexity. However, a new electrochemical procedure has been developed as an effective method for remediation. In a recent study, refinery wastewater was successfully treated using an electrochemical technique combined with ultrasonic irradiation and photocatalysis. The study found that electrocoagulation, which uses cheap and recyclable metal electrodes, was a simple, efficient, practical, and cost-effective way to handle refinery wastewater. Various parameters were investigated, including electrode metals, operating time, applied voltage, pH, inter-electrode gap, and temperature. The aim was to determine the optimal configuration for pollutant removal. The study also focused on the synergistic effects of combining electrocoagulation and photocatalysis to improve the efficiency of contaminant removal in oily wastewater. By integrating these two treatment technologies, the researchers aimed to enhance pollutant removal rates, energy efficiency, and overall system performance. The research provided valuable insights into the feasibility, optimization parameters, and applicability of the electrocoagulation-photocatalysis process for remediating organic contaminants in oily wastewater industrial effluents. The results showed that electrocoagulation, especially when combined with ultrasonic irradiation and TiO2 photocatalysis, was highly effective in pollutant removal within a short timeframe. These findings support the implementation of this procedure for remediating most industrial wastewater.In conclusion, the study contributes to the development of more effective and sustainable water treatment strategies. The electrocoagulation-photocatalysis process shows promise in addressing the remediation of organic contaminants in oily wastewater from industrial processes.

6

Zastosowanie fotokatalizy w syntezie metanolu z metanu

Hamryszak Łukasz, Madej-Lachowska Maria

Przemysł Chemiczny

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2023

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T. 102, nr 12

1308--1320

PL

W pracy przedstawiono podsumowanie postępów badań dotyczących produkcji metanolu z metanu z wykorzystaniem fotokatalizatorów tlenkowych (z udiałem tlenków: wolframu, tytanu, bizmutu, cynku, molibdenu, niklu, ceru oraz galu), a także zeolitów i grafenowych azotków węgla. Omówiono warunki prowadzenia procesu i stosowane dodatki.

EN

A review, with 56 refs., of research progress on the prodn. of MeOH from MeH using oxide photocatalysts: W, Ti, Bi, Zn, Mo, Ni, Ce and Ga, as well as zeolites and graphene C nitrides. The process conditions were presented, in particular the light sources used, the presence/absence of an oxidant and the addn. of the so-called sacrifical reagents, capturing excess electrons in the reaction system. A fundamental scheme of photocatalysis on a semiconductor molecule was presented.

7

Synthesis and Characterization of ZnO/MnFe2O4 Nanocomposites for Degrading Cationic Dyes

Yuniar, Agustina Tuty Emilia, Faizal Muhammad, Hariani Poedji Loekitowati

Journal of Ecological Engineering

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2023

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Vol. 24, nr 4

252--263

EN

By breaking down harmful dye waste into harmless components under the right irradiation sources, photocatalysis is an unorthodox but promising technique that can reduce industrial wastewater pollution, particularly in the textile industry. Synthetic textile dyes called cationic dyes must be handled carefully because they are poisonous and challenging to breakdown. Photocatalytic oxidation is a useful technique for eliminating hazardous organic pigments. This investigation aims to synthesize and characterize ZnO/MnFe2O4 nanocomposites as well as investigate the effects of varying ZnO:MnFe2O4 ratios, pH levels, doses, and irradiation times on band gap reduction and photocatalytic applications tested with cationic dyes, specifically methylene blue, under the illumination of sunlight. the co-precipitation approach for the manufacture of nanocomposites with different mole ratios of ZnO:MnFe2O4 (1:0.1; 2:0.1; 3:0.1). The component comprising the nanocomposite is ZnO/MnFe2O4, according to the results of the characterisation using XRD, SEM-EDX, FTIR, and BET. UV-DRS measurements of the band gap revealed that as ZnO was reduced, the band gap of the nanocomposite likewise decreased, from 3.35 eV to 2.78 eV. The greatest degradation of 93.2% was achieved for the degradation of 50 mg/L methylene blue (MB) dye with a catalyst dosage of 20 mg at a ratio of 1:0.2 for 50 minutes of irradiation. Since the point of zero charges (pzc) was reached at a pH of 7.8, a photodegradation adsorption-friendly solution pH of 8 was created.

8

Electrospun niobium oxide 1D nanostructures and their applications in textile industry wastewater treatment

Zaborowska Marta, Smok Weronika, Tański Tomasz

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 2

art. no. e144941

EN

Textile industry emits daily huge amounts of sewage rich in non-biodegradable organic compounds, especially in textile dyes. Such contaminants are highly soluble in water, which makes their removal difficult. Other studies suggest their carcinogenicity, toxicity and mutagenicity. A promising chemical treatment of textile wastewater is the photodegradation of dye molecules in the process of photocatalysis in the presence of a photocatalyst. One-dimensional nanostructures exhibit a high surface-to-volume ratio and a quantum confinement effect, making them ideal candidates for nanophotocatalyst material. Nb2O5 is, among other metal oxides with a wide band gap, gaining popularity in optical applications, and electrospun niobium oxide nanostructures, despite their ease and low cost, can increase the chemical removal of textile dyes from wastewater. Facile synthesis of electrospun one-dimensional niobium oxide nanofibers is presented. The nanophotocatalysts morphology, structure, chemical bonds and optical properties were examined. Based on photodegradation of aqueous solutions (ph=6) of methylene blue and rhodamine B, the photocatalytic activity was established. The photocatalytic efficiency after 180 minutes of ultraviolet irradiation in the presence of Nb2O5 nanofibers was as follows: 84.9% and 31.8% for methylene blue and rhodamine B decolorization, respectively.

9

Simultaneous photooxidation and photoreduction of phenol and Cr(VI) ions using titania modified with nanosilica

Kądziołka Daria, Grzechulska-Damszel Joanna, Schmidt Beata

Polish Journal of Chemical Technology

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2022

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Vol. 24, nr 4

23--29

EN

The photocatalytic process of phenol oxidation and Cr(VI) reduction in the presence of nano-silica modified titania was carried out. The activity of composites was tested using two different light sources. The photocatalysts with 10% of nanosilica showed the highest activity. The calcination temperature (200–800 °C) significantly determined the sensitivity of the obtained materials to the light source used. Photocatalysts alternately adsorbed and desorbed Cr(VI) ions from the reaction mixture during irradiation. In the one-component mixture, complete oxidation of phenol was observed using material calcined at 650 °C, after 3 h of UV-VIS irradiation. In the reaction mixture of Cr(VI) and phenol, the highest activity was demonstrated by photocatalyst calcined at 300 °C. The concentration of phenol decreased in proportion to the decrease of chromium ions. The obtained titania-silica composites showed oxidizing properties towards phenol and reductive properties toward Cr(VI) ions.

10

Structural and photocatalytic properties of Ni-TiO2 photocatalysts prepared by mechanochemical synthesis assisted with calcination

Kucio Karolina, Charmas Barbara, Zięzio Magdalena, Pasieczna-Patkowska Sylwia

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 4

art. no. 150348

EN

In the study the mechanochemical synthesis in the planetary ball mill was used to prepare photocatalytic materials obtained on the basis of TiO2 and nickel(II) acetylacetonate as a Ni2+ source. Three materials with different contents of Ni2+: 5, 10 and 20% wt. were prepared. The obtained materials were calcinated at 800°C for 1 h. Their physicochemical properties were investigated using the N2 adsorption/desorption, FT-IR/PAS, XRD, UV-Vis/DRS and SEM methods. Additionally, thermal stability of the obtained materials was examined (TGA/DTG/DTA). Photocatalytic activity of the samples was tested in relation to the aqueous solution of Safranin T (initial concentration C0 = 1×10-5 mol L-1) at the visible light (Vis). The results indicate that the mechanochemical synthesis is an effective and simple method for preparing materials with photocatalytic properties. All obtained materials were characterized by greater photocatalytic activity compared to the initial TiO2.

11

Reduction of Copper, Iron, and Lead Content in Laboratory Wastewater Using Zinc Oxide Photocatalyst under Solar Irradiation

Agustina Tuty Emilia, Habiburrahman Muhammad, Amalia Farah, Arita Susila, Faizal Muhammad, Novia, Gayatri Rianyza

Journal of Ecological Engineering

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2022

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Vol. 23, nr 10

107--115

EN

Heavy metal is a type of metal that has a high density and high toxicity when consumed by living things, especially humans. To prevent the impact of environmental pollution, optimal handling of wastewater containing heavy metals is required, including the wastewater from laboratories. This research aimed to study the effect of pH, catalyst dose, and irradiation time on the reduction of Copper (Cu), Iron (Fe), and Lead (Pb) heavy metals and their application to laboratory wastewater treatment. Among the Advanced Oxidation Processes (AOPs) methods, photocatalysis was chosen to reduce the level of Cu, Fe, and Pb heavy metals where zinc oxide (ZnO) is used as a photocatalyst and the sunlight as a light source. To determine the effect of pH, catalyst dose, and time on the reduction of heavy metal levels, firstly, this research used the synthetic wastewater containing Cu, Fe, or Pb heavy metals. On the basis of the experimental results, it is concluded that the pH value, catalyst dose, and time affect the photocatalytic process, decreasing the levels of Cu, Fe, and Pb metals. The optimum pH value obtained for Cu was at pH 7–8, for Fe it was at pH 6, and for Pb it was at pH 8; in turn, the metal removal percentages were 99.46, 99.91, and 99.70%, respectively. In the photocatalysis of synthetic wastewater, high removal percentage of more than 99% was achieved by using 0.1 g/L catalyst. The optimum decrease of metals occurred in the first 15 minutes of solar irradiation where the removal percentage was close to 100%. In this study, the application of ZnO photocatalyst under solar irradiation can reduce the heavy metals content in the laboratory wastewater by almost 100%, which meets the environmental quality standard for Cu, Fe, and Pb.

12

Titanium dioxide as a safe additive to sunscreen emulsions

Janczarek Marcin, Szaferski Waldemar

Chemical and Process Engineering

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2022

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Vol. 43, nr 4

483-–490

EN

Titanium dioxide with its ability to be a UV light blocker is commonly used as a physical sunscreen in the cosmetic industry. However, the safety issues of TiO2 application should be considered more in-depth, e.g., UV light-induced generation of reactive oxygen species which can cause DNA damage within skin cells. The proper modification of titanium dioxide to significantly limit its photocatalytic properties can contribute to the safety enhancement. The modification strategies including the process conditions and intrinsic properties of titanium dioxide were discussed. The selected examples of commercially available TiO2 materials as potential components of cosmetic emulsions dedicated for sunscreens were compared in this study. Only rutile samples modified with Al2O3 and/or SiO2 showed inhibition of photocatalytic activity.

13

Fundamental study of the photocatalytic reduction of CO2: A short review of thermodynamics, kinetics and mechanisms

Gandhi Romil, Moses Aashish, Baral Saroj Sundar

Chemical and Process Engineering

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2022

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Vol. 43, nr 2

223-–228

EN

On the off chance that methods which reduce the global CO2 content are unavailable and inefficient, the increasing CO2 levels will lead to a synchronized rise in temperature across the world. The conversion of this abundant CO2 into hydrocarbons like CH4, CH3OH, CO, HCOOH and hydrogen fuel using different techniques and their use for power could assist with the world’s energy deficiency and solve the CO2 reduction-energy nexus. In this study, photocatalytic CO2 conversion by sunlight will be of primary focus since this bears a resemblance with the regular photosynthesis phenomenon. This work also portrays the writings that have narrated the development of mixtures of two or more carbon ions (C2 ̧) within the photocatalytic reduction of CO2. This paper thus comprises the energy required for CO2 photoreduction, the kinetics mechanisms and thermodynamics requirements. The reaction of CO with water and the hydrogenation of CO2 are covered to understand the gap of Gibb’s free energy between both of the reactions. Likewise, the summary of different metal-based co-catalysts, metal-free co-catalysts and their selectivity towards CO2 reduction by photocatalysis and reduction of CO2 into various hydrocarbons, fuel and materials have also been examined.

14

Nanoparticles for water disinfection by photocatalysis : a review

Bodzek Michał

Archives of Environmental Protection

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2022

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Vol. 48, no. 1

3--17

EN

Photocatalysis is an efficient and ecological method of water and wastewater disinfection. During the process, various microorganisms are deactivated, including Gram-positive and Gram-negative bacteria, for example Escherichia coli, Staphylococcus aureus, Streptococcus pneumonia, and so on, fungi like Aspergillus niger, Fusarium graminearum, algea (Tetraselmis suecica, Amphidinium carterae, and so on) and viruses. Titanium dioxide (TiO2) is the most commonly used material due to its price and high oxidation efficiency; it is easy to modify using both physical and chemical methods, what allows for its wide use in industrial scale. Intensive research on novel photocatalysts (e.g. ZnO and carbon based photocatalysis like graphene, carbon nanotube, carbon nitride and others) has been carried out. The future development of nano-disinfection containing metal/metal oxides and carbon based nanoparticles should focus on: improving disinfection efficiency through different manufacturing strategies, proper clarification and understanding of the role and mechanism of interaction of the nano-material with the microorganisms, progress in scaling up the production of commercial nano-photocatalysts, determination of the extent of environmental release of nano-photocatalysts and their toxicity.

15

Możliwości wykorzystania nanotechnologii i nanomateriałów w procesach uzdatniania wody i oczyszczania ścieków, Cz. 3, Fotokataliza

Bodzek Michał, Konieczny Krystyna

Technologia Wody

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2021

|

Nr 1 (75)

4--18

PL

Fotokataliza jest skuteczną metodą oczyszczania wody i ścieków, umożliwiającą degradację całego spektrum zanieczyszczeń organicznych i nieorganicznych oraz mikroorganizmów. Pomimo intensywnych badań nad innymi fotokatalizatorami (np. ZnO, ZnS, kompozyty półprzewodnikowo-grafenowe, MoS2, WO3 i Fe2O3), tlenek tytanu(IV) (TiO2) pozostaje najpopularniejszym fotokatalizatorem ze względu na swój niski koszt, nietoksyczność i wysoką zdolność utleniania. Co więcej, fotokatalizatory TiO2 można łatwo unieruchomić na różnych powierzchniach i zastosować do oczyszczanie wody i ścieków na dużą skalę. Obecny przegląd ma na celu zwrócenie uwagi na najnowsze osiągnięcia w zakresie fotokatalizy z głównym naciskiem na wykorzystanie nanokatalizatorów. Omówiono wykorzystanie nanofotokatalizy do degradacji takich substancji niebezpiecznych, jak związki endokrynnie czynne (pestycydy, farmaceutyki fenole i inne), barwniki, mikroorganizmy oraz metale ciężkie.

EN

Photocatalysis is an effective method for water and wastewater treatment allowing degradation of a wide spectrum of organic and inorganic pollutants and microorganisms. Despite recent research into other photo-catalysts (e.g. ZnO, ZnS, semiconductor-graphene composites, MoS2, WO3 and Fe2O3), titanium dioxide (TiO2) remains the most popular photo-catalyst due to its low cost, non-toxicity and high oxidation capacity. Moreover, TiO2 photo-catalysts can be easily immobilised on various surfaces and used for large-scale in water and wastewater treatment. The present review aims to highlight the latest developments in photo-catalysis with the main focus on application of nano-catalysts. The use of photocatalysis for the degradation of hazardous substances such as endocrine active compounds (pesticides, phenols, pharmaceuticals and others), dyes, microorganisms and heavy metals is discussed.

16

Time-dependent growth of the dendritic silver prepared using square wave voltammetry technique for methylene blue photodegradation

Budi Setia, Dhanasmoro Lintang, Purwanto Agung, Muhab Sukro

Polish Journal of Chemical Technology

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2021

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Vol. 23, nr 2

60--65

EN

Silver (Ag) particle is a promising photocatalyst material with relatively high catalytic activity and good absorption in the visible light region. A dendritic structure of Ag has been studied in the purpose to enhance photocatalytic activity due to a large surface area and active site number of the metallic Ag particles. In this work, the Ag dendritic structure was synthesized from a surfactant-free electrolyte using the square wave voltammetry technique. The time-dependent growth of the Ag dendrites and their photocatalytic activity on methylene blue (MB) photodegradation are reported. Morphological analysis exhibits the fractal dendritic structure of Ag was found to continuously grow by increasing the deposition time. The Ag dendrites showed a low charge transfer resistance (366.21 Ω) and high specific capacitance (2.09 F/g). A high rate of MB degradation (45.57%) under ultraviolet irradiation indicated that the Ag dendrites produced using this technique are effective for the photocatalytic degradation of MB dye.

17

Gray Water Recovery System Model by Solar Photocatalysis with TiO2 Nanoparticles for Crop Irrigation

Carbajal-Morán Hipólito, Zárate-Quiñones Rosa H., Márquez-Camarena Javier F.

Journal of Ecological Engineering

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2021

|

Vol. 22, nr 4

78--87

EN

The objective of the study was to establish the configuration of the system model to allow the effective recovery of gray water by solar photocatalysis with TiO2 nanoparticles for irrigation of crops. A programmable solar photoreactor based on an S7 1500 PLC and online measurement sensors were used as materials. The inductive method was used to analyze the samples and the deductive method to determine the water quality. The research design used was experimental based on the response surface methodology (MSR) with 20 experiments, 6 of which were central experiments and 6 were axial experiments; these experiments were carried out on sunny days. As a result of the research, a gray water recovery model was obtained, part of this being an electronic system with a programmable photocatalyst, which allowed the development of the experiments. It was concluded that with a solar UV index of 12.21, a dose of titanium dioxide (TiO2) nanoparticles 1.973 g/L and with an exposure period of 60.041 minutes of the solar photocatalyst to UV radiation on sunny days, gray water was recovered in 90% with a confidence level of 95% and a significance α = 0.05, which translates into excellent quality according to the water quality index established in Peru (ICA-PE).

18

Wpływ struktury leków sulfonamidowych na mechanizm inicjacji ich fotokatalitycznej degradacji

Baran Wojciech, Adamek Ewa, Cholewiński Mateusz, Krumpholz Laura, Kulej Barbara, Łazarczyk Antoni, Ledwoń Szymon

Proceedings of ECOpole

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2020

|

Vol. 14, No. 1

69--87

PL

Sulfonamidy, pochodne sulfanilamidu, stanowią dużą grupę leków o właściwościach bakteriostatycznych. Część z nich jest powszechnie wykorzystywana w hodowli zwierząt w celach profilaktycznych i leczniczych. Następnie ich pozostałości trafiają do środowiska, gdzie stanowią uciążliwe i trwałe zanieczyszczenie. Leki te znacznie różnią się podatnością na fotokatalityczną degradację. Prowadzone badania pozwoliły na wyznaczenie związku pomiędzy strukturą sulfonamidów a drogą inicjacji ich rozkładu podczas naświetlania w obecności TiO2. Pozwoliły również na prognozowanie zastosowania procesu fotokatalitycznego do usuwania farmaceutyków z odpadów pohodowlanych.

EN

Sulfonamides, sulfanilamide derivatives, are a large group of drugs with bacteriostatic properties. Some of them are widely used in breeding for prophylactic and therapeutic purposes. Their residues get into the environment (soil, surface waters, and ground waters) where they are regarded as persistent organic pollutant. These drugs differ significantly in susceptibility to photocatalytic degradation. Sulfonamides differ significantly in susceptibility to the photocatalytic degradation. The study allowed to determine the relationship between the sulfonamides structure and the mechanism of initiation of their degradation during UV-A irradiation in the presence of TiO2 as a photocatalyst. Additionally, the results allowed us to develop a project involving the application of the photocatalytic process to the removal of pharmaceuticals from post-culture waste.

19

Air Purification in Sustainable Buildings

Staszowska Amelia

Problemy Ekorozwoju

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2020

|

Vol. 15, nr 2

245--252

EN

This paper concerns the issue of indoor air purification techniques in sustainable public buildings and the residential sector. One of the requirements of sustainable construction is to reduce the energy costs, minimize waste, improve the well-being of users and create green space. The most important certification systems for green (ecological) buildings such as LEED or BREEAM also include the assessment of the indoor environment in terms of the air quality, noise level, building acoustics and energy consumption. Traditional air treatment and purification systems require the use of numerous devices, air transport systems, which are energy-consuming. It is necessary to clean or replace the working elements periodically. The alternative is biophilic installations (green walls) based on the natural properties of plants for removing gaseous pollutants, particulate matter and even bioaerosols from the air. Plants improve humidity, regulate the carbon dioxide concentration, ionize the air and suppress noise. However, the processes of photocatalytic degradation of gaseous compounds are a very promising method of removing impurities, due to low costs, mild process conditions (temperature and pressure) and the possibility of complete mineralization of impurities.

PL

Praca dotyczy zagadnienia technik oczyszczania powietrza wewnętrznego w zrównoważonych budynkach użyteczności publicznej i sektorze mieszkalnym. Jednym z wymogów budownictwa zrównoważonego jest ograniczenie kosztów zużycia energii, minimalizacja powstawania odpadów, poprawa samopoczucia użytkowników oraz tworzenie zielonej przestrzeni. Najważniejsze systemy certyfikacji zielonych/ ekologicznych budynków takie jak LEED czy BREEAM obejmują również ocenę środowiska wewnętrznego w zakresie jakości powietrza, poziomu hałasu, akustyki budynku i jego energochłonności. Tradycyjne systemy uzdatniania i oczyszczania powietrza wymagają wykorzystania licznych urządzeń, systemów przesyłu powietrza świeżego i zużytego, które są energochłonne. Konieczne jest ich okresowe czyszczenie lub wymiana elementów roboczych. Alternatywą są instalacje biofiliczne (zielone ściany) oparte na naturalnych właściwościach roślin do usuwania z powietrza zanieczyszczeń gazowych, pyłów a nawet bioaerozoli. Rośliny poprawiają wilgotność, regulują stężenie dwutlenku węgla, jonizują powietrze i tłumią hałas. Natomiast procesy fotokatalitycznej degradacji związków gazowych są bardzo obiecującą metodą usuwania zanieczyszczeń, ze względu na niewielkie koszty, łagodne warunki prowadzenia procesów (temperatura i ciśnienie) i możliwość całkowitej mineralizacji zanieczyszczeń.

20

Effect of titanium source and sol-gel TiO2 thin film formation parameters on its morphology and photocatalytic activity

Dulian Piotr, Zajic Jan, Żukowski Witold

Materials Science Poland

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2020

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Vol. 38, No. 3

424--433

EN

TiO2 thin films with different surface structure have been prepared from alkoxide solutions by the sol-gel method using different cationic precursors and heat treatment techniques. The effect of using titanium isopropoxide as well as titanium butoxide as a titanium source on the surface structure and photocatalytic activity of the resultant thin films was studied. Significant differences in the rate of hydrolysis and condensation reactions during the sol-gel synthesis were observed for these titanium precursors. This had a direct influence on the morphology of the as-prepared TiO2 films. Higher quality oxide coatings were obtained from titanium isopropoxide. They were characterized by a smaller grain size, improved surface roughness and uniform coverage of the glass substrate. A beneficial effect of calcination process after each sol application cycle in contrast to single step calcination after all dip-coating cycles was observed. Photocatalytic degradation tests showed that methyl orange was decolorized in the presence of all prepared TiO2 films by exposing their aqueous solutions to UV light (λ = 254 nm). The highest photocatalytic activity had the TiO2 layer produced using titanium isopropoxide.