scholarly journals The Application of Ozone to Reduce the Coloring Intensity of Aqueous Solutions of Dyes Used in the Textile Industry

2020 ◽  
Vol 212 ◽  
pp. 01001
Author(s):  
Sergey Belov ◽  
Grigoriy Naumchik

The article discusses the mechanisms of interaction of ozone with aqueous solutions of organic dyes. Two different dyes with different types of chromophore systemwere investigated: azo dye and thiazine dye. A detailed methodology for performing experimental studies makes it possible to accurately dose ozone into the reaction mixture. The data of experimental studies are presented indicating the effectiveness of the use of ozone for the destruction of dyes in aqueous solutions. The specific doses of ozone were established to reduce the color intensity of the studied dye solutions to standard values.

Proceedings ◽  
2019 ◽  
Vol 16 (1) ◽  
pp. 56
Author(s):  
Jędrys-Wolska ◽  
Korus

Colored industrial wastewater is a threat in many environmental aspects. As such, there is a need to find more effective methods for its purification. This article presents a brief overview of available methods for removing dyes from aqueous solutions, among them the adsorption process, which is the subject of this study. The course of preliminary tests on the process of cleaning dye solutions in the adsorption process is presented. Unmodified magnetite and magnetite modified with polymers were used as adsorbents. The synthesis of particular types of magnetite, the adsorption process, as well as the methods of further analyzes are described. As part of the work, the focus was put on a comparison of the effectiveness of the purification process for different types of adsorbents in relation to selected dyes. The varied conditions of the process were also analyzed. It has been shown that magnetite is an adsorbent that is easy to use, allowing effective separation of dyes of various chemical structures from aqueous solutions. The effectiveness of the process depends on the type of dye and on the pH value and can be increased in relation to some dyes by using magnetite modification with selected polymers.


1997 ◽  
Vol 36 (2-3) ◽  
pp. 155-163 ◽  
Author(s):  
S. Liakou ◽  
M. Kornaros ◽  
G. Lyberatos

Wastewaters produced in textile industrial processes contain organic dyes which are not easily amenable to biological treatment. Pretreatment with ozone is a promising method for oxidation of those dyes to more degradable compounds. The aim of this work is to assess the oxidation kinetics of a specific azo dye used in the textile industry, Orange II. Batch experiments were conducted in order to elucidate the oxidation route of the dye. Oxalate, formate and benzenesulfonate are found to be the oxidation intermediate compounds. A mathematical model which describes the dye elimination, the COD and BOD5 variation, the amount of ozone reacted and the time evolution of the intermediate compounds has been developed.


Author(s):  
Anna S. Manukyan ◽  
Mikael Belay Seyoum ◽  
Vladimir V. Rybkin

This review examines the processes of degradation of organic dyes in their aqueous solutions under the action of atmospheric pressure discharges. These processes are important for solving the environmental problem associated with the purification of water from organic pollution. A brief description of the types of discharges used for these purposes is given - dielectric barrier discharge, pulsed corona discharge, gliding arc discharge, direct current glow discharge, diaphragm discharge, and contact glow discharge electrolysis. The results are given on the degree of degradation of more than 30 types of dyes in different types of discharges. The features of comparing different types of discharges in terms of their energy efficiency of the degradation process - the energy spent on the decomposition of one gram of dye - are discussed. The kinetic regularities of the decomposition process and the influence on them of various factors - the initial concentration of the dye, the discharge power, and the pH of the solution are considered. Possibilities of accelerating degradation using homogeneous and heterogeneous catalysts are discussed. Possible mechanisms of the ongoing processes and the participation in them of active particles formed in solution under the action of a discharge (OH, HO2 and ozone radicals) are analyzed.


Author(s):  
Б.И. Гельцер ◽  
Э.В. Слабенко ◽  
Ю.В. Заяц ◽  
В.Н. Котельников

Одним из основных требований к разработке экспериментальных моделей цереброваскулярных заболеваний является их максимальная приближенность к реальной клинической практике. В работе систематизированы данные по основным методам моделирования острой ишемии головного мозга (ОИГМ), представлена их классификация, анализируются данные о преимуществах и недостатках той или иной модели. Обсуждаются результаты экспериментальных исследований по изучению патогенеза ОИГМ с использованием различных моделей (полной и неполной глобальной, локальной и мультифокальной ишемии) и способов их реализации (перевязка артерий, клипирование, коагуляция, эмболизация и др.). Особое внимание уделяется «стабильности» последствий острого нарушения мозгового кровообращения: необратимых ишемических повреждений головного мозга или обратимых с реперфузией заданной продолжительности. Отмечается, что важное значение в этих исследованиях должно принадлежать современным методам прижизненной визуализации очагов острого ишемического повреждения, что позволяет оценивать динамику патологического процесса. Предлагаемый метод отвечает требованиям гуманного обращения с животными. Подчеркивается, что выбор релевантной модели ОИГМ определяется задачами предстоящего исследования и технологическими ресурсами научной лаборатории. Development of experimental models for acute forms of cerebrovascular diseases is essential for implementation of methods for their prevention and treatment. One of the principal requirements to such models is their maximum approximation to actual clinical practice. This review systematized major models of acute cerebral ischemia (ACI), their classification, and presented information about their advantages and shortcomings. Also, the review presented results of experimental studies on pathophysiological mechanisms of different types of modeled ACI (complete and incomplete global, local, and multifocal ischemia) and methods for creating these models (arterial ligation, clipping, coagulation, embolization, etc.). Particular attention was paid to “stability” of the consequences of acutely impaired cerebral circulation - an irreversible ischemic brain injury or a reversible injury with reperfusion of a given duration. The authors emphasized that in such studies, a special significance should be given to intravital imaging of acute ischemic damage foci using modern methods, which allow assessing the dynamics of the pathological process and meet the requirements to humane treatment of animals. The choice of a relevant ACI model is determined by objectives of the planned study and the technological resources available at the research laboratory.


2019 ◽  
Vol 25 (34) ◽  
pp. 3645-3663 ◽  
Author(s):  
Muhammad Ismail ◽  
Kalsoom Akhtar ◽  
M.I. Khan ◽  
Tahseen Kamal ◽  
Murad A. Khan ◽  
...  

: Water pollution due to waste effluents of the textile industry is seriously causing various health problems in humans. Water pollution with pathogenic bacteria, especially Escherichia coli (E. coli) and other microbes is due to the mixing of fecal material with drinking water, industrial and domestic sewage, pasture and agricultural runoff. Among the chemical pollutants, organic dyes due to toxic nature, are one of the major contaminants of industrial wastewater. Adequate sanitation services and drinking quality water would eliminate 200 million cases of diarrhea, which results in 2.1 million less deaths caused by diarrheal disease due to E. coli each year. Nanotechnology is an excellent platform as compared to conventional treatment methods of water treatment and remediation from microorganisms and organic dyes. In the current study, toxicity and carcinogenicity of the organic dyes have been studied as well as the remediation/inactivation of dyes and microorganism has been discussed. Remediation by biological, physical and chemical methods has been reviewed critically. A physical process like adsorption is cost-effective, but can’t degrade dyes. Biological methods were considered to be ecofriendly and cost-effective. Microbiological degradation of dyes is cost-effective, eco-friendly and alternative to the chemical reduction. Besides, certain enzymes especially horseradish peroxidase are used as versatile catalysts in a number of industrial processes. Moreover, this document has been prepared by gathering recent research works related to the dyes and microbial pollution elimination from water sources by using heterogeneous photocatalysts, metal nanoparticles catalysts, metal oxides and enzymes.


1995 ◽  
Vol 60 (9) ◽  
pp. 1448-1456 ◽  
Author(s):  
Ivo Šafařík ◽  
Miroslava Šafaříková ◽  
Vlasta Buřičová

Magnetic composite based on poly(oxy-2,6-dimethyl-1,4-phenylene) (PODMP) was prepared by melting the polymer with ε-caprolactam in a presence of fine magnetite particles. Magnetic PODMP was used for sorption of water soluble organic compounds (dyes belonging to triphenylmethane, heteropolycyclic and azo dye groups) from water solutions. There were considerable differences in the binding of the dyes tested. In general, heteropolycyclic dyes exhibited the lowest sorption.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2506
Author(s):  
Wamidh H. Talib ◽  
Ahmad Riyad Alsayed ◽  
Alaa Abuawad ◽  
Safa Daoud ◽  
Asma Ismail Mahmod

Melatonin is a pleotropic molecule with numerous biological activities. Epidemiological and experimental studies have documented that melatonin could inhibit different types of cancer in vitro and in vivo. Results showed the involvement of melatonin in different anticancer mechanisms including apoptosis induction, cell proliferation inhibition, reduction in tumor growth and metastases, reduction in the side effects associated with chemotherapy and radiotherapy, decreasing drug resistance in cancer therapy, and augmentation of the therapeutic effects of conventional anticancer therapies. Clinical trials revealed that melatonin is an effective adjuvant drug to all conventional therapies. This review summarized melatonin biosynthesis, availability from natural sources, metabolism, bioavailability, anticancer mechanisms of melatonin, its use in clinical trials, and pharmaceutical formulation. Studies discussed in this review will provide a solid foundation for researchers and physicians to design and develop new therapies to treat and prevent cancer using melatonin.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Phitchan Sricharoen ◽  
Supalak Kongsri ◽  
Chunyapuk Kukusamude ◽  
Yonrapach Areerob ◽  
Prawit Nuengmatcha ◽  
...  

AbstractWe report a novel method for the synthesis of 3-mercaptopropyl trimethoxysilane-modified hydroxyapatite (FHAP-SH) derived from fish-scale residues by using ultrasound irradiation. Scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy were used for the FHAP-SH characterization. Then, the organic dye adsorption on the FHAP-SH was monitored through an ultrasound process. After the dye removal optimization, significant improvements were observed in the maximum adsorption capacities for Congo Red (CR, 500 mg g−1), Coomassie Brilliant Blue G 250 (CB, 235 mg g−1), and Malachite Green (MG, 625 mg g−1). The adsorption behaviors of these dyes were fitted by using the Langmuir isotherm model with a high coefficient of determination values ranging from 0.9985 to 0.9969. The adsorption of the three dyes onto FHAP-SH was an endothermic process based on the adsorption thermodynamics model, while the adsorption kinetics analysis of the dyes presented a good alignment with the pseudo-second-order kinetics. The FHAP-SH exhibits a remarkably high adsorption capacity, is inexpensive, and fulfills the ecofriendly requirements of dye wastewater treatment, especially in the textile industry.


Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 39
Author(s):  
Qi Chen ◽  
Zhicheng Yan ◽  
Hao Zhang ◽  
KiBuem Kim ◽  
Weimin Wang

Al-based metallic glasses have a special atomic structure and should have a unique degradation ability in azo dye solutions. The Al88Ni9Y3 (Y3), Al85Ni9Y6 (Y6) and Al82Ni9Y9 (Y9) glassy ribbons are melt spun and used in degrading methyl orange (MO) azo dye solution with adding H2O2. With increasing cY, the as-spun ribbons have an increasing GFA (glass formability) and gradually decreased the degradation rate of MO solution. TEM (transmission electron microscopy) results show that the Y3 ribbon has nano-scale crystallites, which may form the channels to transport elements to the surface for degrading the MO solution. After adding H2O2, the degradation efficiency of Al-based glasses is improved and the Y6 ribbon has formed nano-scale crystallites embedded in the amorphous matrix and it has the largest improvement in MO solution degradation. These results indicate that forming nano-scale crystallites and adding H2O2 are effective methods to improve the degradation ability of Al-based glasses in azo dye solutions.


2012 ◽  
Vol 29 (7) ◽  
pp. 685-692 ◽  
Author(s):  
Thaisa P.F. Teixeira ◽  
Simone I. Pereira ◽  
Sergio F. Aquino ◽  
Anderson Dias

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