scholarly journals Auto-inhibition effects in anodic oxidation of phenols for electrochemical waste-water purification

2001 ◽  
Vol 66 (11-12) ◽  
pp. 765-784 ◽  
Author(s):  
H. Al-Maznai ◽  
B.E. Conway
Keyword(s):  
Waste Water ◽  
Anodic Oxidation ◽  
Environmental Science ◽  
Oxidation Products ◽  
Waste Waters ◽  
Electrode Surfaces ◽  
Organic Impurities ◽  
High Area ◽  
Oxidation Of Phenols ◽  
Related Compounds

Removal or modification of noxious organic impurities in waste-waters is a major challenge for environmental science. Pollutants such as phenols and their derivatives, as well as PCBs, have attracted special attention. In recent years, the possibilities of effecting direct electrocatalytic oxidations at high-area electrodes such as supported Pt or RuO2 have been investigated. However, in a number of cases, especially with phenolic impurities, application of anodic oxidation fails to lead to continuous Faradaic oxidation currents owing to the electrode surfaces becoming blocked with polymeric oxidation products leading to auto-inhibition (?passivation?) of the desired electrode process. Examples of such effects with phenols and related compounds are examined comparatively in the present paper by means of cyclic volatammetry and chronoamperometry.

scholarly journals SYNTHESIS AND PHOTOCATALYTIC ACTIVITY OF COATINGS TI/TINOM∙ZrO2 FOR PURIFICATION OF INDUSTRIAL WASTE WATER FROM ORGANIC AROMATIC CONTAMINANTS

2021 ◽  
Vol 2 ◽  
pp. 33-40
Author(s):  
V.V. Bykanova ◽  
V.A. Panasenko ◽  
S.M. Bykanov
Keyword(s):  
Waste Water ◽  
Photocatalytic Activity ◽  
Sulfuric Acid ◽  
Anodic Oxidation ◽  
Mixed Oxide ◽  
Industrial Waste ◽  
Electrolyte Solutions ◽  
Industrial Waste Water ◽  
Oxide Systems ◽  
Organic Impurities

It is shown that photocatalytic processes on semiconductor materials are promising for use in technologies for purifying industrial waste water and air from toxic organic impurities for solving important environmental problems. Studies on the formation of coatings with titanium(IV) oxide supplemented with zirconium(IV) oxide have been carried out. The Ti/TiO2 coverings were formed by anodic oxidation of technical alloys of VT1-0 grade titanium and E-125 zirconium from aqueous electrolyte solutions based on 0.5 M sulfuric acid and 1 M potassium pyrophosphate. To obtain mixed oxide coatings of the Ti/TinOm·ZrO2 composition, zirconium(IV) oxide of a given concentration was additionally introduced into the electrolyte solutions. The photocatalytic activity of the obtained systems was assessed by the phenol oxidation reaction. It is shown that, as a result of anodic oxidation of the VT1-0 alloy in sulfuric and pyrophosphate electrolytes, it is possible to obtain mixed oxide systems of the Ti/TinOm·ZrO2 composition with a porous and microcrystalline surface structure and a zirconium content of up to 2 % by weight. It was found that an increase in the pH of the electrolyte leads to a significant decrease in the content of zirconium in the coatings. It is shown that the contact masses Ti/TiO2, Zr/ZrO2, Ti/TinOm·ZrO2 are photocatalytically active in the oxidation of phenol under the action of UV radiation, and the mixed Ti/TinOm·ZrO2 coatings formed from a sulfuric acid electrolyte exhibit a higher catalytic activity with respect to compared with both individual oxides and Ti/TinOm·ZrO2 deposited from pyrophosphate electrolytes. The results obtained indicate the possibility of creating photocatalytic converters using mixed oxide systems formed on metal supports for purifying wastewater from organic aromatic compounds. Keywords: coatings, titanium(IV) oxide, electrochemical anodizing, photocatalytic activity, zirconium(IV) oxide, organic aromatic pollutants, phenol, waste water, purification. Corresponding author Panasenrj V.A. е-mail: [email protected]

The new technology of waste water treatment by using bioreactors with bio membranous movable bed – biochips

2020 ◽  
Vol 10 (3) ◽  
pp. 276-292
Author(s):  
Maria Y. Savostyanova ◽  
◽  
Lidia А. Norina ◽  
Arina V. Nikolaeva ◽  
◽  
...  
Keyword(s):  
Waste Water ◽  
Water Treatment ◽  
Water Resources ◽  
Waste Water Treatment ◽  
Combined Treatment ◽  
Research Work ◽  
Pollution Level ◽  
Waste Waters ◽  
Treatment Facilities ◽  
Movable Bed

Retaining of water resources quality is one of the global ecological problems of the modern time. The most promising direction in solving the problem of water resources protection is the reduction of negative environmental influence of waste water from production facilities by upgrading the existing water treatment technologies. To treat utility water, technical and rain water from site facilities of Transneft system entities, the specialists developed and approved standard technological diagrams, which are used in producing treatment facilities. The standard technological diagrams provide for all necessary stages of waste water treatment ensures the reduction of pollution level to normal values. However, during operation of treatment facilities it was established, that to ensure the required quality of waste water treatment with initially high levels of pollution, the new technological solutions are necessary. The author presents the results of scientific-research work, in the context of which the best affordable technologies were identified in the area of the treatment of waste water with increased content of pollutants and non-uniform ingress pattern. On the basis of the research results the technical solutions were developed for optimization of operation of existing waste water treatment facilities by means of using combined treatment of technical and rain waters and utility waste waters and applying bioreactor with movable bed – biochips. The use of bioreactor with movable bed allows the increase in the area of active surface, which facilitates increase and retention of biomass. Biochips are completely immersed into waste waters, and biofilm is formed on the entire volume of immersion area, facilitating retention of biomass and preventing formation of sediments. Due to mixing the floating device with biofilm constantly moves along the whole area of bioreactor, and, in doing so, speeds up biochemical processes and uniformity of treatment. The advantages of a bioreactor with movable bed – its active sludge durability against increased and changing pollutant concentrations, change of waste water temperature and simplicity of application – ensured the possibility of its use for blending utility waters, technical and rain waters.

Composting of Sewage Sludge of Moscow Waste Water Treatment Plants Using Recycling Filler

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
D.A. Danilovich ◽  
M.N. Kozlov ◽  
V.I. Sklyar ◽  
Yu.A. Nikolaev ◽  
N.M. Shchegolkova ◽  
...  
Keyword(s):  
Waste Water ◽  
Water Treatment ◽  
Waste Water Treatment ◽  
Maximum Temperature ◽  
Waste Waters ◽  
Organic Additives ◽  
Organoleptic Properties ◽  
Water Treatment Plants ◽  
Waste Water Treatment Plants ◽  
The City

This work demonstrates a possibility of composting of municipal waste waters sludge (WWS) digested during 5-7 days, of the Kuryanovo waste water treatment plants (the city of Moscow) without the use of traditional organic additives – sawdust, peat, thatch. As a recycling filler (repeatedly used), enhancing the porosity of the composted mixture, ribbed polyethylene spheres (∅=8 cm) and wood chips (having dimension of 5-10 cm) were used. Composting was performed efficiently in both cases, however, the use of wood ships had technological and economical advantages. The process of composting was carried out during 2-4 weeks and was composed of classical phases of active heating (a rate of 0.2-0.3oC/h was obtained), maintaining of maximum temperature during 1-2 days, and cooling down to the ambient temperature. During the course of composting, a product was obtained, having attractive organoleptic properties, suitable for application in municipal laying-out of greenery.

Discharge of Stable Organic Substances from the Chemical Industries

1994 ◽  
Vol 29 (9) ◽  
pp. 179-185 ◽  
Author(s):  
Åke Undén
Keyword(s):  
Waste Water ◽  
Organic Substances ◽  
Waste Waters ◽  
Major Chemical

In a programme started in 1988, the waste water discharges from the major chemical industries in Sweden have been investigated. The primary objectives were to gather information on the major sources of such discharges and to initiate action so as to achieve significant reductions where required. In this paper the investigation programme is presented together with some early conclusions. As could be expected there are no simple common rules for these industries, each effluent should be considered as a separate problem. It was concluded that these waste waters were in most cases more toxic than was acceptable, and that further purifying measures were required in these cases.

scholarly journals Pathogenic micro-organisms in waste waters from daiies

2000 ◽  
Vol 18 (No. 5) ◽  
pp. 170-174
Author(s):  
P. Navrátilová
Keyword(s):  
Waste Water ◽  
Listeria Monocytogenes ◽  
Activated Sludge ◽  
Cleaning Process ◽  
Waste Waters ◽  
Excess Sludge ◽  
Salmonella Spp ◽  
Potential Health ◽  
Treated Water ◽  
Micro Organisms

Waste waters from dairies were tested for the presence of bacterial pathogens – Listeria monocytogenes, Staphylococcus aureus and Salmonella spp. The prevalence of bacteria was investigated in each stage of the cleaning process (activated sludges systems) too. Two hunder samples of raw waste water, activated sludge, returned activated sludge, excess sludge and treated water from 14 dairies were tested. The samples were all negative for Salmonella spp. From a total of 102 (51%) strains Listeria spp., Listeria inoccua 95 (47.5%) and Listeria monocytogenes 7 (3.5%) were identified. 47 samples were positive for S. aureus. L. monocytogenes were detected in raw waste water 1 (1.6%), in activated sludge 3 (5.5%), in excess sludge 1 and in treated water 2 (3.1%). S. aureus were detected in raw waste water 14 (22.6%), in activated sludge 23 (41.8%), in excess sludge 1 and in treated water 8 (12.3%). These results demonstrate a prevalence of L. monocytogenes and S. aureus in waste waters from dairies. During the cleaning process pathogenic bacteria were not devitalized. The excess sludge and treated water including pathogenic micro-organisms represent a potential health hazard.

scholarly journals Introduction of the CP concept in a Factory for the production of welding electrodes Piva, Pluzine

2009 ◽  
Vol 15 (1) ◽  
pp. 53-56
Author(s):  
M. Vukcevic ◽  
D. Blecic ◽  
Z. Blecic ◽  
D. Cabarkapa
Keyword(s):  
Waste Water ◽  
Raw Materials ◽  
Cleaner Production ◽  
Waste Waters ◽  
Technical Modifications ◽  
Coated Electrodes

The new concept of Cleaner Production (CP) was recently introduced in the Factory for the production of welding electrodes (FEP) in Pluzine, by following some activities, raw materials and products. By the identification of some sub-processes with CP opportunities, focus points were identified and subjected to some technical modifications and innovations. The most significant results were obtained regarding waste waters, through the modifications of existing waste water generation and a possible switch to an other technology, the reduction of K-silica waste through a technological modification, a system of powder transport, as well as the production of coated electrodes.

Anodic Oxidation of Anthracenes and Related Compounds. Part I. Hydroxylation of Anthracene.

1970 ◽  
Vol 24 ◽  
pp. 2757-2767 ◽  
Author(s):  
Vernon D. Parker ◽  
Bernt Carnmalm ◽  
Berndt Sjöberg ◽  
P. Karrer ◽  
Akira Shimizu
Keyword(s):  
Anodic Oxidation ◽  
Related Compounds
Sign in / Sign up

Export Citation Format

Share Document