scholarly journals Evaluation of the kinetics of oxidation and removal of organic matter in the self-purification of a mountain river

DYNA ◽  
2015 ◽  
Vol 82 (191) ◽  
pp. 183-193 ◽  
Author(s):  
Jorge Virgilio Rivera Gutiérrez
Keyword(s):  
Water Quality ◽  
Water System ◽  
The Self ◽  
Organic Load ◽  
Mountain River ◽  
Kinetics Of Oxidation ◽  
Kinetic Rates ◽  
High Concentrations ◽  
Kinetics Of

The study is based on the determination of the kinetic rates and assessment of self-purification of the Frio River, due to the uptake of organic load. The kinetic rates were calculated by applying differential and logarithmic methods on concentrations of water quality determinants present in each of the (7) reach of the river. The water system easily recovers the amount of oxygen, k<sub>d</sub>= 0.4, k<sub>a</sub> 3.2 d<sup>-1</sup>, only receives 27.7 Ton. d<sup>-1</sup>, the organic load, making high concentrations of carbon, ammonium and remain sediment. The length Influence of discharges, LIV- BOD yielded a mean per tranche of 10 km, compared to 3 km each way, means that the river can´t self- purification that need more length of travel. The study illustrates the modeling of the determinants of quality, developed by the QUAL2K, using the calculated rates.

The kinetics of the catalytic oxidation over palladium of some alkanes and cycloalkanes

1976 ◽  
Vol 349 (1659) ◽  
pp. 523-534 ◽  
Keyword(s):  
Gas Phase ◽  
Surface Oxidation ◽  
Reaction Rates ◽  
Optimum Operating ◽  
Optimum Operating Temperature ◽  
Kinetics Of Oxidation ◽  
Low Concentrations ◽  
Diffusion Effects ◽  
Kinetics Of

Measurements have been made of the kinetics of oxidation over palladium of the C 1 to C 4 alkanes, cyclopropane and cyclohexane in the temperature range 588-873 K by means of a microcalorimetric bead technique. With an initially reduced and degassed catalyst, reaction rates for the alkanes increase from C 1 to C 4 , while butane, cyclopropane and cyclohexane are of comparable reactivity. The rates of oxidation of the alkanes are significantly increased when the catalyst is preheated in oxygen, and cyclo­propane oxidation is markedly enhanced by this procedure. Reactions are inhibited by gas-phase diffusion effects, particularly at higher tempera­tures; there is thus apparent inhibition by oxygen. All the reactions are preceded by the surface oxidation of the catalyst, this latter process having an activation energy of 176 ± 18 kJ mol -1 . Reaction appears to involve the interaction of hydrocarbon from the gas phase with palladium oxide, followed by the rapid desorption of carbon dioxide and the slower desorption of water. Large concentrations of water vapour cause a loss of catalytic activity, probably due to the formation of palladium hydroxide. When the bead system is used for the detection of low concentrations of hydrocarbons, the optimum operating temperature lies between 793 and 723 K, decreasing as the hydrocarbons become more reactive. The most significant single factor governing response is the heat of combustion, so that this method is most sensitive for the determination of high molecular mass hydrocarbons.

The mechanisms of oxidation of formaldehyde and formic acid by ions of chromium (VI), vanadium (V) and cobalt (III)

1963 ◽  
Vol 274 (1359) ◽  
pp. 480-499 ◽  
Keyword(s):  
Formic Acid ◽  
Chromic Acid ◽  
Isotope Effects ◽  
Secondary Alcohol ◽  
Kinetics Of Oxidation ◽  
Chromium Vi ◽  
Kinetic Isotope ◽  
Kinetics Of ◽  
Cyclic Intermediate

The kinetics of oxidation of formaldehyde, formic acid and their deuterated isomers have been studied with chromic acid (part A) and also with vanadium (v), and cobalt (III) as oxidants (part B). In each case the reaction mechanism resembles that for the oxidation of a secondary alcohol by the same oxidant. Thus formaldehyde is oxidized in its hydrated form, H 2 C(OH) 2 . The quantitative study of kinetic and solvent effects leads to clarification of further details concerning secondary stages in the oxidations effected by chromic acid, whilst the determination of thermodynamic parameters for the oxidations by one electron abstracting reagents (part B) shows that any direct correlation between activation energies and kinetic isotope effects involves unwarrantable assumptions. It is probable that these reactions proceed through cyclic intermediate complexes.

scholarly journals Determination of the Physicochemical and Microbiological Index of the River Chakvistskali

2021 ◽  
Author(s):  
Nino Lomtatidze ◽  
Marine Gvianidze
Keyword(s):  
Water Quality ◽  
Water Resources ◽  
Environmental Impact ◽  
The Self ◽  
Water Bodies ◽  
Anthropogenic Load ◽  
Anthropogenic Factors ◽  
Anthropogenic Eutrophication ◽  
Water Ecosystem

The growing impact of the anthropogenic factors on the environment has intensified the importance of protecting the water ecosystem. The degrading of water resources is a frequent result of the anthropogenic eutrophication resulting in imbalance of substance levels and deterioration of sanitation and recreational condition of water. The environmental impact of contaminants is manifested at the level of organisms, populations, biocenosis, and ecosystems. In the context of the increased anthropogenic load, the growing contamination of water bodies impairs the self-cleansing capacity of water, causes eutrophication and reduces water quality.

scholarly journals Spatio-temporal Assessment of Land-based Pollutants in Water Resources: Yalova, Turkey

2019 ◽  
Vol 7 (3) ◽  
pp. 417
Author(s):  
Oylum Gökkurt Baki
Keyword(s):  
Water Quality ◽  
Iron Phosphate ◽  
Ammonium Nitrogen ◽  
Quality Parameters ◽  
Monthly Basis ◽  
Total Copper ◽  
Spatio Temporal ◽  
High Concentrations ◽  
To Receive

The study investigated the water quality characteristics of the spring waters, creeks and lakes in Yalova Province, Turkey. The 12-month study was carried out in 2005 and the same study was repeated in the same stations in 2008. Water samples were collected from 9 stations on a monthly basis. For the determination of the water quality, dissolved oxygen, pH, temperature, ammonium nitrogen, nitrite and nitrate nitrogen, potassium, total copper, chlorine, sulphate, iron, phosphate, zinc and sulfide analyses were performed. The water quality parameters of the spring waters, creeks and lakes were determined with respect to months and years. The stations that are known to receive wastewater and solid waste inputs were revealed to have high concentrations of water pollution-indicating parameters.

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