scholarly journals Self-purification ability of natural waters in the arid zones

2018 ◽  
pp. 36-42
Author(s):  
Sofiya Romanova ◽  
Roza Ryskaliyeva ◽  
Oksana Ponomarenko
Keyword(s):  
Metal Ions ◽  
Clay Minerals ◽  
Natural Waters ◽  
The Self ◽  
Sorption Properties ◽  
Dynamic Mode ◽  
Arid Zones ◽  
Water Reservoirs ◽  
Lake Balkhash ◽  
Closed Lake

The paper presents the analysis of literature data and research results on self-purification and self-purification ability of natural waters at arid zones (on example of closed Lake Balkhash). The self-purification processes are a combination of all natural (hydrodynamic, chemical, microbiological and hydrobiological) processes in contaminated natural waters. A large number of pollutants and specific (physical and geographical) conditions of reservoirs causes the complexity and variety of cleaning processes of natural waters. Large amounts of pollutants discharged into water reservoirs and drains impede the self-purification processes. It has been established that the sediments and clay of Lake Balkhash absorb the metal ions. Thus, the process of absorption of Mn2+ ions by clay minerals mainly occurs within the first three hours of contact, whereas sorption by slits continues until 10-15 days. The sediments are good absorbents for cadmium (90%), zinc (86%) and copper (78%). The sorption properties in the dynamic mode decreases in the row of zeolite (SEC = 1.02·10-3), then Fe (OH)3 (SEC = 0.28·10-3) and Al (OH)3 (SEC = 0.10·10-3 mmol-eq/g) with respect to Mn+2 ion with concentrations from 5.0 to 100 μg/L.

Rates of Reaction of Dissolved Oxygen With Scavengers in Sweet and Sour Brines

CORROSION ◽  
1969 ◽  
Vol 25 (10) ◽  
pp. 397-404 ◽  
Author(s):  
E. S. SNAVELY ◽  
F. E. BLOUNT
Keyword(s):  
Transition Metal ◽  
Dissolved Oxygen ◽  
Metal Ions ◽  
Induction Period ◽  
Natural Waters ◽  
Reaction Rate ◽  
Transition Metal Ions ◽  
Zero Order ◽  
Laboratory Apparatus ◽  
High Ph

Abstract Rates of reaction of dissolved oxygen with H2S were measured in a laboratory apparatus using a polarographic type instrument for the measurement of oxygen concentrations. Results show that oxidation occurs only at high pH in the absence of catalytic species. The reaction is catalyzed by transition metal ions in the order Ni++>Co ++>Mn++>Cu++>Fe++. In all cases, the reaction rate increases with pH and is at first complex but becomes zero-order with respect to oxygen after a brief induction period. Some natural waters contain sufficient catalysts that additional amounts are not required for scavenging O2 with SO2 or Na2SO3. Sour waters cannot be scavenged with SO2 or Na2SO3 because of ineffectiveness of catalysts.

scholarly journals The origin of life: the first self-replicating molecules were nucleotides

2019 ◽  
Author(s):  
Ken Ohsaka
Keyword(s):  
Origin Of Life ◽  
Clay Minerals ◽  
The Self ◽  
Rna Molecules ◽  
Simulated Environments ◽  
The Origin Of Life ◽  
Prebiotic Earth ◽  
Self Replication

Difficulties to synthesize RNA nucleotides from their subunits in modern labs under simulated environments leads us to propose a possible process for the synthesis by cross complimentary self-replication with help of clay minerals, which might be operated on prebiotic Earth. Clay minerals are known to be good catalysts and certainly existed on prebiotic Earth. The self-replication of RNA nucleotides (monomers) may be considered as the origin of potential self-replication of some extant RNA polymers, and also the reason for homochirality of RNA molecules.

Complexation of Dissolved Organic Matter with Trace Metal Ions in Natural Waters

2012 ◽  
pp. 769-849 ◽  
Author(s):  
Khan M. G. Mostofa ◽  
Cong-qiang Liu ◽  
Xinbin Feng ◽  
Takahito Yoshioka ◽  
Davide Vione ◽  
...  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Trace Metal ◽  
Metal Ions ◽  
Natural Waters ◽  
Trace Metal Ions

Construction of homochiral alkaline–lanthanide heteronuclear helicates with Na+-selective bonding in the self-assembly process

2019 ◽  
Vol 48 (39) ◽  
pp. 14595-14599 ◽  
Author(s):  
Ge Li ◽  
Li Wang ◽  
Qingxin Han ◽  
Weisheng Liu
Keyword(s):  
Metal Ions ◽  
Self Assembly ◽  
The Self ◽  
Assembly Process

A supramolecular approach to distinguish Na+ from other biologically important metal ions.

scholarly journals Sorption of Heavy Metal Ions of Chromium, Manganese, Selenium, Nickel, Cobalt, Iron from Aqueous Acidic Solutions in Batch and Dynamic Conditions on Natural and Synthetic Aluminosilicate Sorbents

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5271
Author(s):  
Jolanta Flieger ◽  
Justyna Kawka ◽  
Wojciech Płaziński ◽  
Rafał Panek ◽  
Jarosław Madej
Keyword(s):  
Metal Ions ◽  
Fixed Bed ◽  
Sorption Properties ◽  
Column Studies ◽  
Acidic Solutions ◽  
Nickel Cobalt ◽  
X Zeolite ◽  
Synthetic Zeolites ◽  
The Individual ◽  
Natural And Synthetic

Zeolites are materials with known sorption properties. The sorption is thought to progress mainly by ion exchange with Na+, K+, Mg2+, Ca2+ or H+ from the zeolite exchange sites. The aim of the study was to compare the sorption properties of natural and synthetic zeolites on the example of the removal of selected metals from aqueous acidic solutions. Uptake experiments for selected ions of chromium, manganese, selenium, nickel, cobalt, and iron were performed using the batch and kinetic column methods. The sorption of the individual metal ions in mg per 1g of sorbent was determined for each sorbent. The relative affinity sequence of the examined cations toward the various sorbent was presented. The Langmuir model was used to model the adsorption equilibrium. Vermiculite under 1 mm of diameter (SF), Na-X, and Na-A were proved to be the most suitable for the individual uptake of studied metal ions. It was observed that the behavior of selenium ions differed from the remaining ones which was interpreted that selenium undergoes adsorption in the anionic form. The fixed-bed column studies were performed using Na-A, ensuring the sorption of selenium in the presence of iron(III) ions. The experiments were conducted using Na-X zeolite pre-loaded by Fe(III) as well as unmodified sorbent eluted by an equimolar mixture containing 100 ppm of Fe and Se. Obtained results prove that selenium sorption improves if other metal ions such as iron appear in the acidic solution. That efficient selenium sorption conditions can be applied to remove selenium which was recognized as toxic at higher levels.

The State of Metal Ions in Natural Waters

1984 ◽  
Vol 12 (4) ◽  
pp. 335-361 ◽  
Author(s):  
P. N. Linnik ◽  
B. I. Nabivanets
Keyword(s):  
Metal Ions ◽  
Natural Waters ◽  
The State

Sorption Properties of Fly Ash Microspheres of Thermal Power Plants

2019 ◽  
Vol 23 (1) ◽  
pp. 50-54 ◽  
Author(s):  
A.I. Fomenko ◽  
L.I. Sokolov
Keyword(s):  
Heavy Metal ◽  
Fly Ash ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Power Plants ◽  
Thermal Power ◽  
Sorption Properties ◽  
Thermal Power Plants ◽  
Iron Ions ◽  
Quantitative Characteristics

The sorption characteristics of aluminosilicate microspheres of fly ash from thermal power plants with respect to heavy metal ions were studied with a view to their subsequent use for integrated treatment of household and industrial wastewater. The mechanism and kinetics of the sorption of total iron ions from aqueous solutions are studied, quantitative characteristics of the sorption capacity and adsorption equilibrium constants are obtained. It has been established that aluminosilicate microspheres of fly ash possess sorption properties with respect to common iron ions. The sorption isotherm of iron ions from water by the material under study is characteristic of microporous sorbents. The quantitative characteristics of the sorption process allow us to conclude about the possibility of using aluminosilicate fly ash microspheres without any additional treatment for the purification of waste water from heavy metal ions.

Sign in / Sign up

Export Citation Format

Share Document