Prediction of K-Ca-Mg ternary exchange from binary isotherms in volcanic soils using the Rothmund-Kornfeld approach

Soil Research ◽  
2002 ◽  
Vol 40 (5) ◽  
pp. 781 ◽  
Author(s):  
M. Escudey ◽  
P. Diaz ◽  
J. E. Förster ◽  
G. Galindo ◽  
C. Pizarro ◽  
...  
Keyword(s):  
Ionic Strength ◽  
Cation Exchange ◽  
Surface Charge ◽  
Cation Exchange Capacity ◽  
Binary Data ◽  
Exchange Capacity ◽  
Volcanic Soils ◽  
Experimental Conditions ◽  
Equivalent Fractions ◽  
Variable Surface

The Gaines-Thomas formulation of the Rothmund-Kornfeld equation was used to predict the K-Ca-Mg exchange in variable surface charge soils. Binary and ternary equilibria were carried out at 25°C and at constant ionic strength of 0.050 mol/L. The selectivity sequence K > Ca > Mg was observed in binary isotherms. The experimental ternary isotherms are well described from binary data. When experimental v. calculated equivalent fractions were plotted, slopes between 0.901 and 1.051, and correlations between 0.970 and 0.986, were obtained. The design used assures in volcanic soils that no, or minor, changes in surface charge, cation exchange capacity, and selectivity occur, but the predicted ternary values are restricted to the same binary experimental conditions employed.

Effects of pH and ionic strength on the cation exchange capacity of soils with variable charge

Soil Research ◽  
1981 ◽  
Vol 19 (1) ◽  
pp. 93 ◽  
Author(s):  
GP Gillman
Keyword(s):  
Ionic Strength ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Surface Soils ◽  
Ph Values ◽  
Variable Charge ◽  
Effects Of Ph ◽  
Variable Charge Soils

The cation exchange capacity of six surface soils from north Queensland and Hawaii has been measured over a range of pH values (4-6) and ionic strength values (0.003-0.05). The results show that for variable charge soils, modest changes in electrolyte ionic strength are as important in their effect on caton exchange capacity as are changes in pH values.

Cation and Anion Sorption Capability of Organophilic Bentonite

1997 ◽  
Vol 506 ◽  
Author(s):  
J. Bors ◽  
St. Dultz ◽  
B. Riebe
Keyword(s):  
Cation Exchange ◽  
Surface Charge ◽  
Cation Exchange Capacity ◽  
Particle Surface ◽  
Exchange Capacity ◽  
Negative Particle ◽  
Strontium Ions ◽  
Wyoming Bentonite

ABSTRACTSorption experiments were performed with iodide, cesium and strontium ions on MX-80 Wyoming-bentonite treated with hexadecylpyridinium (HDPy+) in amounts equivalent to 0.2 - 4.0 times the cation exchange capacity (CEC) using 125I- 134Cs+ and 85Sr2+ as tracers. In HDPy-bentonite, iodide exhibited increasing adsorption, while cesium and strontium ions showed decreasing adsorption with increasing organophilicity. It was also found that the Cs+affinity to original and HDPy-bentonite was considerably higher than that of Sr2+ ions. HDPy+ uptake in increasing concentrations resulted in a pronounced expansion of the basal spacings (d002 reflex at 2.78 nm) and in a change of the negative particle surface charge to positive values.

scholarly journals Analysis of the sorption properties of different soils using water vapour adsorption and potentiometric titration methods

2016 ◽  
Vol 30 (3) ◽  
pp. 369-374 ◽  
Author(s):  
Kamil Skic ◽  
Patrycja Boguta ◽  
Zofia Sokołowska
Keyword(s):  
Specific Surface ◽  
Cation Exchange ◽  
Surface Charge ◽  
Surface Area ◽  
Water Vapour ◽  
Potentiometric Titration ◽  
Specific Surface Area ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Sorption Properties

Abstract Parameters of specific surface area as well as surface charge were used to determine and compare sorption properties of soils with different physicochemical characteristics. The gravimetric method was used to obtain water vapour isotherms and then specific surface areas, whereas surface charge was estimated from potentiometric titration curves. The specific surface area varied from 12.55 to 132.69 m2 g−1 for Haplic Cambisol and Mollic Gleysol soil, respectively, and generally decreased with pH (R=0.835; α = 0.05) and when bulk density (R=−0.736; α = 0.05) as well as ash content (R=−0.751; α = 0.05) increased. In the case of surface charge, the values ranged from 63.00 to 844.67 μmol g−1 Haplic Fluvisol and Mollic Gleysol, respecively. Organic matter gave significant contributions to the specific surface area and cation exchange capacity due to the large surface area and numerous surface functional groups, containing adsorption sites for water vapour molecules and for ions. The values of cation exchange capacity and specific surface area correlated linearly at the level of R=0.985; α = 0.05.

A proposed method for the measurement of exchange properties of highly weathered soils

Soil Research ◽  
1979 ◽  
Vol 17 (1) ◽  
pp. 129 ◽  
Author(s):  
GP Gillman
Keyword(s):  
Ionic Strength ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Barium Chloride ◽  
Exchange Capacity ◽  
Potential Surfaces ◽  
Exchange Method ◽  
Barium Chloride Solution ◽  
Highly Weathered Soils ◽  
Basic Cations

The 'compulsive exchange' method of Bascomb has been modified to allow the determination of cation exchange capacity and anion exchange capacity of soils containing significant quantities of constant potential surfaces. The soil is equilibrated with unbuffered barium chloride solution at an ionic strength approximating that of the soil solution, so that the conditions under which determinations are made are similar to those found in the field. Barium on the exchange complex is then replaced by magnesium when the latter is added as magnesium sulfate, and this is accomplished without altering the solution ionic strength. If desired, exchangeable basic cations can be determined as an additional step in the procedure. Results obtained by the proposed method are compared with other commonly used procedures for determining cation exchange capacity and exchangeable basic cations.

scholarly journals Adsorption Potentials of Alfisol on Glyphosate and Cadmium Contaminants

2020 ◽  
pp. 25-33
Author(s):  
F. B. Okanlawon ◽  
O. O. Awotoye ◽  
P. O. Ogunbamowo
Keyword(s):  
Ionic Strength ◽  
Organic Carbon ◽  
Cation Exchange ◽  
Soil Sample ◽  
Adsorption Capacity ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Initial Concentration ◽  
University Of Ibadan ◽  
Ibadan Nigeria

Aims: This study aimed at demonstrating the adsorption capacity as well as the removal of glyphosate and cadmium unto Alfisols. Place and Duration of Study: Research was carried out in Analytical Laboratory of Department of Chemistry, University of Ibadan, Nigeria. The soil sample was collected from an undisturbed forest land, University of Ibadan, Nigeria. Methodology: The soil sample was air dried for 72 hours under ambient temperature and allowed to pass through 2 mm sieve before use. All solutions and soil dispersions were prepared using de-ionised water. The pH, organic carbon, particle size, exchangeable cations, cation exchange capacity, available phosphorus and soil total nitrogen were all analysed for in the soil sample following the standard procedures likewise the cadmium and glyphosate adsorption/adsorbent studied. Results: The pH of the soil is slightly acidic with high total organic carbon, while the cation exchange capacity is on the lower side. The textural class of the soil greatly influences its water retention capacity, thus the soil under study is predominantly sandy. A decrease in the equilibrium adsorption capacity was observed when the adsorbent dose was increased from 0.2 – 0.8 g however, with a sharp increase at a dose of 1 g. An increase in the percentage cadmium removal was observed with increase in pH from 48.80% to a maximum of 91.10% at neutral pH. The result also indicates that increasing the initial concentration of the cadmium ions and glyphosate lead to an increase in the uptake capacity of the soil for both adsorbate. At higher ionic strength of 0.1 M, the peak removal was obtained at initial concentration of 10 ppm which eventually attains equilibrium at other concentration level. Conclusion: Alfisol can therefore concluded to be an adsorbent provided some conditions like a low cadmium concentration, a neutral pH and a higher adsorbent dosage are adhere too. While glyphosate removal, a pH of 5 and higher ionic strength of KNO3. is required.

Surface charge characteristics and lime requirements of soils derived from basaltic, granite and metamorphic rocks in high rainfall tropical Queensland

Soil Research ◽  
1986 ◽  
Vol 24 (2) ◽  
pp. 173 ◽  
Author(s):  
GP Gillman ◽  
EA Sumpter
Keyword(s):  
Cation Exchange ◽  
Surface Charge ◽  
Soil Ph ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Exchange Method ◽  
High Rainfall ◽  
Exchangeable Al ◽  
Basaltic Soils ◽  
Highly Weathered Soils

The cation and anion exchange capacities of a large number of soils formed on basaltic, granitic, and metamorphic parent materials in the high rainfall area (approximately 4000 mm) of tropical north Queensland have been examined. Aspects studied included the changes in CEC and AEC between pH 4 and pH 6, the relative amounts of permanent and variable charge over this pH range, and the lime requirements of these highly weathered soils. A distinction is made between the Total Cation Exchange Capacity (CECT), defined as the Ca + Al adsorbed, and the Basic Cation Exchange Capacity (CECB), which is the Ca adsorbed. At low pH, CECB may be much less than CECT. The CEC, increase with pH in the highly oxidic basaltic soils is largely due to changes in surface charge, while in the granitic and metamorphic soils, increasing occupation of exchange sites by Al as pH decreases is the factor responsible for the increase in CECB. A good estimation of CECB at soil pH is obtained with a previously described compulsive exchange method, and there is high correlation between CECT at soil pH and the Effective Cation Exchange Capacity (= Ca + Mg + K + Na + Al). The amount of lime required to raise soil pH to pH 5.5 in the granitic and metamorphic soils was equivalent to the amount of exchangeable Al, but in the basaltic soils the lime requirement was two to three times greater than the amount of exchangeable Al.

scholarly journals Chemical attributes of a remineralized Oxisol

2017 ◽  
Vol 47 (11) ◽  
Author(s):  
Rafael Cipriano da Silva ◽  
Marina Elias Cury ◽  
João José Cardinali Ieda ◽  
Renata Alcarde Sermarini ◽  
Antonio Carlos de Azevedo
Keyword(s):  
Cation Exchange ◽  
Surface Charge ◽  
Cation Exchange Capacity ◽  
Amorphous Solids ◽  
Mechanisms Of Action ◽  
Exchange Capacity ◽  
Agricultural Fields ◽  
Chemical Attributes ◽  
Crystal Volume

ABSTRACT: Remineralizers are comminuted rocks that are applied to soil, and their use as an agricultural amendment was regulated in Brazil in 2013. However, mechanisms of action of these materials must be better known to enable them to be best used in agricultural fields. Soil chemical attributes of an Oxisol were monitored after the application of a diabase remineralizer. The increase in exchangeable Na observed was associated with the dissolution of the border of the plagioclase crystals where this element is highly concentrated (albite). Therefore, it was inferred that the time since the application of the remineralizer (1 to 2 years depending on the treatment) was not sufficient to exhaust this crystal volume. Unfortunately, the presence of several sources of Ca-containing minerals in the remineralizer did not allow to infer if the calcic nuclei was dissolving. An increase in effective cation exchange capacity was observed without the concurrent increase in the pH of the soil. The two non-exclusive hypotheses proposed to explain this result were that an extra surface charge has originated on the surface of the newly precipitated oxidic phases and/or from the dissolution of the remineralizer grains. Rapid precipitation of amorphous solids (as measured by the increase in Alo and Feo) would also explain the lack of increase in exchangeable Fe and Al despite the large amount of Al2O3 (11.90%) and Fe2O3 (14.45%) in the remineralizer.

EVALUASI PERUBAHAN KUALITAS TANAH PADA LAHAN BEKAS PENAMBANGAN NIKEL DI PULAU GEBE

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Mardi Wibowo
Keyword(s):  
Organic Carbon ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Mining Activity ◽  
Evaluation Activity ◽  
Land Quality ◽  
Environment Quality

Since year 1977 until 2005, PT. ANTAM has been exploited nickel ore resources at Gebe Island – Center ofHalmahera District – North Maluku Province. Mining activity, beside give economically advantages also causedegradation of environment quality espicially land quality. Therefore, it need evaluation activity for change ofland quality at Gebe Island after mining activity.From chemical rehabilitation aspect, post mining land and rehabilitation land indacate very lack and lackfertility (base saturated 45,87 – 99,6%; cation exchange capacity 9,43 – 12,43%; Organic Carbon 1,12 –2,31%). From availability of nutrirnt element aspect, post mining land and rehabilitation land indicate verylack and lack fertility (nitrogen 0,1 – 1,19%). Base on that data, it can be concluded that land reclamationactivity not yet achieve standart condition of chemical land.Key words : land quality, post mining lan

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