Sorption and desorption of orthophosphate and pyrophosphate by mineral fractions of soils, goethite, and kaolinite

1991 ◽  
Vol 71 (3) ◽  
pp. 327-338 ◽  
Author(s):  
T. Al-Kanani ◽  
A. F. MacKenzie
Keyword(s):  
Ammonium Oxalate ◽  
Sorption Isotherms ◽  
Parent Material ◽  
Langmuir Equation ◽  
Particle Sizes ◽  
Sorption Data ◽  
Freundlich Equation ◽  
P Release ◽  
P Fertilizer ◽  
Degree Of Sorption

Sorption-desorption reactions of orthophosphate (OP) and pyrophosphate (PP) were studied in two size fractions of Quebec soils (St. Bernard and Dalhousie) and minerals (goethite and kaolinite). Soil and mineral samples were fractionated into two separates (20.0–2.0 μm and 2.0–0.2 μm). The soils had similar mineral suites, but the St. Bernard have more vermiculite, chlorite, and quartz in the coarser fraction than the Dalhousie soil, perhaps an indication of different origin of parent material. Soil and goethite samples sorbed more OP than PP whereas kaolinite sorbed small but similar amounts of PP and OP. The PP and OP sorption was found to be significantly correlated with acid ammonium oxalate extractable Fe, but not with dithionite extractable Fe. Kaolinite desorbed similar amounts of OP and PP whereas more OP than PP was desorbed from soil and goethite samples. The degree of subsequent desorption seemed to be related to degree of sorption. The lack of similarity between sorption and desorption isotherms may indicate that sorption isotherms are of limited value in P fertilizer studies especially with regard to the estimation of subsequent P release in fertilized soils. Smaller particle sizes and their larger specific surface area resulted in higher OP and PP sorption compared with the coarser particle sizes. For OP sorption, the Langmuir equation yielded the closest fit in comparison to Freundlich and Temkin equations; the Freundlich equation gave the closest fit for PP sorption data. The Langmuir equation failed to fit desorption data. Key words: Orthophosphate, pyrophosphate, sorption, desorption

scholarly journals Sorption capacity of phosphate in mineral soils: I Estimation of sorption capacity by means of sorption isotherms

1990 ◽  
Vol 62 (1) ◽  
pp. 1-8
Author(s):  
Raina Niskanen
Keyword(s):  
Ionic Strength ◽  
Sorption Capacity ◽  
Sorption Isotherms ◽  
Clay Content ◽  
Langmuir Equation ◽  
Soil Samples ◽  
Organic Carbon Content ◽  
Sorption Data ◽  
Mineral Soils ◽  
Extractable Al

The sorption capacity of phosphate in seven soil samples (clay content 1—70 %, organic carbon content 0.8—10.7 %, soil pH 4.2—5.3, oxalate-extractable Al 11—222 and Fe 11—202 mmol/kg soil) was studied by means of sorption isotherms. The soils were equilibrated, for two to seven days at +5 and +20°C, with solutions containing phosphate 0—10 mmol/l (0—200 mmol/kg soil) at a constant ionic strength of 0.01 . Prolongation of the reaction time increased the sorption of phosphate only partially. The rise in temperature, from +5 to +20°C, increased the sorption from higher phosphate concentrations. At +20°C, the sorption curves of three soils showed a sorption maximum of 4, 19 and 34 mmol/kg soil. The sorption data of six soils was in accordance with the Langmuir equation; the sorption maximum ranged from 15 to 119 mmol/kg soil, and were of the same magnitude as the maximums determined experimentally.

Extractable iron and aluminium predict the P sorption capacity of Thai soils

Soil Research ◽  
2005 ◽  
Vol 43 (6) ◽  
pp. 757 ◽  
Author(s):  
W. Wiriyakitnateekul ◽  
A. Suddhiprakarn ◽  
I. Kheuruenromne ◽  
R. J. Gilkes
Keyword(s):  
Sorption Capacity ◽  
Stepwise Regression ◽  
Clay Content ◽  
Langmuir Equation ◽  
Soil Types ◽  
Sorption Data ◽  
P Sorption ◽  
P Sorption Capacity ◽  
Freundlich Equation ◽  
Extractable Iron

The objective of this study was to determine if dithionite- and oxalate-extractable Fe and Al can be used to predict the P sorption capacity of Thai soils. Forty-five samples from diverse soil types were taken from surface and subsurface horizons of soils on sandstone, shale/limestone, granite, and basalt. The samples were analysed for P sorption, dithionite- and oxalate-extractable Fe and Al (Fed, Feo, Ald, Alo), specific surface area (SSA), and other soil properties. Generally P sorption data for these soils were slightly better fitted by the Langmuir equation than the Freundlich equation. The Langmuir P sorption maximum ranged from 35 to 1111 μg/g with a median value of 370 μg/g soil. Soils developed on basalt had higher values of P sorption maximum (xm) (range 400–1111 μg/g, median 597 μg/g) than soils on other parent materials. Fed concentrations in soils (4–74 g/kg) were much higher than Feo concentrations (0.2–13.8 g/kg) with values of Feo/Fed ranging from 0.01 to 0.28 (median 0.09), indicating that most of the free iron oxides were crystalline. Amounts of Ald and Alo were about equal with median values of 1.6 and 1.0 g/kg, respectively. About 80% of the samples had SSA values <40 m2/g. Both the P sorption maximum and Freundlich k were linearly related to SSA (R2 = 0.77, 0.74), Ald (R2 = 0.78, 0.79), Alo (R2 = 0.64, 0.74), Fed (R2 = 0.48, 0.41), Feo (R2 = 0.43, 0.72), and clay content (R2 = 0.48, 0.36). Stepwise regression indicated that 81% of the variability in P sorption by these soils could be explained by a combination of dithionite and oxalate Fe and Al, however, Ald alone is almost as effective in predicting the P sorption capacity of Thai soils.

Modeling time-dependent phosphate buffering capacity in different soils as affected by bicarbonate and silicate ions

Soil Research ◽  
2008 ◽  
Vol 46 (4) ◽  
pp. 315 ◽  
Author(s):  
Nirmal De ◽  
Samar Chandra Datta
Keyword(s):  
Control System ◽  
Sorption Isotherms ◽  
Buffering Capacity ◽  
Rate Of Change ◽  
Silicate System ◽  
Sorption Data ◽  
P Sorption ◽  
Freundlich Equation ◽  
Practical Implications ◽  
Different Soils

The aim of this paper was to establish a relationship between phosphate buffering capacity and time in the presence of specifically sorbed anions like bicarbonate and silicate. P sorption isotherms were obtained at different times of equilibration for 3 surface soil samples, namely, Typic Haplustept, Calcic Chromustert, and Ultic Paleustalf in 3 different systems namely, bicarbonate (0.001 m), silicate (0.001 m), and a control system without any bicarbonate or silicate and having a common concentration of 0.1 m NaCl. Phosphate sorption data at different times could be fitted very closely to a modified Freundlich equation of the form: X/m = KCntp, where X/m is the amount of phosphate sorbed at solution phosphate concentration C and time t in hours. The values of n and p were positive fractions (mostly) and found to vary with soils and ionic medium. The silicate system was more effective in decreasing P sorption. Phosphate buffering capacity, defined as the first-order partial derivative of X/m with respect to C, KntpCn–1, was calculated at a particular concentration of 0.3 mg/L (usual P concentration of soil solution) at different times from the optimised value of K, n, and p. Phosphate buffering capacity was maximum in the control system and found to increase with time. Bicarbonate and, particularly, silicate ion decreased buffering capacity drastically and also the rate of change of buffering capacity with time. The practical implications of this decrease in buffering capacity by bicarbonate and silicate ions is discussed.

scholarly journals Zn sorption on Ca-illite and Ca-smectite: experiment and modelling

2019 ◽  
Vol 98 ◽  
pp. 04008
Author(s):  
Christelle Latrille ◽  
Aubéry Wissocq ◽  
Catherine Beaucaire
Keyword(s):  
Ion Exchange ◽  
Clay Minerals ◽  
Sorption Isotherms ◽  
Ion Exchanger ◽  
Natural Environments ◽  
Sorption Site ◽  
Batch Experiments ◽  
Sorption Data ◽  
Relevant Role ◽  
Site Types

To predict Zn behaviour in soil, the retention properties of clay minerals plays a relevant role. In a continental environment, Ca is the main cation in solution. Soil reactivity may be reduced to sorption properties of Zn and Ca on illite and smectite, the major clay minerals in soil. With this assumption, a multi-site ion exchanger model has successfully been applied to the Zn sorption on Ca-illite and Ca-smectite. New batch experiments performed in this study enabled to collect sorption data for Zn on Ca-illite by concentration and pH isotherms. Zn sorption reversibility was then verified. These sorption data were modelled successfully with a multi-site ion exchanger (MSIE) formalism by using four sorption site types. Zn sorption isotherms on smectite were retrieved from literature and interpreted following the MSIE formalism. The obtained selectivity coefficients may be thereafter put into ion exchange models to describe the Zn sorption in natural environments.

Adsorption of Five Phenylurea Herbicides by Selected Soils of Czechoslovakia

Weed Science ◽  
1983 ◽  
Vol 31 (3) ◽  
pp. 368-372 ◽  
Author(s):  
Josef Kozak ◽  
Jerome B. Weber
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Properties ◽  
Adsorption Isotherms ◽  
Organic Matter Content ◽  
Matter Content ◽  
Langmuir Equation ◽  
Phenylurea Herbicides ◽  
Soil Organic Matter Content ◽  
Freundlich Equation

Adsorption of five phenylurea herbicides, metobromuron [3-(p-bromophenyl)-1-methoxy-1-methylurea], monolinuron [3-(p-chlorophenyl)-1-methoxyl-1-methylurea], linuron [3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea], chlorbromuron [3-(4-bromo-3-chlorophenyl)-1-methoxy-1-methylurea], and CGA-15646 [3-(3-chloro-4-methylphenyl)-1,1-dimethylurea] by eight selected soils of Czechoslovakia were studied. Constants from Freundlich and Langmuir equations were calculated and correlated with the major soil properties. Freundlich K values ranged from 1.84 to 128, and the Freundlich equation was better fitted to the adsorption isotherms than was the Langmuir equation. Soil organic-matter content was the most important factor influencing the range of adsorption.

scholarly journals Engineering Functionalized Chitosan-Based Sorbent Material: Characterization and Sorption of Toxic Elements

2019 ◽  
Vol 9 (23) ◽  
pp. 5138 ◽  
Author(s):  
Adnan Khan ◽  
Nisar Ali ◽  
Muhammad Bilal ◽  
Sumeet Malik ◽  
Syed Badshah ◽  
...  
Keyword(s):  
Experimental Data ◽  
Sorption Isotherms ◽  
Analytical Techniques ◽  
Aqueous Environment ◽  
X Ray Diffraction ◽  
Sorption Data ◽  
Regression Methods ◽  
Sorbent Material ◽  
Lead And Cadmium ◽  
Cadmium And Lead

The present study reports the engineering of functionalized chitosan (CH)-based biosorbent material. Herein, a two-step reaction was performed to chemically modify the CH using 1,4-bis(3-aminopropyl) piperazine to incorporate nitrogen basic centers for cations sorption from the aqueous environment. The resultant functionalized chitosan-based sorbent material was designated as CH-ANP and characterized using various analytical techniques, including elemental analysis, Fourier-transform infrared spectroscopy (FTIR), 13C NMR (in solid-state), X-ray diffraction, and thermal analysis. Then, the newly engineered CH-ANP was employed for the removal of copper, lead, and cadmium in the aqueous medium. Langmuir sorption isotherm analysis revealed that the highest sorption abilities achieved were 2.82, 1.96, and 1.60 mmol g−1 for copper, cadmium, and lead, respectively. Linear and nonlinear regression methods were deployed on the sorption data to study the behavior of the Langmuir, the Freundlich, and the Temkin sorption isotherms. Among the four different forms, the Langmuir isotherm type 1 fit well to the experimental data as compared to the other models. It also showed the lowest values of error, and a higher correlation coefficient than the Freundlich and Temkin models; thus it was the best fit with the experimental data compared to the latter two models. In conclusion, the findings suggest that chemically modified novel materials with enhanced Lewis basic centers are useful and promising candidates for the sorption of various toxic cations in aqueous solution.

scholarly journals New carbon from low cost vegetal precursors: acorn and cypress cone

2013 ◽  
Vol 11 (12) ◽  
pp. 2012-2021
Author(s):  
Giovanni Toscano ◽  
Giuseppe Cimino
Keyword(s):  
Methylene Blue ◽  
Low Cost ◽  
Chemical Properties ◽  
Sorption Isotherms ◽  
Surface Chemical ◽  
Sodium Dodecylbenzenesulfonate ◽  
Sorption Data ◽  
Treatment Changes ◽  
Mass Titration ◽  
Minor Extent

AbstractThermal-treated carbons from acorn and cypress cone were prepared and characterized. The uptakes of heavy metal ions (Ag+, Cd2+ and Cr+3) and organics (phenol, methylene blue and sodium dodecylbenzenesulfonate) from aqueous solution have been studied. Effects of activation by HCl and HNO3 acids on the sorption properties of these carbons were investigated by mass titration, sorption isotherms, IRS, SEM and XRS. The models of Langmuir and Freundlich do not represent our sorption data very well. An earlier proposed empirical correlation is applied successfully to carry out a parameter of comparison between the studied carbons. The acidic treatment changes the surface chemical properties of the two thermal-treated carbons lowering their sorption performances. The carbons show good capacities to uptake metals, phenol and methylene blue, but sodium dodecylbenzenesulfonate is removed from its solutions to minor extent. The up-taking properties are found similar to those of two worldwide used commercial grade carbons.

Phosphorus chemical changes under soils over a period of agricultural intensification

2020 ◽  
Author(s):  
Andrew Tweedie ◽  
Philip M. Haygarth ◽  
Anthony Edwards ◽  
Allan Lilly ◽  
Nikki Baggaley ◽  
...  
Keyword(s):  
Land Use ◽  
Agricultural Intensification ◽  
Agricultural Land ◽  
Ammonium Oxalate ◽  
Water Extraction ◽  
Nutrient Concentrations ◽  
Agricultural Land Use ◽  
Organic P ◽  
P Fertilizer ◽  
Over Time

&lt;p&gt;The use of phosphorus (P) fertilizer has been one of the defining contributors to productive agriculture since the green revolution during the middle of the last century. However, these increased yields have come at the cost of dependency upon the declining resources of P rock reserves and eutrophication of water bodies downstream. In this context, it is important to understand the long-term effects of these P fertilizer additions on soil chemistry over ~50 years in order explain past and current patterns in fertilizer usage and so to better inform future soil management.&lt;/p&gt;&lt;p&gt;We tested the hypothesis that phosphorus forms and availability in mixed use (arable and grazed) agricultural soil have changed over a period of 50 to 80 years of agricultural intensification. Spatially matched samples of soil from 34 agricultural sites in North East (NE) Scotland were collected at two timepoints. The first samples were taken between 1951 and 1981 and in all cases the resampling took place in the autumn of 2017. The soils sampled were representative of agricultural soils in NE Scotland.&lt;/p&gt;&lt;p&gt;The hypothesis was tested by employing a range of soil tests on the &amp;#8216;old&amp;#8217; and &amp;#8216;new&amp;#8217; time points.&amp;#160; These included water extraction for inorganic and organic P, nitrate and ammonium and dissolved organic carbon, acid ammonium oxalate extraction to investigate the soil P exchange complex and NaOH-EDTA extraction as a strong alkaline extractant which preserves organic P forms. Analysis by &lt;sup&gt;31&lt;/sup&gt;P NMR was conducted on the NaOH-EDTA extracts from 5 pairs of samples, to investigate the organic P chemistry of in greater detail.&lt;/p&gt;&lt;p&gt;Phosphorus concentrations for stronger extractants (NaOH-EDTA, acid ammonium oxalate) did not increase significantly (P&lt;0.05) over time. However, water extraction results showed increases in total P (P&lt;0.01) and inorganic P but decreases in organic P. Additionally, analysis by &lt;sup&gt;31&lt;/sup&gt;P NMR detected changes between timepoints in &amp;#945;-glycero-phosphate and pyrophosphate.&lt;/p&gt;&lt;p&gt;These results indicate that differences in the various chemical forms of P present in soil between the timepoints can be detected many decades apart. This indicates changes in the functioning of the P cycle in these soils under intensive agricultural land use over time. Knowledge of the P-cycling response of soils under agricultural land-use over decades provides an opportunity to understand changes in soil nutrient concentrations, balances and availability and inform studies seeking to improve the sustainable management of soil fertility.&lt;/p&gt;

scholarly journals Chemical dispersants and pre-treatments to determine clay in soils with different mineralogy

2011 ◽  
Vol 35 (5) ◽  
pp. 1589-1596 ◽  
Author(s):  
Cristiane Rodrigues ◽  
Virlei Álvaro de Oliveira ◽  
Pedro Marques da Silveira ◽  
Glenio Guimarães Santos
Keyword(s):  
Ammonium Oxalate ◽  
Clay Content ◽  
Mechanical Action ◽  
Coarse Sand ◽  
Lithium Hydroxide ◽  
Parent Material ◽  
Formation Processes ◽  
Soil Mineralogy ◽  
Chemical Dispersant ◽  
Pre Treatment

Knowledge of the soil physical properties, including the clay content, is of utmost importance for agriculture. The behavior of apparently similar soils can differ in intrinsic characteristics determined by different formation processes and nature of the parent material. The purpose of this study was to assess the efficacy of separate or combined pre-treatments, dispersion methods and chemical dispersant agents to determine clay in some soil classes, selected according to their mineralogy. Two Brazilian Oxisols, two Alfisols and one Mollisol with contrasting mineralogy were selected. Different treatments were applied: chemical substances as dispersants (lithium hydroxide, sodium hydroxide, and hexametaphosphate); pre-treatment with dithionite, ammonium oxalate, and hydrogen peroxide to eliminate organic matter; and coarse sand as abrasive and ultrasound, to test their mechanical action. The conclusion was drawn that different treatments must be applied to determine clay, in view of the soil mineralogy. Lithium hydroxide was not efficient to disperse low-CEC electropositive soils and very efficient in dispersing high-CEC electronegative soils. The use of coarse sand as an abrasive increased the clay content of all soils and in all treatments in which dispersion occurred, with or without the use of chemical dispersants. The efficiency of coarse sand is not the same for all soil classes.

scholarly journals Influence of the Nature of the Non-Framework Cations on the Sorption Properties of Natural Stilbite

1998 ◽  
Vol 16 (9) ◽  
pp. 715-731 ◽  
Author(s):  
M.W. Kasture ◽  
P.N. Joshi ◽  
V.V. Joshi ◽  
A.L. Choudhari ◽  
S.P. Mirajkar ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Water Sorption ◽  
Natural Zeolite ◽  
Sorption Isotherms ◽  
Chemical Affinity ◽  
Sorption Data ◽  
X Ray ◽  
First Time ◽  
Water Sorption Capacity ◽  
Water Sorption Isotherms

A natural zeolite of stilbite type, collected from the Deccan traps (Aurangabad, M.S., India), has been investigated for its selectivity sequence in exchanging extra-framework cations for the first time, using Ca2+, Sr2+, Ba2+, Mg2+, Na+ and Ag+ cations as the probe cations. The different cation-exchanged forms were characterised by X-ray powder diffraction, IR spectroscopy, TG/DTA, chemical analysis and water sorption capacity. Water sorption isotherms in the temperature range 303–393 K were obtained as a function of different non-framework cations up to a pressure of 22 Torr. The sorption data were analysed in terms of different sorption models. The characteristics and population of the non-framework cations were found to influence the chemical affinity for water sorbate almost in a similar trend.

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