scholarly journals A method to determine silver partitioning and lability in soils

2014 ◽  
Vol 11 (1) ◽  
pp. 63 ◽  
Author(s):  
Lara Settimio ◽  
Mike J. McLaughlin ◽  
Jason K. Kirby ◽  
Kate A. Langdon
Keyword(s):  
Cation Exchange ◽  
Inductively Coupled Plasma ◽  
Solid Phase ◽  
Soil Analysis ◽  
Total Concentration ◽  
Cation Exchange Resin ◽  
Exchange Capacity ◽  
Isotopic Dilution ◽  
Dilution Method ◽  
Potential Toxicity

Environmental context Soils contaminated with silver can have detrimental environmental effects because of silver’s toxicity to a range of soil-dwelling organisms. The total concentration of silver in soil, however, is often not a good indicator of potential toxicity as it does not account for variations in bioavailability. We report a method for soil analysis that measures the amount of silver available for uptake by soil-dwelling organisms, and hence could provide data that better reflect potential toxicity. Abstract There is increasing potential for pollution of soils by silver because of an increased use of this metal in consumer and industrial products. Silver may undergo reactions with soil components that mitigate its availability and potential toxicity, so that the total concentration of this metal in soil is not a useful indicator of potential risk. We developed an isotopic dilution method to simultaneously measure the partitioning (Kd-value) and lability (E-value) of Ag in soils, using the 110mAg isotope. An equilibration solution containing 10mM Ca(NO3)2 was used along with a cation exchange resin to correct for possible interferences from non-isotopically exchangeable Ag associated with soil colloids in suspension (Er-value). The quantification limits for Kd and Er will depend on the amounts of radioisotope spiked and daily detection limits of inductively coupled plasma-mass spectrometry instrumentation but are typically >4000Lkg–1 and <0.92mgkg–1. Measurement of Kd values for Ag in a range of soils indicated strong partitioning to the solid phase is positively associated with soil cation-exchange capacity or total organic carbon and pH. The concentrations of labile Ag in soils geogenically enriched in Ag were not detectable indicating occlusion of the Ag within poorly soluble solid phases. Measurement of labile Ag in soils spiked with a soluble Ag salt and aged for 2 weeks indicated rapid conversion of soluble Ag into non-isotopically exchangeable forms, either irreversibly adsorbed or precipitated in the soil. These results indicate that measurement of labile Ag will be important to estimate toxicity risks to soil organisms or to predict bioaccumulation through the food chain.

Studies on Sodium lauryl sulphate supported Thorium(IV) phosphate: A New Surfactant supported Cation exchange resin, Useful in Water Purification

2021 ◽  
Vol 17 ◽  
Author(s):  
Amita Somya ◽  
Mamata Singh
Keyword(s):  
Ion Exchange ◽  
Cation Exchange ◽  
Water Purification ◽  
Sol Gel ◽  
Synthesis Method ◽  
Cation Exchange Resin ◽  
Exchange Capacity ◽  
Sodium Lauryl Sulphate ◽  
Infrared Study ◽  
Chemical Studies

Background: With increasing population and decreased quality of drinking water, there is a great demand for the development of new materials and methods that can find applications in the purification of water. This paper presents our small effort from pollution to solution by presenting the synthesis method of new sodium lauryl sulphate supported thorium(IV) phosphate, its characterization, and disquisition of analytical applications by executing some dual separations of calcium. Methods: Sodium lauryl sulphate thorium(IV) phosphate was synthesized by sol gel method. The synthesized exchanger was characterized by some physico-chemical studies like powdered X-ray diffraction, Scanning electron microscopy, Thermo gravimetric-differential thermal analysis, EDAX and Fourier transform-infrared study and was also checked for its competency towards the ion exchange processes and in analytical chemistry. Results: The prominent characteristic of Sodium lauryl sulphate supported Thorium(IV) phosphate has been its tremendously high ion exchange capacity for sodium ions (3.10 meq/g) which is almost two and half times more than the exchange capacity of Thorium(IV) phosphate (ThP), i.e., 1.3 meq/g. The material was resulted in fibrous sheet which is quite thermally, mechanically stable and poorly crystalline. The material has shown selectivity towards Ca2+ and Hg2+ ions. Conclusion: The synthesized cation exchange material has been found quite thermally stable, showing drastically high exchange capacity and selectivity towards Hg2+ and Ca2+ metal ions which might be because of the use of an anionic surfactant, sodium lauryl sulphate while synthesis of Th(IV) phosphate which has played a key role in enhancing the exchange capacity and adsorption of specific metals as well. Therefore, based on the results obtained, the above said materials can find applications in water purification processes and also, in environmental pollution control where removal of Hg2+ and Ca2+ is required.

Solid-Phase Refolding of Cyclodextrin Glycosyltransferase Adsorbed on Cation-Exchange Resin

2008 ◽  
Vol 20 (1) ◽  
pp. 277-283 ◽  
Author(s):  
Dae-Hyuk Kweon ◽  
Dae-Hee Lee ◽  
Nam-Soo Han ◽  
Jin-Ho Seo
Keyword(s):  
Cation Exchange ◽  
Exchange Resin ◽  
Solid Phase ◽  
Cation Exchange Resin ◽  
Cyclodextrin Glycosyltransferase

scholarly journals Land Suitability Classification for Current Land Use in Akkar Plain- Tartous Governorate

2018 ◽  
Vol 27 (2) ◽  
pp. 89-105
Author(s):  
Safwan A. Mohammed Safwan A. Mohammed
Keyword(s):  
Land Use ◽  
Cation Exchange ◽  
Soil Texture ◽  
Cation Exchange Capacity ◽  
Soil Analysis ◽  
Exchange Capacity ◽  
Land Suitability ◽  
Land Evaluation ◽  
Limiting Factors ◽  
Physical Factors

Land evaluation is one of the most important tools for integrated land use management for sustainable agricultural and land use planning. The aim of this study is to evaluate the land suitability for current land use in akkar plain- Tartous Governorate. Depending on the elevation and land use, nine soil profiles representing the main physiographic units have been chosen. Soil samples were collected for conducting some chemical and physical analyses such as: soil texture (sand%, silt% and clay%), the content of organic matter OM, Cation Exchange Capacity CEC (cmol(+)/kg -1clay). The results of the soil analysis showed that the soil texture was Clay, and the pH values were between 7.13-8.5. Furthermore, The cation exchange capacity were ranging from (12-33) (cmol(+)/kg -1clay). Results of land evaluation showed that the limiting factors either fertility factors such as high pH in the villages of Beit-kamouna, Majdaloun-albaher and Dier-hbash, or physical factors such as shallowness depth of soil. The study concluded that the suitability class ranged from S2 to N2, which emphasis the importance of reconsidering the type of land use in the study area.

scholarly journals The research of the possibility of using industrial effluents for the regeneration of Na-cation exchanger in the water treatment process

2020 ◽  
Vol 61 (2) ◽  
pp. 139-144
Author(s):  
Svetlana E. Pratskova ◽  
◽  
Aleksandr V. Kolesnikov ◽  
Alena O. Kuvaeva ◽  
Oksana U. Kuznetsova ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Water Treatment ◽  
Cation Exchange ◽  
Sodium Sulfate ◽  
Cation Exchanger ◽  
Exchange Resin ◽  
Cation Exchange Resin ◽  
Industrial Effluents ◽  
Exchange Capacity ◽  
Water Treatment Process

One of the main tasks of environmental protection enterprises is to reduce industrial effluents. Industrial effluents with a content of sodium chloride 24-25% and sodium sulfate 1.5-3.0% are formed at one of the plants. The high content of sodium chloride in the effluent allowed us to make an assumption about the possibility of their use in the regeneration of Na-cation exchanger in the process of water treatment for vapor-vapor cooling of operating metallurgical units. The aim of the work was to determine the feasibility of using industrial salt effluents in the water treatment process while ensuring optimal conditions for the operation of Na-cation exchanger. In the process of water treatment used the method of removing impurities from water - cationization. This method is applied to soften water and is of independent importance in the preparation of additional water for low pressure boilers and make-up water for heating networks, if the source water has low alkalinity. The object of the study is a strongly acidic cation exchanger in the Na-form (Purolite PPC-100Na) designed to soften process water. In the course of the regeneration of cation exchange resin with a sodium sulfate-containing salt solution, the concentration of the latter should be controlled - this is due to the high exchange capacity and the real danger of the formation of the gypsum layer. The volume of spent regeneration solution (OPP) will contain sparingly soluble calcium sulfate and soluble magnesium sulfate. Under certain conditions, most of the calcium sulfate can be separated from the ORP in the form of a suspension of a two-water compound and detached from the solution. Laboratory studies were conducted on the effect of a solution of NaCl salt (24-25%) with an admixture of sodium sulfate (1.5-3.0%) on the total and working exchange capacity of cation exchange resin. In order to reduce the salt background of the regenerated solution, studies were carried out on the use of a 10% NaCl salt solution with an admixture of sodium sulfate (1.5-3.0%) on the static, dynamic and full dynamic working exchange capacity of cation exchange resin (SOE, DOE and PDOE). We used the methods of alkalimetric and complexometric titration to control the capacity value of the cation. It was determined that the numerical values of the DOE and PDOE of the studied cation exchanger during its regeneration with a saline solution of sodium chloride with a content of 1.5-3.0% sodium sulfate vary in the range of 1.96-1.22 and 2.58-1.89 mEq/g dry resin, respectively.

scholarly journals Aflatoxin B1 adsorption by the natural aluminosilicates - concentrate of montmorillonite and zeolite

2016 ◽  
Vol 70 (5) ◽  
pp. 519-524 ◽  
Author(s):  
Marija Markovic ◽  
Aleksandra Dakovic ◽  
George Rottinghaus ◽  
Mirjana Stojanovic ◽  
Vera Dondur ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Aflatoxin B1 ◽  
Natural Zeolite ◽  
Cation Exchange Capacity ◽  
Active Sites ◽  
Solid Phase ◽  
Bentonite Clay ◽  
Exchange Capacity ◽  
Composition Determination

Aflatoxin B1 adsorption by the concentrate of bentonite clay - montmorillonite and the natural zeolite - clinoptilolite and was investigated at the initial toxin concentration 4 ppm, with different amonunts of solid phase in suspension (10, 5, 2 and 1 mg/10 mL) and different pH values - 3, 7 and 9. Results indicated that for both minerals, decreasing the amount of solid phase in suspension, decrease the amount of active sites relevant for adsorption of aflatoxin B1. Thus, for concentrate of montnorillonite, at the lowest level of solid phase in suspension (1 mg/10 mL), aflatoxin B1 adsorption indexes were 97% at pH 3, 88% at pH 7 and 82% at pH 9, while for the natural zeolite, adsorption of toxin was 9% at pH 3 and 7% at pH 7 and 9. Since inorganic cations in minerals are mainly responsible for aflatoxin B1 adsorption, even the natural zeolite - clinoptilite has much higher cation exchange capacity (the content of inorganic exchangeable cations) compared to the concentrate of montmorillonite, adsorption of aflatoxin B1 by this mineral is much lower. Comparing the molecular dimensions of aflatoxin B1 molecule with the dimension of channels of clinoptilolite and interlamellar space of montmorillonite it is obvious that this toxin is adsorbed only at the external surface of clinoptilolite while in the montmorillonite all active sites are equally available for its adsorption. Thus, the concentrate of montmorillonite posess by higher adsorption capacity for aflatoxin B1. Results presented in this paper confirmed the fact the differences in the structure of minerals led to their different efficiency for adsorption of aflatoxin B1. Mineralogical and chemical composition, determination of cation exchange capacity, etc., are very important parameters influencing the effectiveness of minerals as aflatoxin B1 adsorbents. [Projekat Ministarstva nauke Republike Srbije, br. 451-03-2802-IP Tip1/142, br. 172018 i br. 34013] <br><br><font color="red"><b> This article has been corrected. Link to the correction <u><a href="http://dx.doi.org/10.2298/HEMIND170208003E">10.2298/HEMIND170208003E</a><u></b></font>

scholarly journals Effect of microalgae application on soil algal species diversity, cation exchange capacity and organic matter after herbicide treatments

F1000Research ◽  
2014 ◽  
Vol 3 ◽  
pp. 281 ◽  
Author(s):  
Karin L. Hastings ◽  
Lauren E. Smith ◽  
Michael L Lindsey ◽  
Luke C. Blotsky ◽  
Gloria R. Downing ◽  
...  
Keyword(s):  
Organic Matter ◽  
Species Diversity ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Soil Analysis ◽  
Soil Microbial Communities ◽  
Exchange Capacity ◽  
Positive Effects ◽  
Morphological Criteria ◽  
Herbicide Treatments

Soil microalgae live on small communities that change structure depending on many factors. Some of these factors include soil pH, agricultural practices as well as pesticide and herbicide treatments.  The size and activity of these soil microbial communities is an indicator of health, quality and fertility necessary for sustainable agriculture.  Methods:A commercial proprietary suspension of microalgae GOgreen®was applied at different concentrations through a center pivot irrigation system to a crop of cultivated corn (Zea mays) during six months.  Experimental plots of 0.5 acres each were planted in four rows. Corn (34,000 plants/acre) was planted in May and harvested in November allowing each plot to be studied for 6 months. In addition, one plot was planted for a second year to study the effects of consecutive planting and harvesting on algae populations in the soil. Soil samples were collected at a depth of 6 inches. Microalgae species identification was based on morphological criteria. Soil analysis included organic matter content (OM), pH and cation exchange capacity (CEC).Results:Treatment with GOgreen®has significant and measurable positive effects on soil OM content, CEC, pH and microalgae species diversity.Conclusions:  It was demonstrated through this study that GOgreen®increased diatom numbers and microalgae species diversity showing a restorative effect on soil quality after herbicide treatment in heavily farmed soil. Additionally, GOgreen®lowers the pH in soils with a pH higher than 7.0 emerging as an economical alternative that is safe for humans and the environment.

scholarly journals Top-Down Synthesis of NaP Zeolite from Natural Zeolite for the Higher Removal Efficiency of Cs, Sr, and Ni

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 252
Author(s):  
Seokju Hong ◽  
Wooyong Um
Keyword(s):  
Cation Exchange ◽  
Removal Efficiency ◽  
Natural Zeolite ◽  
Cation Exchange Capacity ◽  
Solid Phase ◽  
Exchange Capacity ◽  
Order Kinetic ◽  
Top Down ◽  
Kinetic Experiment ◽  
Bet Analysis

A solid phase of natural zeolite was transformed to Na-zeolite P (NaP zeolite) by a “top-down approach” hydrothermal reaction using 3 M of NaOH solution in a 96 °C oven. Time-dependent X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), XRF, and scanning electron microscopy (SEM) analysis as well as kinetic, isotherm, and cation exchange capacity experiments were performed to understand the mechanism of mineral transition from natural zeolite to NaP zeolite. The XRD crystal peaks of the natural zeolite decreased (decrystallization phase) first, and then the NaP zeolite XRD crystal peaks increased gradually (recrystallization phase). From the XRF results, the dissolution rate of Si was slow in the recrystallization phase, while it was rapid in the decrystallization phase. The specific surface area measured by BET analysis was higher in NaP zeolite (95.95 m2/g) compared to that of natural zeolite (31.35 m2/g). Furthermore, pore structure analysis confirmed that NaP zeolites have more micropores than natural zeolite. In the kinetic experiment, the results showed that the natural zeolite and NaP zeolite were well matched with a pseudo-second-order kinetic model, and reached equilibrium within 24 h. The isotherm experiment results confirmed that both zeolites were well matched with the Langmuir isotherm, and the maximum removal capacity (Qmax) values of Sr and Ni were highly increased in NaP zeolite. In addition, the cation exchange capacity (CEC) experiment showed that NaP zeolite has an enhanced CEC of 310.89 cmol/kg compared to natural zeolite (CEC = 119.19 cmol/kg). In the actual batch sorption test, NaP zeolite (35.3 mg/g) still showed high Cs removal efficiency though it was slightly lower than the natural zeolite (39.0 mg/g). However, in case of Sr and Ni, NaP zeolite (27.9 and 27.8 mg/g, respectively) showed a much higher removal efficiency than natural zeolite (4.9 and 5.5 mg/g for Sr and Ni, respectively). This suggests that NaP zeolite, synthesized by a top-down desilication method, is more practical to remove mixed radionuclides from a waste solution.

The availability of potassium in soils to crops as measured by its release to a calcium-saturated cation exchange resin

1984 ◽  
Vol 103 (2) ◽  
pp. 265-275 ◽  
Author(s):  
K. W. T. Goulding
Keyword(s):  
Cation Exchange ◽  
Field Experiments ◽  
Exchange Resin ◽  
Soil Analysis ◽  
Spring Barley ◽  
Cation Exchange Resin ◽  
West Germany ◽  
Wheat Field ◽  
K Fertilizer ◽  
Resin Method

SUMMARYThe amounts and rates of release of the different categories of soil K were measured on 21 soils from field experiments in England, Wales and West Germany using a calcium saturated cation exchange resin. The soils contained various amounts of exchangeable, fixed and matrix K; some contained no fixed K at all. These amounts could be qualitatively related to the clay contents of the soils.Regression analyses of K removed at harvest by spring barley, winter wheat, field beans and sugar beet, grown in the field experiments, were made on the quantities measured by the Ca-resin method and on K exchangeable to M ammonium acetate (EK). The Ca-resin method proved a better predictor of K availability than EK for all four crops. A multiple regression of the amount and rate of release of exchangeable K, and the rate of release of fixed K, as measured by Ca-resin, gave the best correlation with K removed. The contribution of fixed K to the regression increased with the demand of the crop for K and with the length of time the crops had been grown without K fertilizer. For the cereals, fixed K appeared to be either completely available or unavailable depending on whether its rate of release exceeded a critical value characteristic of each crop.The Ca-resin method is probably the best method available for measuring K reserves. It is, perhaps, too laborious for routine soil analysis, but could be used to characterize the long-term K release properties of a soil.

scholarly journals Concentration of fifteen elements in herbaceous stems of Ephedra intermedia and influence of its growing soil

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Anli Liu ◽  
Siqi Li ◽  
Nana Cen ◽  
Fuying Mao ◽  
Ruixia Yang ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Mass Spectroscopy ◽  
Cation Exchange Capacity ◽  
Inductively Coupled Plasma ◽  
Mineral Nutrients ◽  
Exchange Capacity ◽  
Soil Factors ◽  
Inductively Coupled ◽  
Fe And Mn ◽  
Mineral Accumulation

Abstract Mineral nutrients play important roles in the growth and metabolism of Ephedra intermedia, and are affected by soil factors. Fifteen elements were measured from wild E. intermedia as well as their growing soils using inductively coupled plasma mass spectroscopy to investigate the influences and characteristics of herb elements. The pH, cation exchange capacity, humus and soil mechanical composition were also determined in rhizosphere soils. Results showed that E. intermedia stems contained high N, low P concentrations in macronutrients and high Fe in micronutrients, and enriched N, S, Cl, P and Sr from soils. The 15 herb elements were affected by one or more soil factors, and K, P, Zn, Fe and Mn were important soil elements that influenced the mineral accumulation of E. intermedia. This study was useful for the artificial cultivation of wild E. intermedia.

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