Cation exchange capacity of roots: Titration, sum of exchangeable cations, copper adsorption

Abstract To provide a measure of the total amount of exchangeable cations that can be held by peat expressed as mequiv./100 g air-dried peat, the modified method of Puustjärvi for cation exchange capacity has been proposed and studied collaboratively. The statistical treatment of the collaborators’ results indicate a satisfactory degree of precision and accuracy for the 3 products considered, moss, humus, and reed-sedge. The method for cation exchange capacity of peat materials, with the description of the transfer technique included, has been adopted as official first action. The 7 ASTM methods have been adopted as procedures.

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Simultaneous determination of the cation exchange capacity and the exchangeable cations on marl

Clay Minerals ◽

10.1180/claymin.1991.026.4.10 ◽

1991 ◽

Vol 26 (4) ◽

pp. 567-570 ◽

Cited By ~ 9

Author(s):

R. M. Cornell ◽

E. S. Aksoyoglu

Keyword(s):

Cation Exchange ◽

Simultaneous Determination ◽

Cation Exchange Capacity ◽

Exchange Capacity ◽

Exchangeable Cations

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Influence of clay minerals and exchangeable cations on the formation of humic-like substances (melanoidins) from D-glucose and L-tyrosine

Clay Minerals ◽

10.1180/000985599546271 ◽

1999 ◽

Vol 34 (3) ◽

pp. 487-497 ◽

Cited By ~ 12

Author(s):

P. Arfaioli ◽

O. L. Pantani ◽

M. Bosetto ◽

G. G. Ristori

Keyword(s):

Cation Exchange ◽

Clay Minerals ◽

Cation Exchange Capacity ◽

Exchange Capacity ◽

Exchangeable Cations ◽

Reaction Conditions ◽

Polymeric Compounds

AbstractThe ability to produce humic-like polymeric compounds, with D-glucose and L-tyrosine as starting materials, was evaluated in different mineral systems: (1) Ca-, Al- and Cu(II)-saturated montmorillonite; (2) Ca-, Al- and Cu(II)-saturated kaolinite; (3) quartz in the presence of two different amounts of the same cations (according to the cation exchange capacity of the clays); and (4) untreated quartz (as control). All systems proved to be effective in the formation of humic-like compounds, particularly quartz, in the presence of cations. The effectiveness in promoting humification reactions was strictly related to the amounts of added cations. In the reaction conditions considered, the humification appears to be due more to the cations than to the type of clay minerals. The clayey systems synthesized more complex (aromatic) substances than the quartz ones.

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Determination of cation exchange capacity of ryegrass roots by summing exchangeable cations

Plant and Soil ◽

10.1007/bf02214550 ◽

1989 ◽

Vol 116 (2) ◽

pp. 217-222 ◽

Cited By ~ 17

Author(s):

Z. Rengel ◽

D. L. Robinson

Keyword(s):

Cation Exchange ◽

Cation Exchange Capacity ◽

Exchange Capacity ◽

Exchangeable Cations

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Acid character of nontronite: permanent and pH-dependent charge components of cation exchange capacity

Clay Minerals ◽

10.1180/claymin.1972.009.4.07 ◽

1972 ◽

Vol 9 (4) ◽

pp. 425-433

Author(s):

B. S. Kapoor

Keyword(s):

Cation Exchange ◽

Cation Exchange Capacity ◽

Exchange Capacity ◽

Exchangeable Cations ◽

Dependent Component ◽

Ph Dependent ◽

The Difference ◽

The Cost ◽

Fe Ions ◽

Acid Character

AbstractThe cation exchange capacity (C.E.C.) of nontronite was determined by titrating the acid clay, prepared by the action of H-resin on nontronite, in water and some nonaqueous solvents. The base-titratable acidities of the acid nontronite, freshly prepared as well as aged, were found to be greater than the acidities extractable with 1 N NaCl; the difference was attributed to the non-exchangeable pH-dependent component of C.E.C. In the freshly prepared sample, H+ and Fe3+ ions were the only exchangeable cations. Ageing produced basic Fe ions which were exchangeable and whose amount increased at the cost of H− and Fe3+ ions. Whatever the age, the total quantity of these exchangeable cations corresponding to the total isomorphous charge, remained constant. The amount of the pH-dependent acidity also remained unchanged. A likely mechanism to account for the observed pH-dependent component of the C.E.C, of nontronite is suggested.

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