𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Retention of metallic cations by lignites and humic acids

✍ Scribed by JoséV. Ibarra; Jesús Osácar; JoséMa Gavilán

Publisher
Elsevier Science
Year
1979
Tongue
English
Weight
369 KB
Volume
58
Category
Article
ISSN
0016-2361

No coin nor oath required. For personal study only.

✦ Synopsis

Adsorption of strontium, lead, uranium and thorium ions from their solutions by several Spanish lignites have been studied. Adsorption isotherms are adequately described by means of the Langmuir equation and can be characterized by two numerical constants: the sorption capacity of lignite, and the geochemical enrichment factor (GEF). Very high values of this GEF have been found for heavy metals. Humic acids were extracted from the lignites and their metal binding ability was determined as a function of pH. Higher pH favours metal retention, also higher atomic weight and valency. A role of humic substances in the retention and accumulation of metals in coals is suggested.

📜 SIMILAR VOLUMES

Separation and characterization of humic
Separation and characterization of humic acids and metal humates by electrophoretic methods
✍ Ulrich Keuth; Anette Leinenbach; Horst P. Beck; Prof. Dr. Horst Wagner 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 592 KB

## Abstract A modified buffer for the separation of humic acids (HA) by capillary zone electrophoresis (CZE) was studied. The addition of hydroxycarboxylic acids to borate buffer makes a more efficient separation of HA possible. Two sharp peaks are obtained. Preparative isolation of these two fract

Modeling the Acid–Base Properties and Me
Modeling the Acid–Base Properties and Metal Complexation of Humic Substances with the Stockholm Humic Model
✍ Jon Petter Gustafsson 📂 Article 📅 2001 🏛 Elsevier Science 🌐 English ⚖ 150 KB

To describe the binding of protons and metals to humic substances, the Stockholm Humic Model (SHM) has been developed. The model employs a discrete-site approach similar to that of Model V/VI, although it has another electrostatic submodel, based on the Basic Stern concept. An empirical set of equat

Transformation of fenuron induced by pho
Transformation of fenuron induced by photochemical excitation of humic acids
✍ Aguer, Jean-Pierre; Richard, Claire 📂 Article 📅 1996 🏛 John Wiley and Sons 🌐 English ⚖ 299 KB

When neutral solutions containing the herbicide 3-phenyl-1,ldimethylurea (fenuron) and a humic acid are irradiated at 365 nm, 3-(4-hydroxy-pheny1)-1,l-dimethylurea and three biphenyl products are formed as main products. The apparent quantum yield of fenuron disappearance is evaluated as 6.2 x 10-5m