Effects of humic acid on migration of montmorillonite and alumina colloid in a quartz sand column

A chemical fractionation scheme for soil boron was investigated by measuring the amounts of B extracted from minerals and synthetic soils amended with B. The scheme fractionated B into five fractions — readily soluble (solution plus non-specifically adsorbed), specifically adsorbed, oxide bound, organically bound and residual. These five fractions were extracted by 0.01 M CaCl2, 0.05 M KH2PO4, 0.2 M acidic NH4-oxalate, 0.02 M HNO3-30% H2O2, and 1:4:5 HNO3-HF-HCl, respectively. The methodology was tested on goethite and clay mica and three synthetic soils containing mixtures of goethite, clay mica, humic acid, calcite, and quartz sand and amended with three levels of B. Specifically adsorbed and oxide bound B were significantly correlated with the content of goethite in the synthetic soils, while residual B was significantly correlated with the content of clay mica. The recovery of extracted B, estimated as the percentage of total fractions over total B content in minerals and synthetic soils, ranged from 85 to 104%, with a mean of 97%. The overall results obtained with the fractionation scheme were deemed satisfactory as to sensitivity and precision for B fractionation. Key words: Boron, soil fractionation, sequential extraction

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Humic acid sorption onto a quartz sand surface: A kinetic study and insight into fractionation

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2008.05.031 ◽

2008 ◽

Vol 325 (1) ◽

pp. 93-100 ◽

Cited By ~ 30

Author(s):

Aurélien Pitois ◽

Liam G. Abrahamsen ◽

Peter I. Ivanov ◽

Nick D. Bryan

Keyword(s):

Humic Acid ◽

Kinetic Study ◽

Quartz Sand ◽

Sand Surface ◽

Insight Into

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Removal of hepatitis a virus (HAV), poliovirus and MS2 coliphage by coagulation and high rate filtration

Water Science & Technology ◽

10.2166/wst.1995.0561 ◽

1995 ◽

Vol 31 (5-6) ◽

pp. 63-68 ◽

Cited By ~ 11

Author(s):

A. Nasser ◽

D. Weinberg ◽

N. Dinoor ◽

B. Fattal ◽

A. Adin

Keyword(s):

Humic Acid ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Cationic Polyelectrolyte ◽

High Rate ◽

Sand Column ◽

Virus Removal ◽

Jar Test ◽

Pathogenic Viruses ◽

Operation Unit

Filtration is considered a mandatory operation unit for the production of pathogen free drinking water from surface sources. This study was undertaken to determine the removal efficiency of enteric pathogenic viruses (hepatitis A virus and poliovirus) by high rate filtration and to determine the suitability of F+bacteriophages as index for the removal of these pathogens. A jar test was used to determine the optimal flocculation dose to be used in the high rate filtration experiments. At an alum concentration of 30 mg/l, the greatest reduction was observed for HAV (88.4%) as compared with poliovirus 1 (47%) and turbidity (61%). Addition of 1 mg/l cationic polyelectrolyte improved the reduction of HAV to 98.3% by flocculation, while the removal of polio 1 and turbidity was not improved. The presence of humic acid at a concentration of 15.3 mg/l interfered with flocculation performance of HAV and turbidity, while the addition of the cationic polyelectrolyte reduced the interference appreciably. High rate filtration (20 m/hr) using a 100 cm long sand column, resulted in reduction of 99%, 93% and 80% of turbidity, MS2 and poliovirus 1, respectively. Addition of polyelectrolyte enhanced the removal of viruses and turbidity. In the presence of humic acid no virus removal was observed by high rate filtration, whereas turbidity removal was unaffected. The removal of MS2 was similar to that of HAV rather than poliovirus 1. High rate filtration was found efficient for the removal of pathogenic viruses and turbidity from surface water. Under all conditions tested the removal of turbidity was greater than that of viruses.

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