Influence of Carbonates on the Surface Charge of a Natural Solid

Davranche, Mélanie; Beaufreton, Sandrine; Bollinger, Jean‐Claude

doi:10.1006/jcis.2002.8249

Cited by 7 publications

(3 citation statements)

References 20 publications

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“…Slight retardation of chloride (Table 2) was observed due to anion exchange processes. Anion exchange can occur because of the positively charged surfaces of calcite due to protonation reactions (Davranche et al, 2002). The retardation was more pronounced in the slow column because of the higher residence time.…”

Section: Resultsmentioning

confidence: 99%

Release of Polycyclic Aromatic Hydrocarbons, Dissolved Organic Carbon, and Suspended Matter from Disturbed NAPL‐Contaminated Gravelly Soil Material

Totsche

Jann

Kögel‐Knabner

2006

Vadose Zone Journal

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The fate of polycyclic aromatic hydrocarbons (PAH) is known to depend on the release and redistribution of dissolved organic carbon (DOC) and particles. We studied the release of PAH, DOC, and particles up to a size of 200 mm with column outflow experiments using gravelly soil material. The material was collected at an abandoned industrial tar-oil contaminated site. To detect rate-limited release, the experiments were performed at two different mean pore water velocities, while multiple flow-interrupts were imposed. Effluent was analyzed for DOC, pH, electrical conductivity, turbidity, and particles larger than ,0.7 mm after filtration. The 16 Environmental Protection Agency PAHs were analyzed in the filtrate and in the particle fraction. Upon onset of flow large initial effluent concentrations were found for DOC, particles, turbidity, and particle-associated PAHs. This so-called first-flush export levelled off after a few pore volumes had been exchanged. The release of DOC and PAH in the filtrate was strongly rate limited. Measured PAH concentrations differed markedly from those calculated by Raoult's law. Equilibrium dissolution seems to be of minor importance for the studied materials. Particle release as well as the release of particle-associated PAHs was dependent on the flow velocity. However, effluent concentrations decreased significantly during no-flow conditions due to sedimentation of larger particles. At the lower flow velocity, 33% of the total PAHs were found in the retentate (66% in the filtrate), while at the higher flow velocity the amount of particle-associated PAH increased to 42%. The comparison of the PAH pattern in the filtrate and the retentate suggests that PAH transport takes place predominantly in the form of small NAPL droplets or fragments. The strong correlation of DOC with the PAH in the filtrate implies a marked influence of DOC on PAH transport. From these findings we conclude that PAH release and transport at contaminated sites is affected by three processes, i.e., (i) first-flush export, (ii) detachment of particle-associated PAHs due to hydraulic mobilization and (iii) the rate-limited release of particles and particle/ colloid-associated PAHs.

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Section: Resultsmentioning

confidence: 99%

Release of Polycyclic Aromatic Hydrocarbons, Dissolved Organic Carbon, and Suspended Matter from Disturbed NAPL‐Contaminated Gravelly Soil Material

Totsche

Jann

Kögel‐Knabner

2006

Vadose Zone Journal

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“…These mechanisms, complex by essence, proceed mainly at a molecular level (Schulten and Leinweber 2000), hence hardly detectable by physical approach. The emergence of negative charges as a result of HCO 3 formation (Davranche et al 2003) as well as deprotonation process, strongly activates soil buffering characteristics refl ected by dynamic sorption and retention of various ions, heavy metals particularly (Düring et al 2003). All these mechamisms are strictly controlled by changes of pH induced by the presence of phyto-ashes.…”

Section: Buffering Potentials Versus Geochemical Sustainabilitymentioning

confidence: 99%

Archives of Environmental Protection

Diatta¹,

Grzebisz²,

Bzowski³

et al. 2019

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Nine phyto-ashes from the biomass combustion of birch (Betula), oak (Quercus), red oak (Quercus rubra), horbeam (Carpinus), pine (Pinus sylvestris), poplar (Populus), maple (Acer), oilseed rape straw (Brassica napus) and wheat straw (Triticum aestivum) were blended with a biogas digestate at 1:1 mass ratio to give nine organic-mineral soil improvers. The concept of the research was to outline an eco-friendly and low cost soil improver for remediating degraded lands. These (i.e. phyto-ashes, improvers and the biogas digestate) were applied (0, 5, 10, 20, 40 t•ha -1 ) to a soil metallurgically contaminated with Cu, Zn, Pb and Cd. Of several tested parameters, pH changes revealed that organic-mineral soil improvers may effi ciently replace (linear R 2 >0.90 **** , P<0.001) phyto-ashes in soil remedial goals. Buffering properties expressed by the cation exchange capacity (CEC) improved progressively: 29, 52, 71, 100% (phyto-ash treatments) and: 18, 37, 44, 73% (improvers treatments) for the rates 5, 10, 20, 40 t•ha -1 , respectively as referred to the control CEC. The Dynamic Remediation Effi ciency (DRE) indices for Cu, Zn, Pb, Cd revealed metal-specifi c geochemical reactions initiated by phyto-ashes, improvers and biogas digestate. The rates 5.0-10.0 t•ha -1 for phyto-ashes and about 20 t•ha -1 for improvers [1:1, i.e. Phyto-ash:Biogas digestate] are recommended. For biogas digestate, the rates 10-20 t•ha -1 were found more effi cient.

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“…According to Davranche et al (2003), carbonates in aqueous solution exhibit coordination reactions in which HC0 3 -seems to play the key role. In the case of the current study the following mechanisms should be expected:…”

Section: Competitive Metal Sorption and Alkaline Cation Displacementmentioning

confidence: 99%

Competitivity, selectivity, and heavy metals-induced alkaline cation displacement in soils

Diatta

Grzebisz

Wiatrowska

2004

Soil Science and Plant Nutrition

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The simultaneous incorporation of heavy metals into the soil is still a matter of great concern. Interaction (competitive sorption) between these metals and the soil solid phase may result in a deterioration of soil quality which relies basically on amounts of alkaline cations saturating soils sorptive complex. Results of this study indicate that Pb, Cu, Cd, and Zn have induced solution pH decreases which were more intensive at highest metal loading rates. Partition parameters (Kd)-based sequences showed that Pb and Cu were more competitive than Cd and Zn and the overall selectivity sequence followed: Pb > Cu > Cd > Zn.Metal loadings and their competitive sorption have led to a strengthened displacement of alkaline cations (Le. Ca 2 +, Mg2+, K+, Na+), especially of Ca 2 + as a factor "stabilizing" soil sorptive complex. Such metals impact jointly with soils acidification are of great environmental concern since tremendous amounts of alkaline cations (especially Ca 2 +) may be potentially leached out, irrespective of the degree of soil contamination, as evidenced in the current study. High and positive ..:1G values implied that the studied soils were characterized by generally low concentrations of exchangeable potassium which required high energy to get displaced (desorbed). Further studies on heavy metal uncontaminated or contaminated areas should be undertaken to provide with data which should be used for predictions on changes related to soil buffering capacity as impacted by heavy metal inputs.

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Influence of Carbonates on the Surface Charge of a Natural Solid

Cited by 7 publications

References 20 publications

Release of Polycyclic Aromatic Hydrocarbons, Dissolved Organic Carbon, and Suspended Matter from Disturbed NAPL‐Contaminated Gravelly Soil Material

Release of Polycyclic Aromatic Hydrocarbons, Dissolved Organic Carbon, and Suspended Matter from Disturbed NAPL‐Contaminated Gravelly Soil Material

Archives of Environmental Protection

Competitivity, selectivity, and heavy metals-induced alkaline cation displacement in soils

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