Fluridone Adsorption on Mineral Clays, Organic Matter, and Modified Norfolk Soil

Weed Science ◽  
1983 ◽  
Vol 31 (4) ◽  
pp. 528-532 ◽  
Author(s):  
Patrick J. Shea ◽  
Jerome B. Weber
Keyword(s):  
Aqueous Solution ◽  
Organic Matter ◽  
Charge Transfer ◽  
Aqueous Solutions ◽  
Clay Minerals ◽  
Physical Adsorption ◽  
Van Der Waals ◽  
Adsorption And Desorption ◽  
Adsorption Mechanisms ◽  
Ph Dependent

Adsorption and desorption characteristics of fluridone (1-methyl-3-phenyl-5-[3-txifluoromethyl)phenyl]-4-(1H)-pyridinone} on prepared clays and organic matter were studied in unbuffered and buffered aqueous solutions. In unbuffered aqueous solution the adsorption of fluridone decreased in the order: H-saturated organic matter (H-OM) > Ca-saturated montmorillonite (Ca-mont) > Ca-saturated organic matter (Ca-OM) > kaolinite. Based on the chemistry of fluridone, the nature of the adsorbent, and previously reported studies, the major adsorption mechanisms appear to be pH-dependent adsorption of protonated fluridone and direct protonation of the herbicide at acidic surfaces, supplemented by physical adsorption forces such as van der Waals attractions and charge transfer bonds. The adsorption of fluridone on Norfolk sand (Typic Paleudult; fine-loamy, siliceous, thermic), unmodified (CK), or amended with montmorillonite (HC) or organic matter (HM) at pH 4.0, 5.2, and 7.0 was also studied. Over all adsorption was greatest on HC soil, least on CK soil, and intermediate on the HM soil. In each system adsorption was inversely related to pH. These results were interpreted by comparison with adsorption observed on prepared clay minerals and organic matter.

Rapid removal of caffeine in aqueous solutions by peroxymonosulfate oxidant activated with cobalt ion

2015 ◽  
Vol 72 (3) ◽  
pp. 478-483 ◽  
Author(s):  
Yunleiyu Guo ◽  
Tingting Shen ◽  
Chen Wang ◽  
Jing Sun ◽  
Xikui Wang
Keyword(s):  
Aqueous Solution ◽  
Organic Matter ◽  
Aqueous Solutions ◽  
Ph Value ◽  
Neutral Condition ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Negative Effects ◽  
Cobalt Ion ◽  
Rapid Removal

The removal of caffeine (CAF) in aqueous solution by peroxymonosulfate oxidant activated with cobalt ion was investigated under a variety of operating conditions. The effects of various operating parameters, such as oxone and Co2+ concentrations, pH value, and the coexistence of dissolved organic matter and inorganic anions on the removal of CAF have been investigated. The removal efficiency increased with the increase in the concentrations of oxone and Co2+ ion added. The additions of chloride, bicarbonate, and sodium humate have negative effects on the removal of CAF. Near-neutral condition (5.0 < pH < 7.0) is favorable for the removal of CAF. Based on our experiments, 100% degradation of 50 mg/L CAF can be achieved within 4 minutes under the conditions of 1.00 mM oxone and 0.10 mM Co2+ ion at pH 5.0–7.0.

Dependence of the Second Virial Coefficient of Aqueous Solutions of Small Non-Electrolytes on Partial Molar Volume and Molecular Weight of the Solutes

1993 ◽  
Vol 46 (6) ◽  
pp. 929 ◽  
Author(s):  
K Kiyosawa
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Aqueous Solutions ◽  
Molar Volume ◽  
Partial Molar Volume ◽  
Virial Coefficient ◽  
Van Der Waals ◽  
Second Virial Coefficient ◽  
Aqueous Systems ◽  
Quadratic Equations

The osmotic pressures of aqueous solutions of small non-electrolytes, namely ethane-1,2-diol, propane-1,2,3-triol, sucrose and raffinose , were found to be expressible by quadratic equations of the molar concentration, which indicate that these aqueous systems involve no term higher than the second virial coefficient A2. Analysis has shown that A2 mainly does not arise from non-ideality of the aqueous solutions, but its magnitude depends on the partial molar volume of the solute, more precisely on the molecular weight or van der Waals radius or volume of the solute in the aqueous solution.

scholarly journals Adsorption and desorption of three carbamate pesticides by illite, kaolinite and humic acid-clay complexes

2014 ◽  
Vol 10 (4) ◽  
pp. 2585-2591
Author(s):  
O. P. Bansal
Keyword(s):  
Organic Matter ◽  
Humic Acid ◽  
Clay Minerals ◽  
Clay Mineral ◽  
Organic Coatings ◽  
Adsorption And Desorption ◽  
Carbamate Pesticides ◽  
Saturated Clay ◽  
Pesticide Adsorption ◽  
Xrd Patterns

In soils organic matter and clay minerals are often so associated that it is not clear that how the presence of organic matter influences the sorptive process of clay minerals.  So, in order to factor and quantify component contributions of mineral fractions and humic acid phase to the sorption of pesticides on clay minerals, adsorption and desorption of three carbamate pesticides oxamyl (I), S-Ethyl-N-(methyl carbamoyl)-oxythio acetimidate (II) and N-Phenyl (ethyl cabamoyl) propylcarbamate (III) by Na+, Ca2+ saturated illite, kaolinite and humic acid-clay complexes were investigated by batch experiments. The adsorption was more on illite than kaolinite and followed the order pesticide III > I > II, adsorption on Na-saturated clay samples was more than Ca-saturated. The presence of humic acid enhances the pesticide adsorption. A composite model for estimating pesticide adsorption, which assumes mineral and organic matter fraction individually as adsorbent phases, predicted sorption within a factor of 0.75-1.4 times the measured value. The desorption data indicated that humic acid retains more pesticide than clay mineral. XRD patterns showed that humic acid is restricted to the external surfaces of clay tactoids, denoting that clay mineral fractions in soils including those with organic coatings play an important role in the retention of polar carbamate pesticides.

Clay mineral precipitation and transformation during burial diagenesis

1985 ◽  
Vol 315 (1531) ◽  
pp. 91-105 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Aqueous Solution ◽  
Organic Matter ◽  
Clay Minerals ◽  
Clay Mineral ◽  
Burial Depth ◽  
Burial Diagenesis ◽  
Mineral Precipitation ◽  
Water Ph ◽  
Trioctahedral Smectite

Detrital clay minerals alter systematically during burial diagenesis. Smectites evolve via intermediate ‘illite-smectites’ to illite. Trioctahedral ‘smectite-chlorites’ or ‘vermiculite-chlorites’ evolve towards true (polytype Ib) chlorites. In other reactions, authigenic clays (kaolinite, illite, chlorite) precipitate directly from aqueous solution rather than by continuous modification of some precursor lattice. In yet others, one mineral replaces another. Many of these reactions are influenced by organic matter and the various low molecular mass soluble products of its diagenetic and thermal maturation. Carbon dioxide and organic acids influence pore-water pH and this, in turn, affects the solubility of clay minerals. Trioctahedral phyllosilicates are particularly sensitive. In contrast, organic matter also acts as a reducing agent when iron (III) oxides are destabilized to produce Fe 2+ and a marked increase in alkalinity. This reaction stabilizes trioctahedral clays such as chamosite. The balance between these different reactions affects the course of clay mineral diagenesis and itself varies systematically with burial depth and temperature.

Particle Size Effects on Concentration of Metals in Lake Erie Bottom Sediments

1984 ◽  
Vol 19 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Alena Mudroch
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Clay Minerals ◽  
Surface Sediment ◽  
Size Effects ◽  
Lake Erie ◽  
Size Fraction ◽  
Mineralogical Composition ◽  
Major Elements ◽  
Sediment Samples

Abstract Surface sediment samples obtained at the offshore and nearshore area of Lake Erie were separated into eight different size fractions ranging from <2 µm to 250 µm. The concentration of major elements (Si, Al, Ca, Mg, K, Na, Fe, Mn and P), metals (Zn, Cu, Cr, Ni, V, Co and Pb) and organic matter was determined together with the mineralogical composition and morphology of the particles in each size fraction. The distribution of the metals in the offshore sediment was bimodal with the majority of the metals divided between the 63 to 250 um size fraction which also contained the highest concentration of organic matter (about 20%) and the <4 µm fraction containing up to 60% of clay minerals. However, the metals in the nearshore sediment were associated mainly with the clay minerals.

Comparison of the fixation of several metal ions onto a low-cost biopolymer

2002 ◽  
Vol 2 (5-6) ◽  
pp. 217-224 ◽  
Author(s):  
Z. Reddad ◽  
C. Gérente ◽  
Y. Andrès ◽  
P. Le Cloirec
Keyword(s):  
Aqueous Solutions ◽  
Metal Ions ◽  
Low Cost ◽  
Operating Conditions ◽  
Order Kinetic ◽  
Adsorption Mechanisms ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Beet Pulp ◽  
Removal Of Metal Ions

In the present work, sugar beet pulp, a common waste from the sugar refining industry, was studied in the removal of metal ions from aqueous solutions. The ability of this cheap biopolymer to sorb several metals namely Pb2+, Cu2+, Zn2+, Cd2+ and Ni2+ in aqueous solutions was investigated. The metal fixation capacities of the sorbent were determined according to operating conditions and the fixation mechanisms were identified. The biopolymer has shown high elimination rates and interesting metal fixation capacities. A pseudo-second-order kinetic model was tested to investigate the adsorption mechanisms. The kinetic parameters of the model were calculated and discussed. For 8 × 10-4 M initial metal concentration, the initial sorption rates (v0) ranged from 0.063 mmol.g-1.min-1 for Pb2+ to 0.275 mmol.g-1.min-1 for Ni2+ ions, with the order: Ni2+ > Cd2+ > Zn2+ > Cu2+ > Pb2+. The equilibrium data fitted well with the Langmuir model and showed the following affinity order of the material: Pb2+ > Cu2+ > Zn2+ > Cd2+ > Ni2+. Then, the kinetic and equilibrium parameters calculated qm and v0 were tentatively correlated to the properties of the metals. Finally, equilibrium experiments in multimetallic systems were performed to study the competition of the fixation of Pb2+, Zn2+ and Ni2+ cations. In all cases, the metal fixation onto the biopolymer was found to be favourable in multicomponent systems. Based on these results, it is demonstrated that this biosorbent represents a low-cost solution for the treatment of metal-polluted wastewaters.

Effect of thermal history of aqueous solutions of KCl on the metastable zone width

1984 ◽  
Vol 49 (3) ◽  
pp. 559-569 ◽  
Author(s):  
Jaroslav Nývlt
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Thermal History ◽  
Equilibrium Solubility ◽  
Metastable Zone Width ◽  
Zone Width ◽  
Preceding Experiment ◽  
History Of ◽  
Metastable Zone ◽  
The Given

The metastable zone width of an aqueous solution of KCI was measured as a function of the time and temperature of overheating above the equilibrium solubility temperature. It has been found that when the experiments follow close upon one another, the parameters of the preceding experiment affect the results of the experiment to follow.The results are interpreted in terms of hypotheses advanced in the literature to account for the effect of thermal history of solution. The plausibility and applicability of these hypotheses are assessed for the given cause of aqueous solution of a well soluble electrolyte.

scholarly journals I. Thermo-electric behaviour of aqueous solutions with mercurial electrodes

1879 ◽  
Vol 29 (196-199) ◽  
pp. 472-482 ◽  
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Internal Diameter ◽  
Thermo Electric ◽  
Thin Glass ◽  
Mercury Surface

In order to investigate this subject, I devised and constructed the following apparatus :—A and B are two thin glass basins, 81 millims. internal diameter (= 5,153 sq. millims. of mercury surface), and 6·0 centims. deep; each containing a layer of mercury about 1·0 centim. deep, covered by a layer, about 3 centims. deep, of the aqueous solution to be examined.

scholarly journals Meta-studtite stability in aqueous solutions. Impact of HCO3−, H2O2 and ionizing radiation on dissolution and speciation

2021 ◽  
Author(s):  
Junyi Li ◽  
Zoltán Szabó ◽  
Mats Jonsson
Keyword(s):  
Aqueous Solution ◽  
Ionizing Radiation ◽  
Aqueous Solutions ◽  
Carbonate Complexes ◽  
C Nmr

Four different uranyl-(peroxide)-carbonate complexes were identified during studtite and meta-studtite dissolution in aqueous solution containing 10 mM HCO3− by 13C NMR.

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