Polarity Dependence of Transport of Pharmaceuticals and Personal Care Products Through Birnessite-Coated Porous Media

Pharmaceuticals and personal care products (PPCPs) have drawn increasing concern of environmental health as they are continuously released into the environment. This study examined the effects of birnessite (δ-MnO2) on the transport and retention of five PPCPs in porous media under steady saturated flow conditions. Considering that natural birnessite occurs as discrete particles and small nodules, birnessite-coated sand was used to mimic the natural regime of birnessite in the environment. Batch isotherm experiments were conducted using uncoated and birnessite-coated sand; results showed that the difference in the affinity of the five PPCPs was correlated to their polarity characteristics. Column experiments were conducted by mixing 0, 10, and 20% birnessite-coated sands with the uncoated sands. These three percentages are equivalent to three contents of manganese (Mn) in the experimental columns (0, 55, and 109 μg Mn g−1 sand). Results suggested that polar compounds (such as bisphenol-A, tetracycline, and ciprofloxacin) had a higher affinity to birnessite-coated sands than the weak polar compounds (such as ibuprofen and carbamazepine) because the polarity was favorable to electrostatic attraction and oxidative reaction. Overall, birnessite decreased the mobility of polar PPCPs but exerted no significant effect on the mobility of weak polar PPCPs under continuous flow conditions. The polarity-based correlation extended traditional electrostatic theory while well interpreting the complicated effects of birnessite on the adsorption and transport of PPCPs, especially neutral or non-dissociated compounds like carbamazepine.

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Effects of Flow Regime on DOM Retention in Soils: Continuous Flow vs. Flow Interruption

10.5194/egusphere-egu2020-13629 ◽

2020 ◽

Author(s):

Jannis Florian Carstens ◽

Georg Guggenberger ◽

Jörg Bachmann

Keyword(s):

Continuous Flow ◽

Sessile Drop ◽

Contact Angles ◽

Transport Processes ◽

Solid Matrix ◽

Flow Conditions ◽

Oxide Mineral ◽

Flow Interruption ◽

Flow Stagnation ◽

Coated Sand

Dissolved organic matter (DOM) is one of the most mobile components of the global carbon cycle. Corresponding transport processes in the environment have received plenty of attention in the context of carbon sequestration as well as the mobility of DOM-associated contaminants.However, most previous transport studies have been conducted exclusively under continuous flow conditions, which are not comparable to real water flow characteristics in soil. The present study aims to address that gap in knowledge by systematically assessing the effect of defined flow interruption phases on the retention of DOM.For that, the breakthrough behavior of DOM as affected by phases of flow interruption was investigated in an increasingly complex system of solid matrices rich in oxide mineral coatings: goethite coated quartz sand, disturbed Cambisol subsoil, and undisturbed Cambisol subsoil. The classic DLVO and extended DLVO (XDLVO) models including Lewis acid&#8212;base parameters were applied based on measurements of sessile drop contact angles and zeta potentials. &#160;DOM retention was increasing with the duration of flow interruption, and retention was considerably higher in the soils than in goethite coated sand. After 112 hours of flow stagnation, DOM release from the soils was reduced to 16 to 22 % as compared to continuous flow conditions. The retention in the different solid matrix materials was well correlated with the respective amounts of oxalate and dithionite extractable oxide mineral phases. The DLVO model was capable of correctly predicting the mobility of DOM in goethite coated sand, but not in the soils, due to the fact that soil surface charge heterogeneities could not be measured. The XDVLO model predicted short-range hydrophilic repulsive interactions that may have contributed to the distinct tailing of the DOM breakthrough curves.We conclude that the significant DOM retention during phases of flow stagnation phases shows that more complex flow regimes need to be considered in order to assess the mobility of DOM in soils. In fact, many previous studies excluding phases of flow stagnation likely overestimated the mobility of DOM in the environment.

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Detachment of fullerene nC60 nanoparticles in saturated porous media under flow/stop-flow conditions: Column experiments and mechanistic explanations

Environmental Pollution ◽

10.1016/j.envpol.2016.03.053 ◽

2016 ◽

Vol 213 ◽

pp. 698-709 ◽

Cited By ~ 11

Author(s):

Zhan Wang ◽

Dengjun Wang ◽

Baoguo Li ◽

Jizhong Wang ◽

Tiantian Li ◽

...

Keyword(s):

Porous Media ◽

Column Experiments ◽

Saturated Porous Media ◽

Flow Conditions ◽

Mechanistic Explanations ◽

Stop Flow

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Concentration profiles of Personal Care Products in swimming pools

E3S Web of Conferences ◽

10.1051/e3sconf/20184400095 ◽

2018 ◽

Vol 44 ◽

pp. 00095

Author(s):

Anna Lempart ◽

Edyta Kudlek ◽

Mariusz Dudziak

Keyword(s):

Quantitative Analysis ◽

Personal Care Products ◽

Frequency Of Occurrence ◽

Concentration Profiles ◽

Swimming Pools ◽

Personal Care ◽

The Difference

Concentration profiles of Personal Care Products (PCPs) in outdoor and indoor swimming pools are compared. The difference in the obtained chromatographs were observed. The quantitative analysis show that the frequency of occurrence and concentrations of two selected compounds (BZ-3 and BZ-8) from PCPs are higher in indoor swimming pools than in outdoor swimming pools. The obtained in this work results for swimming pools located in Poland differ from those received in Spain in previous work.

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