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1. Sorption of cationic organic substances onto synthetic oxides: Evaluation of sorbent parameters as possible predictors

Author:
Schaffer, Mario,   et al.   ; Kutzner, Susann; Licha, Tobias; Worch, Eckhard; Börnick, Hilmar;     Show all 5 Authors
Source:
The Science of the total environment 2018 v.643 pp. 632-639
ISSN:
0048-9697
Subject:
aluminum oxide; cations; chemical structure; ion exchange; models; organic matter; prediction; risk assessment; silica gel; sodium chloride; sorbents; sorption
Abstract:
... Knowledge on the sorption behavior of cationic organic substances in aquatic systems is vital for their risk assessment due to the increasing detection of such chemicals in the hydrosphere. Their sorption behavior is strongly influenced by sorption processes onto mineral surfaces (e.g., oxides, clays). To contribute to the development of prediction tools, the impact of sorbent characteristics on t ...
DOI:
10.1016/j.scitotenv.2018.05.393

2. A framework for assessing the retardation of organic molecules in groundwater: Implications of the species distribution for the sorption-influenced transport

Author:
Schaffer, Mario,   et al.   ; Licha, Tobias;     Show all 2 Author
Source:
The Science of the total environment 2015 v.524-525 pp. 187-194
ISSN:
0048-9697
Subject:
aquatic environment; aquifers; biogeography; chemical speciation; groundwater; organic compounds; pH; prediction; solutes; sorption
Abstract:
... The pH-dependent molecule speciation (charge state) in solution strongly influences the transport of ionizable organic compounds in the aquatic environment. Therefore, the sorption behavior is complex and reliable predictions only based on physico-chemical sorbate, sorbent and solution properties are challenging. A short overview of underlying sorption processes causing retardation during the solu ...
DOI:
10.1016/j.scitotenv.2015.04.006

3. Preservation of commonly applied fluorescent tracers in complex water samples

Author:
Schaffer, Mario,   et al.   ; Cao, Viet; Jin, Yulan; Licha, Tobias;     Show all 4 Authors
Source:
Grundwasser 2017 v.22 no.2 pp. 127-133
ISSN:
1430-483X
Subject:
calcium; centrifugation; fluorescence; iron; pH; tracer techniques
Abstract:
... Water sample preservation and pre-treatment are important steps for achieving accurate and reproductive results from tracer tests. However, this is particularly challenging for complex water mixtures prior to fluorescence analysis. In this study, the interference of iron and calcium precipitation with nine commonly applied conservative tracers, uranine, eosin, 1‑naphthalene sulfonate, 1,5-naphthal ...
DOI:
10.1007/s00767-017-0356-1

4. A guideline for the identification of environmentally relevant, ionizable organic molecule species

Author:
Schaffer, Mario,   et al.   ; Licha, Tobias;     Show all 2 Author
Source:
Chemosphere 2014 v.103 pp. 12-25
ISSN:
0045-6535
Subject:
aquatic environment; dissociation; guidelines; organic compounds; pH
Abstract:
... An increasing number of organic compounds detected today in the aquatic environment are ionizable and, therefore, partially or permanently charged (ionic) under the pH conditions encountered in these systems. For evaluating their environmental behavior, which strongly depends on the charge state, the identification of functional groups together with their correct assignment of the respective acidi ...
DOI:
10.1016/j.chemosphere.2013.12.009

5. Organic molecules as sorbing tracers for the assessment of surface areas in consolidated aquifer systems

Author:
Schaffer, Mario,   et al.   ; Warner, Wiebke; Kutzner, Susann; Börnick, Hilmar; Worch, Eckhard; Licha, Tobias;     Show all 6 Authors
Source:
Journal of hydrology 2017
ISSN:
0022-1694
Subject:
aquifers; cations; chemical structure; fluorescence; heat transfer; inorganic ions; organic compounds; salinity; sorption; surface area; temperature; tracer techniques
Abstract:
... Based on the assumption that the specific surface area to volume ratio Asurf/V of consolidated rock materials is proportional to the surface area available for sorption, several inorganic cations were recently proposed as sorbing (cation exchanging) tracers for estimating these ratios in aquifers (e.g., for deriving the efficient heat exchange area of geothermal reservoirs). The main disadvantages ...
DOI:
10.1016/j.jhydrol.2017.01.013

6. Sorption of organic cations onto silica surfaces over a wide concentration range of competing electrolytes

Author:
Schaffer, Mario,   et al.   ; Kutzner, Susann; Licha, Tobias; Worch, Eckhard; Börnick, Hilmar;     Show all 5 Authors
Source:
Journal of Colloid And Interface Science 2016 v.484 pp. 229-236
ISSN:
0021-9797
Subject:
sediments; sorbates; drugs; sorption; models; cations; cation exchange; aquatic environment; aquifers; adsorbents; sorption isotherms; silica gel; ionic strength; prediction; inorganic ions
Abstract:
... The fundamental understanding of organic cation-solid phase interactions is essential for improved predictions of the transport and ultimate environmental fates of widely used substances (e.g., pharmaceutical compounds) in the aquatic environment. We report sorption experiments of two cationic model compounds using two silica gels and a natural aquifer sediment. The sorbents were extensively chara ...
DOI:
10.1016/j.jcis.2016.08.029

7. Sorption of the organic cation metoprolol on silica gel from its aqueous solution considering the competition of inorganic cations

Author:
Schaffer, Mario,   et al.   ; Kutzner, Susann; Börnick, Hilmar; Licha, Tobias; Worch, Eckhard;     Show all 5 Authors
Source:
Water research 2014 v.54 pp. 273-283
ISSN:
0043-1354
Subject:
ammonium compounds; aqueous solutions; calcium; cation exchange; cations; magnesium; models; pH; silica gel; sodium; sorption; sorption isotherms; synthetic products
Abstract:
... Systematic batch experiments with the organic monovalent cation metoprolol as sorbate and the synthetic material silica gel as sorbent were conducted with the aim of characterizing the sorption of organic cations onto charged surfaces. Sorption isotherms for metoprolol (>99% protonated in the tested pH of around 6) in competition with mono- and divalent inorganic cations (Na+, NH4+, Ca2+, and Mg2+ ...
DOI:
10.1016/j.watres.2014.01.042

8. Influence of a compost layer on the attenuation of 28 selected organic micropollutants under realistic soil aquifer treatment conditions: Insights from a large scale column experiment

Author:
Schaffer, Mario,   et al.   ; Kröger, Kerrin Franziska; Nödler, Karsten; Ayora, Carlos; Carrera, Jesús; Hernández, Marta; Licha, Tobias;     Show all 7 Authors
Source:
Water research 2015 v.74 pp. 110-121
ISSN:
0043-1354
Subject:
aquifers; beta-adrenergic antagonists; biodegradability; cations; composts; denitrification; dissolved organic carbon; hydrophobicity; pollutants; redox potential; soil; sorption; sulfamethoxazole; wastewater treatment; water reuse
Abstract:
... Soil aquifer treatment is widely applied to improve the quality of treated wastewater in its reuse as alternative source of water. To gain a deeper understanding of the fate of thereby introduced organic micropollutants, the attenuation of 28 compounds was investigated in column experiments using two large scale column systems in duplicate. The influence of increasing proportions of solid organic ...
DOI:
10.1016/j.watres.2015.02.010

9. Role of cation exchange processes on the sorption influenced transport of cationic β-blockers in aquifer sediments

Author:
Schaffer, Mario,   et al.   ; Börnick, Hilmar; Nödler, Karsten; Licha, Tobias; Worch, Eckhard;     Show all 5 Authors
Source:
Water research 2012 v.46 no.17 pp. 5472-5482
ISSN:
0043-1354
Subject:
aquifers; beta-adrenergic antagonists; calcium; cation exchange; hydrophobicity; pH; prediction; sediments; sorption
Abstract:
... The influence of cation exchange processes on the transport behavior of the cationic β-blockers atenolol and metoprolol was investigated by applying saturated laboratory column experiments. Breakthrough curves using natural sediments under different competitive conditions were generated and resulting sorption coefficients were compared. For the cationic species of atenolol (at pH = 8), the existen ...
DOI:
10.1016/j.watres.2012.07.013
PubMed:
22884374

10. Sorption influenced transport of ionizable pharmaceuticals onto a natural sandy aquifer sediment at different pH

Author:
Schaffer, Mario,   et al.   ; Boxberger, Norman; Börnick, Hilmar; Licha, Tobias; Worch, Eckhard;     Show all 5 Authors
Source:
Chemosphere 2012 v.87 no.5 pp. 513-520
ISSN:
0045-6535
Subject:
aquifers; cation exchange; drugs; pH; sorption
Abstract:
... The pH-dependent transport of eight selected ionizable pharmaceuticals was investigated by using saturated column experiments. Seventy-eight different breakthrough curves on a natural sandy aquifer material were produced and compared for three different pH levels at otherwise constant conditions. The experimentally obtained KOC data were compared with calculated KOC values derived from two differe ...
DOI:
10.1016/j.chemosphere.2011.12.053
PubMed:
22230726

11. Influence of competing inorganic cations on the ion exchange equilibrium of the monovalent organic cation metoprolol on natural sediment

Author:
Schaffer, Mario,   et al.   ; Niedbala, Anne; Licha, Tobias; Nödler, Karsten; Börnick, Hilmar; Ruppert, Hans; Worch, Eckhard;     Show all 7 Authors
Source:
Chemosphere 2013 v.90 pp. 1945-1951
ISSN:
0045-6535
Subject:
sediments; freshwater; organic matter; sorption; calcium; ion exchange; models; cations; carbon; sodium; beta-adrenergic antagonists; prediction; inorganic ions
Abstract:
... The aim of this study was to systematically investigate the influence of the mono- and divalent inorganic ions Na+ and Ca2+ on the sorption behavior of the monovalent organic cation metoprolol on a natural sandy sediment at pH=7. Isotherms for the beta-blocker metoprolol were obtained by sediment–water batch tests over a wide concentration range (1–100000μgL−1). Concentrations of the competing ino ...
DOI:
10.1016/j.chemosphere.2012.10.036
PubMed:
23159068