Influence of Natural Organic Matter on As Transport and Retention

Prasesh Sharma, Massimo Rolle, Benjamin Kocar, Scott Fendorf, Andreas Kappler

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Natural organic matter (NOM) can affect the behavior of arsenic within surface and subsurface environments. We used batch and column experiments to determine the effect of peat humic acids (PHA), groundwater fulvic acids (GFA), and a soil organic matter (SUM) extract on As sorption/transport in ferrihydrite-coated sand columns. A reactive transport model was used to quantitatively interpret the transport of As in flow-through column (breakthrough) experiments. We found that As(III) breakthrough was faster than As(V) by up to 18% (with OM) and 14% (without OM). The most rapid breakthrough occurred in systems containing SUM and GFA. Dialysis and ultrafiltration of samples from breakthrough experiments showed that in OM-containing systems, As was transported mostly as free (noncomplexed) dissolved As but also as ternary As-Fe-OM colloids and dissolved complexes. In OM-free systems, As was transported in colloidal form or as a free ion. During desorption, more As(III) desorbed (23-37%) than As(V) (10-16%), and SUM resulted in the highest and OM-free systems the lowest amount of desorption. Overall, our experiments reveal that (i) NOM can enhance transport/mobilization of As, (ii) different fractions of NOM are capable of As mobilization, and (iii) freshly extracted SUM (from a forest soil) had greater impact on As transport than purified GFA/PHA.
Original languageEnglish
JournalEnvironmental Science & Technology (Washington)
Volume45
Issue number2
Pages (from-to)546-553
Number of pages8
ISSN0013-936X
DOIs
Publication statusPublished - 2011
Externally publishedYes

Keywords

  • Chemistry (all)
  • Environmental Chemistry
  • Breakthrough experiment
  • Coated sand
  • Column experiments
  • Ferrihydrites
  • Flowthrough
  • Forest soils
  • Fulvic acids
  • Natural organic matters
  • Peat humic acids
  • Reactive transport models
  • Soil organic matters
  • Subsurface environment
  • Arsenic
  • Biogeochemistry
  • Desorption
  • Dialysis
  • Experiments
  • Groundwater
  • Organic acids
  • Soils
  • Ultrafiltration
  • Biological materials
  • arsenic
  • ferric hydroxide
  • fulvic acid
  • ground water
  • humic acid
  • iron
  • natural organic matter
  • organic carbon
  • soil organic matter
  • breakthrough curve
  • desorption
  • element mobility
  • experimental study
  • extraction method
  • ferrihydrite
  • forest soil
  • mobilization
  • numerical model
  • organic matter
  • sand
  • sorption
  • ultrafiltration
  • adsorption
  • article
  • chemical analysis
  • colloid
  • concentration (parameters)
  • dialysis
  • extraction
  • process model
  • purification
  • sampling
  • surface property
  • transport kinetics
  • Adsorption
  • Benzopyrans
  • Ferric Compounds
  • Fresh Water
  • Kinetics
  • Models, Chemical
  • Silicon Dioxide
  • Soil
  • Soil Pollutants
  • Water Movements
  • Water Pollutants, Chemical
  • 39473-89-7 ferrihydrite
  • 7631-86-9 Silicon Dioxide
  • N712M78A8G Arsenic
  • XII14C5FXV fulvic acid
  • ENGINEERING,
  • ENVIRONMENTAL
  • SIZE-CLASS DISTRIBUTION
  • ARSENIC RETENTION
  • HUMIC ACIDS
  • IRON-OXIDE
  • ADSORPTION
  • GROUNDWATER
  • FERRIHYDRITE
  • MOBILIZATION
  • SEDIMENTS
  • SORPTION
  • arsenic 7440-38-2 pollutant, soil pollutant, water pollutant
  • arsenic(III) 22541-54-4 pollutant, soil pollutant, water pollutant
  • arsenic(V) 17428-41-0 pollutant, soil pollutant, water pollutant
  • fulvic acid 479-66-3
  • iron 7439-89-6
  • peat humic acid
  • 10069, Biochemistry studies - Minerals
  • 37015, Public health - Air, water and soil pollution
  • Equipment Apparatus Devices and Instrumentation
  • Pollution Assessment Control and Management
  • ORGANIC compounds
  • Research

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