Cyclodextrin nanosponges in the removal of organic matter for ultrapure water in power generation

Abstract Sediment microbial fuel cells (SMFCs) are bio-electrochemical devices generating electricity from redox gradients occurring across the sediment–water interface. Sediment microbial carbon-capture cell (SMCC), a modified SMFC, uses algae grown in the overlying water of sediment and is considered as a promising system for power generation along with algal cultivation. In this study, the performance of SMCC and SMFC was evaluated in terms of power generation, dissolved oxygen variations, sediment organic matter removal and algal growth. SMCC gave a maximum power density of 22.19 mW/m2, which was 3.65 times higher than the SMFC operated under similar conditions. Sediment organic matter removal efficiencies of 77.6 ± 2.1% and 61.0 ± 1.3% were obtained in SMCC and SMFC, respectively. With presence of algae at the cathode, a maximum chemical oxygen demand and total nitrogen removal efficiencies of 63.3 ± 2.3% (8th day) and 81.6 ± 1.2% (10th day), respectively, were observed. The system appears to be favorable from a resources utilization perspective as it does not depend on external aeration or membranes and utilizes algae and organic matter present in sediment for power generation. Thus, SMCC has proven its applicability for installation in an existing oxidation pond for sediment remediation, algae growth, carbon conversion and power generation, simultaneously.

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Optimization of Operating Conditions for Maximizing Power Generation and Organic Matter Removal in Microbial Fuel Cell

Journal of Environmental Engineering ◽

10.1061/(asce)ee.1943-7870.0001179 ◽

2017 ◽

Vol 143 (4) ◽

pp. 04016090 ◽

Cited By ~ 9

Author(s):

Manaswini Behera ◽

M. M. Ghangrekar

Keyword(s):

Power Generation ◽

Organic Matter ◽

Fuel Cell ◽

Microbial Fuel Cell ◽

Operating Conditions ◽

Organic Matter Removal

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Lability of natural organic matter in freshwater: a simple method for detection using hydrogen peroxide as an indicator

10.5194/bg-2018-122 ◽

2018 ◽

Author(s):

Isabela Carreira Constantino ◽

Amanda Maria Tadini ◽

Marcelo Freitas Lima ◽

Lídia Maria de Almeida Plicas ◽

Altair Benedito Moreira ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Organic Matter ◽

Organic Carbon ◽

Natural Organic Matter ◽

Water Samples ◽

Ultrapure Water ◽

Model Compounds ◽

Simple Method ◽

The Difference ◽

One Year

Abstract. Natural organic matter (NOM) is an important component for understanding the behavior of pollutants in the environment. A fraction of NOM is considered labile, fresh and less oxidized. In this work, a simple method was developed to distinguish between labile (LOM) and recalcitrant (ROM) organic matter in freshwater samples. Pyruvate, lignin and fulvic acid were chosen as model compounds of labile and recalcitrant NOM. The samples were submitted to kinetic monitoring experiments using hydrogen peroxide. Pyruvate was the best standard for the quantification of LOM (for concetrations up to 2.9 mg L−1). ROM was quantified by measuring the difference between total organic carbon (TOC) and LOM concentrations. Curves obtained with 0.5 to 5.0 mg L−1 TOC (pyruvate) in freshwater or ultrapure water samples did not indicate the existence of a matrix effect. This simple method was applied to water samples that were collected monthly for one year; the resulting LOM concentrations ranged from 0.47 to 2.1 mg L−1 and the ROM concentrations ranged from 0.08 to 3.5 mg L−1. Based on this results we concluded that hydrogen peroxide kinetics can be used as a simple method to quantify LOM and ROM concentrations in freshwater samples.

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Influence of natural organic matter on equilibrium adsorption of neutral and charged pharmaceuticals onto activated carbon

Water Science & Technology ◽

10.2166/wst.2011.237 ◽

2011 ◽

Vol 63 (3) ◽

pp. 416-423 ◽

Cited By ~ 60

Author(s):

D. J. de Ridder ◽

A. R. D. Verliefde ◽

S. G. J. Heijman ◽

J. Q. J. C. Verberk ◽

L. C. Rietveld ◽

...

Keyword(s):

Organic Matter ◽

Activated Carbon ◽

Natural Organic Matter ◽

Limited Information ◽

Ultrapure Water ◽

Charge Effects ◽

Pore Blocking ◽

Pharmaceutical Removal ◽

Pharmaceutical Properties ◽

Positively Charged

Natural organic matter (NOM) can influence pharmaceutical adsorption onto granular activated carbon (GAC) by direct adsorption competition and pore blocking. However, in the literature there is limited information on which of these mechanisms is more important and how this is related to NOM and pharmaceutical properties. Adsorption batch experiments were carried out in ultrapure, waste- and surface water and fresh and NOM preloaded GAC was used. Twenty-one pharmaceuticals were selected with varying hydrophobicity and with neutral, negative or positive charge. The influence of NOM competition and pore blocking could not be separated. However, while reduction in surface area was similar for both preloaded GACs, up to 50% lower pharmaceutical removal was observed on wastewater preloaded GAC. This was attributed to higher hydrophobicity of wastewater NOM, indicating that NOM competition may influence pharmaceutical removal more than pore blocking. Preloaded GAC was negatively charged, which influenced removal of charged pharmaceuticals significantly. At a GAC dose of 6.7 mg/L, negatively charged pharmaceuticals were removed for 0–58%, while removal of positively charged pharmaceuticals was between 32–98%. Charge effects were more pronounced in ultrapure water, as it contained no ions to shield the surface charge. Solutes with higher log D could compete better with NOM, resulting in higher removal.

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