Role of Fly Ash in the Removal of Organic Pollutants from Wastewater

2009 ◽  
Vol 23 (3) ◽  
pp. 1494-1511 ◽  
Author(s):  
M. Ahmaruzzaman
Keyword(s):  
Fly Ash ◽  
Organic Pollutants

The Correlation Pattern of Fly Ash Components: Chromium as a Potential Catalyst in the Thermal Formation of Chlorinated Aromatic Compounds

2004 ◽  
Vol 1 (1) ◽  
pp. 18 ◽  
Author(s):  
Tomas Öberg ◽  
Tomas Öhrström ◽  
Jan Bergström
Keyword(s):  
Fly Ash ◽  
Organic Pollutants ◽  
Aromatic Compounds ◽  
Catalytic Effect ◽  
Chlorinated Phenols ◽  
Correlation Pattern ◽  
Aromatic Molecules ◽  
Chemical Agents ◽  
Chlorinated Aromatic Compounds

Environmental Context.Harmful chlorinated aromatic molecules are often formed and released into the environment during incineration of municipal waste and other waste fuels. This is a problem that has been known since the 1970s, and while efforts are being made to reduce these emissions, these persistent organic pollutants are still subsequently released into the environment, with residues and emissions to the atmosphere. In an attempt to uncover the chemical agents responsible for the formation of these pollutants, this study reveals that chromium, a commonly encountered metal, could be an important factor. Abstract.Chlorinated aromatic compounds are unintentionally released from combustion sources into the environment. This thermal formation is catalyzed by fly ash components and much interest has been focussed on the role of copper. This study report results from a series of 16 full-scale trials with different fuel compositions. The correlation pattern of fly ash components seem to suggest that the catalytic effect may be due also to other metal oxychlorination catalysts. Chromium shows particularly strong and statistically significant correlations with many of the chlorinated phenols, benzenes, dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs).

Microbiological Detoxification of Hazardous Organic Contaminants: The Crucial Role of Substrate Interactions

1992 ◽  
Vol 25 (11) ◽  
pp. 403-410 ◽  
Author(s):  
B. E. Rittmann
Keyword(s):  
Organic Pollutants ◽  
Information Flow ◽  
Organic Contaminants ◽  
Crucial Role ◽  
Substrate Utilization ◽  
Energy Flows ◽  
Hazardous Pollutants ◽  
Primary Substrate ◽  
Substrate Types

Microbiological detoxification of hazardous organic pollutants is highly promising, but its reliable implementation requires a sophisticated understanding of several different substrate types and how they interact. This paper carefully defines the substrate types and explains how their interactions affect the bacteria's electron and energy flows, information flow, and degradative activity. For example, primary substrates, which are essential for growth and maintenance of the bacteria, also interact with degradation of specific hazardous pollutants by being inducers, inhibitors, and direct or indirect cosubstrates. The target contaminants, which often are secondary substrates, also have the interactive roles of self-inhibitor, inhibitor of primary-substrate utilization, inducer, and a part of an aggregate primary substrate.

Multiple interactions in riverine biofilms - surfactant adsorption, bacterial attachment and biodegradation

1995 ◽  
Vol 31 (1) ◽  
pp. 61-70 ◽  
Author(s):  
Graham F. White
Keyword(s):  
Organic Pollutants ◽  
Bacterial Attachment ◽  
Solid Surfaces ◽  
Sediment Surface ◽  
Liquid Interfaces ◽  
Polluted Soils ◽  
Biofilm Bacteria ◽  
The Impact ◽  
Multiple Interactions

Many organic pollutants, especially synthetic surfactants, adsorb onto solid surfaces in natural and engineered aquatic environments. Biofilm bacteria on such surfaces make major contributions to microbial heterotrophic activity and biodegradation of organic pollutants. This paper reviews evidence for multiple interactions between surfactants, biodegradative bacteria, and sediment-liquid interfaces. Biodegradable surfactants e.g. SDS, added to a river-water microcosm were rapidly adsorb to sediment surface and stimulated the indigenous bacteria to attach to the sediment particles. Recalcitrant surfactants and non-surfactant organic nutrients did not stimulate attachment Attachment of bacteria was maximal when biodegradation was fastest, and was reversed when biodegradation was complete. Dodecanol, the primary product of SDS-biodegradation, markedly stimulated attachment. When SDS was added to suspensions containing sediment and either known degraders or known non-degraders, only the degraders became attached, and attachment accelerated surfactant biodegradation to dodecanol. These cyclical cooperative interactions have implications for the design of biodegradability-tests, the impact of surfactant adjuvants on biodegradability of herbicides/pesticides formulated with surfactants, and the role of surfactants used to accelerate bioremediation of hydrocarbon-polluted soils.

The role of calcium in blended fly ash geopolymers

2014 ◽  
Vol 49 (17) ◽  
pp. 5922-5933 ◽  
Author(s):  
Gina M. Canfield ◽  
Jeffery Eichler ◽  
Kara Griffith ◽  
John D. Hearn
Keyword(s):  
Fly Ash

Prenatal exposure to persistent organic pollutants as a risk factor of offspring metabolic syndrome development during childhood

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Marlene Cervantes González
Keyword(s):  
Metabolic Syndrome ◽  
Organic Pollutants ◽  
Prenatal Exposure ◽  
Persistent Organic Pollutants ◽  
Animal Studies ◽  
Polychlorinated Biphenyl ◽  
Environmental Pollutants ◽  
Epidemiological Studies ◽  
Experimental Findings

Abstract Persistent Organic Pollutants (POPs) are exogenous, artificially made chemicals that can disrupt the biological system of individuals and animals. POPs encompass a variety of chemicals including, dioxins, organochlorines (OCs), polychlorinated biphenyl (PCBs), and perfluoroalkyl substances (PFASs) that contain a long half-life and highly resistant to biodegradation. These environmental pollutants accumulate over time in adipose tissues of living organisms and alter various insulin function-related genes. Childhood Metabolic Syndrome (MetS) consists of multiple cardiovascular risk factors, insulin function being one of them. Over the years, the incidence of the syndrome has increased dramatically. It is imperative to explore the role of persistent organic pollutants in the development of Childhood Metabolic Syndrome. Some epidemiological studies have reported an association between prenatal exposure to POPs and offspring MetS development throughout childhood. These findings have been replicated in animal studies in which these pollutants exercise negative health outcomes such as obesity and increased waist circumference. This review discusses the role of prenatal exposure to POPs among offspring who develop MetS in childhood, the latest research on the MetS concept, epidemiological and experimental findings on MetS, and the POPs modes of action. This literature review identified consistent research results on this topic. Even though the studies in this review had many strengths, one major weakness was the usage of different combinations of MetS criteria to measure the outcomes. These findings elucidate the urgent need to solidify the pediatric MetS definition. An accurate definition will permit scientists to measure the MetS as a health outcome properly and allow clinicians to diagnose pediatric MetS and provide individualized treatment appropriately.

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