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2019 | Buch

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Commercial Surfactants for Remediation

Mobilization of Trace Metals from Estuarine Sediment and Bioavailability

verfasst von: Dr. Anu Singh Bisht

Verlag: Springer Singapore

Buchreihe : Advances in Geographical and Environmental Sciences

Enthalten in: Springer Professional "Wirtschaft+Technik" , Springer Professional "Technik"

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Über dieses Buch

This book demonstrates the benefits of using commercially available surfactants, or surface-active agents, for remediation of metal-contaminated soil and sediment. First the book offers theoretical reviews of commercially available surfactants, then it proceeds to a study of various available surfactants for the mobilization of metals. Surfactants representative of amphiphiles discovered in the digestive environment of sediment-ingesting organisms are used to examine the extent and rate of metal (Al, Fe, Cd, Cu, Mn, Ni, Pb, Sn, Zn) mobilization from contaminated estuarine sediment. Metals can cause harmful effects to the environment and organisms. It is difficult to treat contaminants that are often tightly bound to the extremely small size of the estuarine sediments.

The book also demonstrates the mechanisms of metal mobilization that appear to be related to complexation with monomers and adsorption to micelles of the anionic amphiphiles, and to the denudation of hydrophobic host phases or coatings on the sediment by micelles of both anionic and nonionic surfactants.

Readers obtain a better understanding of current commercial surfactants, their impact on the environment, and possible remediation. This transdisciplinary book contributes toward Sustainable Development Goals numbers 6 (Clean Water and Sanitation) and 13 (Climate Action) set by the United Nations and is useful for students and teachers of sediment studies, coastal studies, environmental sciences, hydrology, civil engineering, and policy sciences.

Inhaltsverzeichnis

Frontmatter

Chapter 1. Introduction

Abstract

Metals are important for the normal development of organisms but they need to be in there allowed limits but if they exceed their limits, they become toxic for organisms as they are non-biodegradable and it continues in the environment and bioaccumulates in the organisms. Metals enter in the sediment through natural and anthropogenic activities. Human activities that lead to sediment contaminations are improper industrial discharge, deforestation mining tailings, poor agricultural practices, waste disposal, urban run-off, and etc. Basically, it can be divided into point and nonpoint sources of pollution. Point source pollution comes from any particular source such as a pipe and ship. Nonpoint source pollution cannot be found because it originates from numerous diffuse sources such as rainfall moving over and through the ground. Contaminated sediment not only contains metals such as lead, mercury, cadmium but also contains a large variety of other contaminants such as ammonia, phosphorous polychlorinated biphenyls (PCBs), chlordane, DDT, oil, Polycyclic Aromatic Hydrocarbons (PAHs), chlorinated hydrocarbons, and etc. These contaminants found in sediments can cause human health problems through the food chain.

Anu Singh Bisht

Chapter 2. Bioavailability of Metals in Sediment

Abstract

Different types of contaminants such as metals, hydrocarbons, PCBs, pesticides, and etc. enter the sediment and then to the aquatic habitat. These contaminants are very high in the sediment due to which it is very harmful to our living organisms as it enters in their body when they eat sediments. The transfers from lower organisms to upper organisms through the food chain. Many studies have shown that the accumulation of heavy metals from sediment and water to living tissues of organisms. Especially, many fishes contain the high level of mercury in their body. These harmful contaminants have shown serious health issues such as skin cancer, the decline in reproductive rates, improper embryonic development or progeny with birth defects, and neurological disorder. On the other hand, total concentrations of sediment-bound contaminant processed by deposit-feeding polychaetes cannot be predicted by their bioavailability and toxicity, despite suitable helpful measures of metal contamination in sediments.

Anu Singh Bisht

Chapter 3. Solubilization of Metals in Invertebrate Guts

Abstract

The gut of the deposit feeder’s organisms is the composition of complex mixtures of organic compounds, hydrolytic enzymes, and the surfactant which these organisms use it for dissolving and consumption of nutrients from the sediments. The digestive fluids vary in color and with age of the organisms. Studies have been done to know the composition and purpose of the surfactants. In this regard, three endogenous digestives, complex mixtures of surfactant compounds have been isolated from the gut of Arenicola marina (Smoot et al. in Mar Ecol Prog Ser 258:161–169, 2003). The complex mixture of fluid is able to dissolve contaminants bound in the sediments along with the nutrients and then travels to the whole body of the organisms and contribute in the bioaccumulation of the metals in the deposit feeder’s organisms. Several studies show that the complex mixture of the surfactant and dissolve process depends on the several parameters which are discussed in the chapter.

Anu Singh Bisht

Chapter 4. Surfactants

Abstract

Surfactant molecules have both hydrophobic (repels water molecules) and hydrophilic (attracts water molecules) assemblies that form micelles in the solutions. There are different types of surfactant depending upon the charge present on the hydrophilic portion of the molecule. The molecules form well-ordered micelles at concentration called the critical micelle concentration (CMC). The surfactant has widely used as cleaners in several products in industries. It is a promising agent for the removal of different metals, other chemicals coming out from the industries or agriculture runoff, like chlorinated and hydrocarbons etc. that bound to the soils or sediment. The mechanism of the extraction of metals from the sediment has also been studied and found that surfactant primarily makes complexes with metals before it extracts it from sediment. The surfactant efficiency can be increased by adding other agents. The different surfactants have different capacities to extract the different percentage of metals from the sediment.

Anu Singh Bisht

Chapter 5. Commercial Surfactants for Remediation-Introduction

Abstract

Arenicola marina is an organism whose habitat is spread most of Europe and northeastern America. The gut of this organism is the mixture of surfactants, proteins, enzymes and other unidentified organic materials which plays an important role in the oxidation and recycling of sediment organic matter. Different types of surfactants such as Sodium dodecyl sulfate (SDS), Sodium taurocholate (NaTC), Hexadecyltrimethylammonium (HDTMA), Triton X 100 (TX 100), and Synthesized N-glycino 2,6-dimethylheptanamide has been used for this research to find out the possibility of surfactants for enhancing the release of metals from estuarine sediment while the other is to examine surfactants as a surrogate of gut fluid of invertebrates to determine their metal bioavailability. It is the largest estuary which empties into Plymouth Sound (Grabemann et al. 1997). The contaminated sediment has been collected from the Tamar estuary because it is contaminated by numerous point and non-point sources of discharge. The sediment of this estuary is contaminated by different metals.

Anu Singh Bisht

Chapter 6. Commercial Surfactants for Remediation-Methodology

Abstract

The sediment sample for the experiment was taken from the Tamar estuary which has been polluted by the mining and industrial discharge. Only less than 63-μm fraction of the sediment was used. The sample was properly filtered, digested and centrifuge for further experiments. Five different types of surfactants have been used for the experiment, four were the commercial surfactant and one was synthesized in the laboratory that mimics the digestive fluid found in the deposit feeders like Arenicola Marina. These different type of surfactants are Hexadecyltrimethylammonium (HDTMA-Br) cationic, Sodium Dodecyl Sulfate (SDS) ≥ 9% anionic, Taurocholic acid, Sodium salt hydrate ≥ 97% anionic, Triton X-100 (TX-100) non-ionic, and Synthesized N-glycino 2,6-dimethylheptanamide anionic. The samples were stored with the different surfactant at the different concentrations of surfactants. The sub-sample was collected at the different interval of time and their pH was measured. The collected sub-sample was centrifuge and kept it for further analysis.

Anu Singh Bisht

Chapter 7. Metal Analysis

Abstract

There are different techniques that provide precise measurement of the concentration of the different elements in the sample. For this research, inductively coupled plasma mass spectrometry (ICP-MS) for Mn, Zn, Pb, U, Hg, Ag, Sn, Cu, Cr, Co, As and inductively coupled plasma optical emission spectrometry (ICP-OES) for Al, Fe, Mn, Zn, Pb, Cu, U, and Ni were used to determine the concentration of metals in the sample because it has superior detection limit. The samples were in the liquid form and diluted before proceeding for experiments. The liquid sample first dissociated into ions with the help of argon plasma source. The instrument was calibrated time to time like, after every ten samples with the standards. Both the instruments have shown very low the limits of detection (LOD). The total concentration of carbon (C), hydrogen (H) and nitrogen (N) were measured and discussed in the sample collected from the Tamar estuary.

Anu Singh Bisht

Chapter 8. Metal Concentration

Abstract

The original <63 μm fraction of sediment sample collected from the Tamar estuary were analyzed by ICP-OES. With the help of ICP-OES, the total concentration of major elements and trace metals (Al, Fe, Mn, Cu, Pb, Zn, Sn, Cr, Co, and Cd) in the sediments were measured. The obtained data verify the variety of geochemical and contaminant characteristics of the sediment samples. There were the high concentrations of Fe and Al in the sediment. Mn, Zn, Pb, and Cu were around 200 micrograms per gram of sediment were present. The total percentage of Carbon, Nitrogen, and Hydrogen in the sample measured by C, H, N, analyzer. There were 3.8 % of Carbon, 0.35 % of Nitrogen and 0.85% of hydrogen were present in the sample. The value of C/N ratio around 11 represents both marine and terrestrial organic components in the sediment which is close to the value of this sample.

Anu Singh Bisht

Chapter 9. Kinetics of Metal Release by Surfactants

Abstract

The kinetic experiments were performed by the sediment sample collected from the Tamar estuary with the different surfactants, HDTMA, SDS, TX 100, NaTC, and Synthesized at the different concentrations. The experiments were performed in seawater and MQ water. Total 14 different types of metals were analyzed by ICP-OES and ICP-MS. The incubation periods of samples with different surfactants were varied from 0 to 22 h and the release of metals in solution also varies from the different surfactants. HDTMA cationic surfactants are very useful and efficient to block metal contamination inside the sediment as it has positive charge whereas anionic and non-ionic surfactants are able to release metals from the sediment because they make complexes with metal bound in sediments. As the concentrations increase up to CMC the release of metals in the solution also increases but above the CMC it becomes constant and starts decreases if the concentration further increases, which indicates metals re-adsorbs by the sediment sample.

Anu Singh Bisht

Chapter 10. Surfactant Availability of Metals

Abstract

The different concentration of the different metals removed after incubation with different surfactants is measured and compared. The results show that anionic and non-ionic surfactants like SDS, Triton X 100 and NATC are able to mobilize the metals from the sediment but cationic HDTMA surfactant is unable to mobilize the metals from the sediment because of the positive charge of surfactant bound to the sediment and blocked metals inside the sediment. SDS is the best surfactant as compared to the other surfactant and releases 14% for Ni; 11% for Cu and rest of the metals (Pb, Zn, Al, Fe, and Mn) ranges from 5 to 3%. This is because the metals bounded with the surface of sediments attracted towards the negative charge of anionic surfactant instead of sediment. Therefore, the complexation of metals with surfactant micelles take place and releases metals from the sediment. The detailed mechanism of metal release is discussed in the chapter.

Anu Singh Bisht

Chapter 11. Implication of Surfactants in Remediation

Abstract

The current and previous studies elucidate that commercially available surfactants that mimic the natural constitutes of invertebrates gut fluids provide the efficient method for remediation of metals and organic pollutants from contaminated solids and waters. But, there are some disadvantages to the application of surfactants for remediation such as the formation of high-viscosity emulsions, toxic and very expensive. Surfactants found in the gut fluids of deposit feeders may play the different roles in their digestive system, for example, the dissolution of food particles. Mainly, there are two approaches either the metals are assimilated or not assimilated by organisms. If the metals are assimilated in the organisms, they may be become insoluble or accumulated in a specific organ or tissue and cause harmful effects. On the other hand, if not then metals pass through the complex gut fluids composition and enter into the aquatic environment where it may possible that it becomes more toxic to the environment.

Anu Singh Bisht

Chapter 12. General Discussion and Conclusions

Abstract

The removal of metals from the sediment by the use of the commercial available surfactants (SDS, HDTMA, NaTC, and Triton X 100) that mimic the gut fluid of deposit feeder’s invertebrates has been studied and results shows that the significant release of metals from sediments by surfactants. Occasionally, re-adsorption of metals has also been seen in the presence of SDS surfactant for metals like Al, Zn, Mn, and Fe. HDTMA surfactant shows the immobilization of metals from the sediments. The obtained results shows that surfactants were able to mobilize a large number of metals bound to sediments in relative to MQW than the seawater. By comparing the release of metals occurred by different surfactants shows that a great number of metals are removed by BSA and SDS. SDS plays an important role as BSA in the gut of deposit feeders. Hence, this approach is a predictive tool for metal bioavailability.

Anu Singh Bisht

Chapter 13. Marine Conservation and Sustainable Development Goals

Abstract

The first thing we can do to keep our marine and estuaries free from pollution is to make sure that pollution should not be able to enter into the water bodies. For example waste coming from the industries and sewage treatment plant needs to be treated properly before letting it enter into the water streams. We can treat pollution by adopting eco-friendly and low-cost options such as microorganism and the application of nanomaterials. Similarly, agriculture runoff can be controlled by controlling the soil erosion, less soil erosion means fewer nutrients enter the water bodies and problem like algae bloom can be avoided easily for this we can grow more and more plants at the edge of the agriculture field. Use of bio-fertilizer in place of chemical fertilizer. Building powerful laws and policies in order to protect oceans, seas, estuaries and other water streams from getting pollution from different sources. Aware community by launching programs in the schools and society, and by showing advertisements on the television.

Anu Singh Bisht

Backmatter

Titel: Commercial Surfactants for Remediation
verfasst von: Dr. Anu Singh Bisht
Verlag: Springer Singapore
Electronic ISBN: 978-981-13-0221-3
Print ISBN: 978-981-13-0220-6
DOI: https://doi.org/10.1007/978-981-13-0221-3