Data Mining for Source Apportionment of Trace Elements in Water and Solid Matrix

Trace elements migrate among different environment bodies with the natural geochemical reactions, and impacted by human industrial, agricultural, and civil activities. High load of trace elements in water, river and lake sediment, soil and air particle lead to potential to health of human being and ecological system. To control the impact on environment, source apportionment is a meaningful, and also a challenging task. Traditional methods to make source apportionment are usually based on geochemical techniques, or univariate analysis techniques. In recently years, the methods of multivariate analysis, and the related concepts data mining, machine learning, big data, are developing fast, which provide a novel route that combing the geochemical and data mining techniques together. These methods have been proved successful to deal with the source apportionment issue. In this chapter, the data mining methods used on this topic and implementations in recent years are reviewed. The basic method includes principal component analysis, factor analysis, clustering analysis, positive matrix fractionation, decision tree, Bayesian network, artificial neural network, etc. Source apportionment of trace elements in surface water, ground water, river and lake sediment, soil, air particles, dust are discussed.

New Methods in the Synthesis of (Meth)Acrylamides and Application Chelating Resin for Determination of Trace Metals in Certified Reference Materials and Waters

The waste of trace metals are led the pollutions of water, soil and air. That’s why the accurate and sensitive identification of amount of trace metals in food samples and environment are gained importance in analytical chemistry because of their toxicity to human health. Besides, the direct determination of trace metals, presented at very low concentration especially in real samples, is difficult. In this content, before determination of trace metals by instrumental methods can be achieved successfully using separation/preconcentration procedures. The different synthesized chelating polymer resin adsorbents are successfully used for the SPE of trace metals. The trace metals, such as Cu, Cr, Co, Mn, Zn and Fe, are necessary for human health, when it has been taken at certain limits. But, the trace metals, such as Hg, Cd, Pb, Ni and As are toxic metals for the human body. About this, there are studies on the determination of trace elements and mineral in food samples and environment. In this study, new methods in the synthesis of (meth)acrylamides and use as a sorbent in the trace metals extraction was identified.

Evaluation of Trace Elemental Levels as Pollution Indicators in an Abandoned Gold Mine Dump in Ekurhuleni Area, South Africa

In the Blesbokspruit area of Ekuhurleni, South Africa, previous gold mining activities resulted in many tailings dump sites. 20 representative soil samples were used in describing the distribution of metals. The soils were very strongly acidic ranging from 3.86 to 4.34 with a low cation exchange capacity (CEC). Based on X-ray fluorescence (XRF) analysis, elemental composition of the soils revealed average values of major elements such as Na2O (0.18%), MgO (0.63%), Al2O3 (6.51%), SiO2 (81.83%), P2O5 (0.04%), SO3 (3.40%), K2O (1.98%), CaO (0.45%), TiO2 (0.51%), Cr2O3 (0.17%), MnO (0.04%), Fe2O3 (3.59%), NiO (0.04%), As2O3 (0.02%), with Rb2O and SrO falling below 0.01%. Trace metals (TM) contamination levels in the soils were evaluated using various pollution indices which revealed that over 60% of the soils were between the high degree and the ultra-high degree of contamination classes. The concentration of various trace metals varies from 860.3–862.6 mg/kg for Cr; 324.9–328.4 mg/kg for Al; 200.9–203.4 mg/kg for As; 130.1–136.2 mg/kg for Fe; 121.9–125.8 mg/kg for Pb; 27.3–30.2 mg/kg for Co; 23.8–26.8 mg/kg for Ni; 7.2–9.2 mg/kg for Ti; 7.1–9.2 mg/kg for Cd; 4.0–5.6 mg/kg for Zn and 0.1–0.6 mg/kg for Cu.

Removal of Heavy Metals from Water and Wastewater Using Moringa oleifera

One of the contaminants in wastewater is the heavy metals. Treatment of heavy metals is of great importance because they can be harmful and dangerous for human being health. Conventional removal methods used include: ultrafiltration, reverse osmosis, ion exchange, solvent extraction, sedimentation, and chemical precipitation, and each method has some disadvantages besides high costs. In this chapter, Moringa oleifera cake residue, Moringa oleifera press cake, and Moringa oleifera leaves are introduced as a proposed alternative to replace conventional methods for heavy metal ions’ removal. The results of using Moringa oleifera cake residue showed that iron (Fe) was fully removed; copper (Cu) and cadmium (Cd) were successfully removed up to 98% and reduction of lead (Pb) of 82.17%. The heavy metals were successfully reduced using Moringa oleifera press cake. The removal percentage of iron, copper, and chromium reached 69.99%, 88.86%, and 93.73%, respectively. Moringa oleifera leaves were used to remove Cd (II) from synthetic water; the optimization was performed and each parameter was affecting the Cd (II) removal with different percentages, but pH was insignificant. As a conclusion, the Moringa oleifera seeds and leaves can be considered as a promising alternative in water treatment for heavy metal ions removal.

Use of Porous no Metallic Minerals to Remove Heavy Metals, Precious Metals and Rare Earths, by Cationic Exchange

This chapter is related with the preliminary study of some non-metallic minerals to evaluate their cationic exchange capacity, to remove heavy and precious metals, as well as rare earths elements. The minerals and materials used to execute the ion metals removal were bentonite, phosphorite, and diatomite. The chapter shows the physicochemical behavior of all these minerals, which were used to remove the mentioned elements from solutions coming from ore leaching. It was found that in all cases, the removal of heavy and precious metals, as well as rare earths elements reached over 90%. Although, there were minimal differences in efficiency for all minerals used (bentonite, phosphorite, and diatomite), it could be pointed that the phosphorite has the best results going from 99.43% of removal of Gd, to 99.95–100% for the case of Ce, Nd, La, Yb, Eu, Er, Sm, Tb, Ge, Pd, Pt, and Au.

Polyaniline-Based Nanocomposites for Environmental Remediation

With growth in civilisation and industrialisation, there is an increase in the release of toxic heavy metal ions and dyes into water system, which is of public concern. As a result, appropriate treatment methods have to be implemented in order to mitigate and prevent water pollution. The discovery of nanotechnology has led to the development and utilisation of various nanoadsorbent for the removal of pollutants from water. PANI nanostructures and nanocomposites are noble adsorbents that have gained popularity in addressing water pollution issues and have been reported in literature. In this chapter, the main focus is on the synthesis of PANI nanocomposites and nanostructures and their application as efficient adsorbents for water treatment. Detailed discussions on different synthetic routes and characterisation have been dedicated to applications of these materials and are compared for the adsorptive removal of heavy metal ions and dyes from water.

Low Dimensional Nanostructures: Measurement and Remediation Technologies Applied to Trace Heavy Metals in Water

A nanostructure is a system in which at least one external dimension is in the nanoscale, it means a length range smaller than 100 nm. Nanostructures can be natural or synthetic and determine the physicochemical properties of bulk materials. Due to their high surface area and surface reactivity, they can be an efficient alternative to remove contaminants from the environment, including heavy metals from water. Heavy metals like mercury (Hg), cadmium (Cd), arsenic (As), lead (Pb), and chromium (Cr) are highly poisonous and hazardous to human health due to their non-biodegradability and highly toxic properties, even at trace levels. Thus, efficient, low-cost, and environmentally friendly methodologies of removal are needed. These needs for removal require fast detection, quantification, and remediation to have heavy metal-free water. Nanostructures emerged as a powerful tool capable to detect, quantify, and remove these contaminants. This book chapter summarizes some examples of nanostructures that have been used on the detection, quantification, and remediation of heavy metals in water.

Superabsorbent Hydrogels for Heavy Metal Removal

The superabsorbent hydrogels (SAHs) are 3D polymer networks having hydrophilic nature, which can swell, absorb, and hold incredible amount of water in aqueous medium showing better sorption ability. The sorption ability enables SAH to absorb organic pollutants, dyes, and heavy metal ions (HMI) from wastewater. Therefore, SAHs have recently got considerable interest from the researchers to be used for wastewater treatment. In order to know the swelling property and to understand the wastewater treatment in general and heavy metal ion removal from industrial effluent in particular, this chapter describes the removal of heavy metal ions from wastewater in details. Thus this chapter will enable us to understand the theoretical and experimental part regarding the removal of heavy metal ions by SAH from wastewater. It also highlights the parameters of adsorption process such as effect of initial concentration of heavy metal ions, effect of external stimuli (pH), effect of temperature on the removal of heavy metal ions, and dosage studies. The synthesis of SAH and its use for removal of heavy metal ions from wastewater as well as recycling, selectivity, and effectiveness are also discussed in detail.

Sustainable Treatment of Heavy Metals by Adsorption on Raw Chitin/Chitosan

The objective of this chapter was to treat metal pollution of wastewater rich in Pb2+, Cd2+, Cu2+, and Zn2+ ions by adsorption tests on the raw chitin/chitosan. Different origin namely shrimp (Ccre), crab (Ccra) and lobster (Clan). Raw shrimp chitin had a strong affinity for Pb2+ and Cd2+. The adsorption capacity of zinc on the crabs chitin is twice as great as that on the shrimp chitin. The kinetic study showed that more than 50% of these ions are adsorbed before equilibrium is reached (20 minutes). The adsorption kinetics also showed that the hardness of the shells has a negative effect on the kinetics of the adsorption process. Indeed, the adsorption of Pb2+ on the raw chitin shrimp requires only 30 minutes, while on the raw chitin lobster; the equilibrium time is 60 minutes. To ensure a sustainable treatment, sludge generated by adsorption of heavy metals was incinerated at high temperature. Incineration has led to calcite phases, which do not represent any toxicity on the environment and it can be recycled in the industry of solid materials (ceramics, cement, etc.). However, the regeneration of sludge by the acid changes the structure of the material and gives new adsorbent supports.

Mobility of Trace Element Contaminants from Abandoned Gold Mine Dump to Stream Waters in an Agricultural Active Area

In this study, the selected streams within the Blesbokspruit located in South Africa were characterised in this study. Because of prolonged mining activities coupled with ineffective management practices, several mine tailing (MT) dumps are widely distributed in this area. Metals and metalloid contamination from these tailing facilities have been reported to be major contributors to environmental hazards such as acid mine drainage (AMD). With increased agricultural activities in this area, an assessment of the general quality of water being utilised for irrigation purposes and feeding of farm animals becomes inevitable. A procedural method was implemented in a bid to identify relations between tailing and stream water contamination. Representative gold tailing sediments and water samples were collected, respectively. With the aid of X-ray fluorescence (XRF) and X-ray diffraction (XRD), the mineralogical characterisation of the tailing sediments was successfully carried out, while acid digestion using inductively coupled plasma-optical emission spectrometry (ICP-OES) was utilised in the determination of trace metal contents. Samples of different water sources were also characterised. There was a clear description of the link between tailings, water contamination and possible implications to animals and humans in the long run.