Top Research Papers on Heavy Metals in Water

The review shows that the electrochemical detection of heavy metal ions is a very promising strategy that has attracted widespread attention and can be applied in agriculture, life science, clinical diagnosis, and analysis.

Nanotechnology finds its application almost in every field of science and technology. At the same time, it also helps to find the solution to various environment-related problems, especially water contamination. Nanomaterials have many advantages over conventional materials, such as high surface area, both polar and non-polar chemistries, controlled and size-tunable, easier biodegradation, which made them ideal candidates for water and environmental remediation as well. Herein, applications of non-carbon nanomaterials, such as layered double hydroxides, iron oxide magnetite nanoparticles, nano...

Natural occurrence and anthropogenic practices contribute to the release of pollutants, specifically heavy metals, in water over the years. Therefore, this leads to a demand of proper water treatment to minimize the harmful effects of the toxic heavy metals in water, so that a supply of clean water can be distributed into the environment or household. This review highlights several water treatment methods that can be used in removing heavy metal from water. Among various treatment methods, the adsorption process is considered as one of the highly effective treatments of heavy metals and the fu...

Water quality depends on its physicochemical and biological parameters. Changes in parameters such as pH, temperature, and essential and non-essential trace metals in water can render it unfit for human use. Moreover, the characteristics of the local environment, geological processes, geochemistry, and hydrological properties of water sources also affect water quality. Generally, groundwater is utilized for drinking purposes all over the globe. The surface is also utilized for human use and industrial purposes. There are several natural and anthropogenic activities responsible for the heavy me...

The positive interdependencies between marine-related ions and the release of most heavy metals in the riverine and estuarine environments indicate an increase in the mobility of heavy metals as a result of cation exchange reactions.

Adsorption is a widely used technology for removing and separating heavy metal from water, attributed to its eco-friendly, cost-effective, and high efficiency. Adsorption isotherm modeling has been used for many years to predict the adsorption equilibrium mechanism, adsorption capacity, and the inherent characteristics of the adsorption process, all of which are substantial in evaluating the performance of adsorbents. This review summarizes the development history, fundamental characteristics, and mathematical derivations of various isotherm models, along with their applicable conditions and a...

In this review, the synthesis strategy and postsynthesis modification preparation methods are summarized for water-stable MOFs (WMOFs), and the recent advances on the adsorption and photocatalytic reduction of heavy metal ions in water by WMOFs are reviewed.

Due to the serious threat of heavy metal oxoanions to human health and the natural environment, their efficient removal from water contaminants has become a vital issue. Currently, adsorptive removal is one of most promising approaches to purify contaminated water. Thus, the exploration of advanced adsorption materials has attracted widespread attention. Metal-organic frameworks (MOFs) with the advantages of tunable porosity, high surface area, and abundant functional groups are superior than conventional adsorbents. Herein, this review summarizes recent progress in different MOFs as outstandi...

With large specific surface area, abundant adsorption sites, flexible pore structure, and good water stability, Materials of Institute Lavoisier frameworks (MILs) have attracted increasing attention as effective environmental adsorbents. This review systematically analyzes and recapitulates recent progress in the synthesis and application of MIL-based adsorbents for the removal of aqueous heavy metal ions. Commonly used solvothermal, microwave, electrochemical, ultrasonic, and mechanochemical syntheses of MILs are first summarized and compared. Instead of focusing on adsorption process paramet...

Arsenic is a highly toxic metalloid that is extensively distributed in soils and water bodies, resulting in a variety of toxicity mechanisms and harmful effects on humans and environmental health. This paper comprehensively reviews the technological development in arsenic (As) removal from wastewater and contaminated soil, and provides insights into the challenges in effective arsenic removal from the environmental compartments. The arsenic removal efficiency of the available technologies is also discussed in terms of their principle of operation, efficiency, advantages, and shortcomings. Many...

The presence of heavy metals in the environment is an issue of great concern because of their growing discharge, toxicity, and other adverse effects on the receiving water. Adsorption has been proven to be one of the best options for pollution control in water in which functional organoclays are prominent candidates for treating wastewater containing heavy metal ions. This review deals with comprehensive information on the application of functional organoclays (polymer-, silane coupling agent-, surfactant-, ionic liquid- and other organics based organoclays) for heavy metal ions uptake from aq...

Heavy metals are toxic and non-biodegradable environmental contaminants that seriously threaten human health. The remediation of heavy metal-contaminated water and soil is an urgent issue from both environmental and biological points of view. Recently, nanomaterials with excellent adsorption capacities, great chemical reactivity, active atomicity, and environmentally friendly performance have attracted widespread interest as potential adsorbents for heavy metal removal. This review first introduces the application of nanomaterials for removing heavy metal ions from the environment. Then, the e...

Investigation of the synergistic influence of key water, sediment and ionic properties on the adsorption-desorption behavior of weakly-bound heavy metals provides fundamental knowledge for understanding the mobility and potential ecotoxicological impacts of heavy metals in aquatic ecosystems.

Heavy-metal (HM) pollution is considered a leading source of environmental contamination. Heavy-metal pollution in ground water poses a serious threat to human health and the aquatic ecosystem. Conventional treatment technologies to remove the pollutants from wastewater are usually costly, time-consuming, environmentally destructive, and mostly inefficient. Phytoremediation is a cost-effective green emerging technology with long-lasting applicability. The selection of plant species is the most significant aspect for successful phytoremediation. Aquatic plants hold steep efficiency for the remo...

The research progress in the adsorption of heavy metals in water treatment by electrospun nanofibrous membranes is reviewed and may provide an insight for the development of ENFMs-based adsorbents for heavy metals separation and water purification in the future.

Rapid industrialization, increased waste production and surge in agricultural activities, mining, contaminated irrigation water and industrial effluents contribute to the contamination of water resources due to heavy metal (HM) accumulation. Humans employ HM-contaminated resources to produce food, which eventually accumulates in the food chain. Decontamination of these valuable resources, as well as avoidance of additional contamination has long been needed to avoid detrimental health impacts. Phytoremediation is a realistic and promising strategy for heavy metal removal from polluted areas, b...

It is shown that sulfide-producing yeasts are able to remove mercury, lead and copper from real-world water samples and offer a platform for metal re-extraction through precipitation of metal sulfide nanoparticles.

The bioremediation mechanism of heavy metal ions in water by using microalgae and their modified products and the relevant research progresses since 2015 are critically reviewed and discussed.

Magnetic nanoparticles require a protective coating to enable them to be used to adsorb heavy metals from wastewater, given their oxidation properties and instability in acidic media. Humic acid (HA) has an affinity for magnetic nanoparticles, but its adsorption capacity is low. To improve adsorption capacity, we synthesized a novel adsorbent (HA-O/Fe3O4) through chemical modification and examined its adsorption of Pb (II), Cu (II), Cd (II), and Ni (II) ions. The effects of pH competition, adsorption mechanism, isotherm, kinetics, regeneration, and stability were investigated. The HA-O/Fe3O4 e...

The present work reports the adsorption behavior involved in the adsorption of heavy metal ions using a hybrid inulin-tetraethoxysilane (TEOS) adsorbent produced through the sol-gel process. An aqueous multi-element solution was used in order to examine the inulin-TEOS adsorbent efficiency in removing Cd2+, Co2+, and Ni2+ ions. The effects of the contact duration, adsorbent dosage, initial concentration, and solution pH on the adsorption of the targeted metal ions in batch systems were evaluated. The optimal conditions for the removal of all targeted heavy metals were as follows: 30 mg of an a...

The scarcity of clean water resources leads to many scientific and technological advancements in wastewater treatment processes. The recalcitrance of heavy metals in wastewater has been proven to be a challenging concern. Therefore, there is a need for more water treatment technologies to completely remove heavy metals down to a non-hazardous level. In this article, current development in recent waste-water treatment technologies to remove heavy metals has been reviewed and summarized. This review evaluates the state-of-the-art removal processes, including chemical precipitation, photocatalysi...

1. Atmospheric transport: large scale transport, models. European inventory of trace metal emissions to the atmosphere (J.M. Pacyna, J. Munch and F. Axenfeld). 2. Acid deposition and soil acidification The impact of atmospheric acid deposition on soil and vegetation (R. Mayer). Impact of soil acidification on the mobility of metals in the soil-plant system (E. Lobersli, E. Gjengedal and E. Steinnes). 3. Soil Interaction . Assessment of ecotoxicological risk of accumulated metals in soils with the help of chemical methods standardized through biological tests (S.K. Gupta). The effect of additio...

This study seeks to evaluate the quality of Kor River water located in southern Iran, and presents techniques for identifying the main sources of contaminations discharged to the river by neighboring factories. Water quality constituents, including water temperature, pH, total hardness, chloride, phosphate, nitrate, arsenic, cadmium, trivalent chromium, hexavalent chromium, copper, molybdenum, nickel, and zinc in twenty-nine stations along the river were evaluated during two years. The Dunnett statistical test and principal component analysis were employed to determine the most influential con...

The soil is uncontaminated to moderately contaminated with respect to all metals except the Cu and Pb and among the average daily dose of soil, ADDing and ADDinh for children had the maximum dose for all metals than adults while ADDderm was higher in adults.

Abstract Mitigation of toxic contaminants from wastewater is crucial to the safety and sustainability of the aquatic ecosystem and human health. There is a pressing need to find economical and efficient technologies for municipal, agricultural, aquacultural, and industrial wastewater treatment. Nitrogen-doped biochar, which is synthesized from waste biomass, is shown to exhibit good adsorptive performance towards harmful aqueous contaminants, including heavy metals and organic chemicals. Incorporating nitrogen into the biochar matrix changes the overall electronic structure of biochar, which f...

It can be concluded that functionalizing of cellulose-based aerogels with amine groups, thiol groups, other compounds such as nanobentonite and chitosan results in very high adsorption capacities.

The fabrication of a thiol-functionalized cellulose nanofiber membrane that can effectively adsorb heavy metal ions is reported, highlighting the significance of surface functionality on biocompatible, nontoxic, and sustainable cellulose materials to expand their potential and applicability towards water remediation applications.

The release of chemicals into water systems has resulted in pollution in many parts of the world, threatening human health and aquatic ecosystems. Sources of chemical discharge include industry, agricultural, wastewater treatment plants, and stormwater overflows. To combat water pollution, the European Union has introduced several directives that set concentration limits for chemicals in drinking water, surface water, and groundwater. To meet these limits, it is essential that rapid, reliable, and sensitive analytical detection systems be developed and put into use. This Review presents the pr...

The present review provides a comprehensive discussion on the above mentioned modification schemes of starch over the last 10-15 years highlighting their preparation methods, physico-chemical characteristics along with their adsorption capacities and mechanisms of heavy metal ions from water.

This study pioneers a schematic illustration of the underlying mechanisms of heavy metal bioremediation, pinpoints the research bottleneck during its real-world application as a low-cost and sustainable technology.

This comprehensive review elucidates the progress of using different concepts of membranes and potential novel materials for such separations, identifying that polymeric membranes can exhibit a removal efficiency from 77 up to 99%; while novel nanocomposite membranes are able to offer complete removal of heavy metals together with unprecedented permeation rates.

Heavy metals are highly toxic elements which are persistent in the natural environment, resulting in magnification throughout the food chain, adversely affecting both human and environmental health. Consequently, heavy metal pollution has received widespread research attention. This review assesses the current progress in heavy metal pollution monitoring, management and mitigations, which show a lack of systematic criteria for risk evaluation. Risk assessment and multivariate analysis methods are also discussed. Assessment of risk evaluation and multivariate statistical analysis are the basic ...

The obtained results reveal that waste water used for irrigation and farming of nearby areas and water drained from restaurant kitchens were considerably polluted and not suitable for aquatic organisms, irrigation, and agricultural purposes.

A new hybrid loose nanofiltration membrane with the positive surface charge was developed by self-assembly of Ethylenediamine (ED) grafted multi-walled carbon nanotube (ED-g-MWCNT) on the top layer of asymmetric Polyethersulfone (PES). The effects of different nanotubes loading on the membrane surface roughness, hydrophilicity, isoelectric point, and thermal and mechanical stabilities were evaluated. Due to the Donnan exclusion, the hybrid membranes exhibited excellent heavy metals rejection rates in the order of Zn (96.7%) > Mg (95.01%) > Cd (92.4%) > Cu (91.9%) > Ca (91.3%) > Ni (90.7%) > Pb...

Surface water and sediment samples from the most contaminated river in Taiwan, Houjing River, were collected for five years (2015 to 2019) and from five locations to study the contamination trends of eight heavy metals (As, Cd, Cr, Cu, Hg, Pb, Ni, and Zn). Five locations along the river were picked based on their potential of being contaminated by nearby industrial activities. The monitoring data, geo-accumulation index (Igeo), contamination factor (CF), modified degree of contamination (mCd), pollution load index (PLI), and metal index (MI) were used to provide a detailed assessment of the he...

This study examined the physicochemical parameters of water and sediments in the Naltar Lakes, northern Pakistan. Water and sediments were sampled and analyzed for physicochemical parameters. Heavy metals such as iron (Fe, 11% and 12%), nickel (Ni, 100% and 88%), chromium (Cr, 22% and 12%), and arsenic (As, 0% and 12%) of sampling sites had surpassed the threshold of drinking water set by world health organization (WHO) in the Naltar Lake I (Naltar I) and Naltar Lake II (Naltar II), respectively. Water quality parameters were evaluated for the drinking and irrigation water quality indices (WQI...

This study aims to treat heavy metal pollutants in water by applying red mud particle waste. An experiment on the static adsorption of heavy metal ions Pb2+ (or Cd2+ and Cu2+) by red mud particles was carried out, and the influences of the type of heavy metal ion, ion concentration, pH value, red mud dosage, reaction time, and temperature on adsorption performance were explored. The competitive adsorption mechanisms of various coexisting heavy metal ions by red mud particles were compared. The red mud samples loaded and not loaded with heavy metal ions were detected by zeta potential measureme...

The paper reviews the widely used heavy metal pollution indices (HPIs) in water, soil, and sediments and presents their numerical equation and application in various fields. HPIs are an essential and efficient tool to measure metal contamination in the environmental system. The present study includes twenty pollution indices from water, soil, and sediments for their comparative study with their ranges. In addition, the regional distribution of publications has been reviewed, and it observed that 68% were published from Asia, followed by other continents. The merits and demerits of each index h...

An LAC application strategy focused on LACs and optimized to work with other agronomic measures according to the classification of HM risk level for LACS is proposed, providing a cost-effective and practical solution for safe utilization of large areas of farmland polluted with low to moderate levels of HMs.

It is suggested that speciation and availability of HMs in hyperaccumulator are tunable by varying treatment techniques and reaction conditions, and this information should be useful for the selective conversion of hyper Accumulator into green and valuable products.