scispace - formally typeset
Search or ask a question

What are heavy metal adsorbents? 


Best insight from top research papers

Heavy metal adsorbents are materials or substances that have the ability to attract and bind heavy metals from water or wastewater. These adsorbents are used to remove heavy metals, such as mercury, lead, copper, and arsenic, which can be harmful to the environment and human health. Various types of heavy metal adsorbents have been developed and studied over the years. Some examples include methyl-esterified sericite , sulfide compounds combined with a carrier and surfactant , a combination of zeolite, crushed bark, humic acid, and other components , and manganese oxide produced by microorganisms . These adsorbents have been found to have high adsorption efficiency and can be used for the treatment of heavy metals in wastewater. They offer innovative and eco-friendly solutions for heavy metal remediation.

Answers from top 3 papers

More filters
Papers (3)Insight
Heavy metal adsorbents are substances used to remove heavy metals, such as mercury, from effluent gas. They consist of sulfide particles, carbon compounds, and a surfactant.
Heavy metal adsorbents are substances that can bind and remove heavy metals from wastewater or other solutions.
Book ChapterDOI
Reena Malik, Bhaskaran, Meena, Suman Lata 
01 Jan 2021
2 Citations
Heavy metal adsorbents are materials used to remove heavy metals from wastewater through the process of adsorption.

Related Questions

Cu adsorption of heavy metals in soil?4 answersCu adsorption of heavy metals in soil is an important process for understanding the fate of heavy metals and assessing environmental risks. Several studies have investigated the adsorption behavior of Cu in different soils. Boscov et al. found that a semiarid Brazilian bentonitic soil had a high potential for Cu adsorption, with a maximum adsorption capacity similar to other Brazilian soils. Gharbia et al. studied Cu adsorption in quartz sand and found that the adsorption capacity reached its peak value at an initial concentration of about 10 mg/L. Yang et al. developed machine learning models to predict Cu adsorption on soils and found that the gradient boosting decision tree had the best performance. Huang et al. investigated the influence of LDHs and microplastics on Cu adsorption in soil and found that the presence of LDHs increased the adsorption capacity. He et al. evaluated the ability of CaCO3 and clay to accumulate Cu in soil and found that increasing CaCO3 content enhanced Cu adsorption.
Which type of organic adsorbents are most effective for the removal of metal ions from agricultural effluents?5 answersOrganic adsorbents such as chitosan, carboxymethyl cellulose, alginate, and lignin-based nanocomposites have shown to be effective for the removal of metal ions from agricultural effluents. These adsorbents have been extensively used due to their biodegradability, non-toxicity, and low cost. They have been synthesized and modified to enhance their adsorption capacity and selectivity for heavy metals such as Cd2+, Pb2+, and Zn2+. Functionalization with nanomaterials has further improved their performance and recyclability. Additionally, mercaptocarboxylic acid/layered double hydroxide (MPA/LDH) adsorbents have demonstrated excellent adsorption capacities for heavy metal ions such as Hg2+, Pb2+, and Cu2+. The inner-sphere surface complexation between the heavy metal ions and the functional groups in MPA/LDH contributes to their high adsorption performance. Furthermore, hydrogel-based adsorbents, such as the porous hydrogel T-PMADA, have shown promise for the simultaneous removal of heavy metal ions and organic dyes from agricultural effluents. These adsorbents provide a new strategy for water pollution treatment in complex polluted environments.
Is silica gel used as a commercial adsorbent for heavy metal adsorption?5 answersSilica gel is used as a commercial adsorbent for heavy metal adsorption. It has been modified with different materials to enhance its adsorption capacity. For example, Sulejmanović et al. developed SiO2–Ta2O5 as a new sorbent for simultaneous preconcentration of various metal ions from water. Vareda and Durães studied tailored adsorbents for heavy metal uptake, including silica gel, in batch tests for decontaminating polluted environments. Zongchen developed a porous spherical silica gel loaded with nanometer TiO2 for wastewater heavy metal adsorption, including Cd, Cr, Cu, and As. Nuengmatcha et al. modified commercial silica gel with 3-aminopropyl-trimethoxysilane to acquire amino groups for the removal of iron from aqueous solution. Guo et al. prepared a magnetic silica gel adsorbent (Fe3O4-Si-COOH) for the adsorption of Pb, Zn, and Cd from wastewater. Therefore, silica gel is widely used as a commercial adsorbent for heavy metal adsorption, and its properties can be enhanced through modification with different materials.
How heavy metal ion concentrations affect heavy metal ion adsorption?3 answersHeavy metal ion concentrations have a significant impact on heavy metal ion adsorption. The adsorptive capacities of heavy metals are controlled by different mechanisms depending on the concentration of ions present. As the ionic strength increases, the adsorption of heavy metals increases due to the compression of the electric double layer. However, it decreases due to the decreasing ionic activities of the heavy metals. Competitive adsorption and complexation between heavy metals and common ions also play a role in controlling heavy metal adsorption. The concentrations of common ions such as Na+, Mg2+, K+, and Ca2+ can affect the adsorption of heavy metals, with an increase in these ions leading to increased adsorption of certain heavy metals like Zn2+. The temperature of the adsorption medium is another important parameter, with thermodynamic analysis indicating that the adsorption of heavy metals by green adsorbents is spontaneous in most cases.
What ar the Advantages and disadvantages of different types of heavy metal adsorbents?3 answersAdsorption is a cost-effective technique for heavy metal removal from wastewater. The advantages of different types of heavy metal adsorbents include cost-effectiveness, technical applicability, easy availability of raw materials, and minimum waste disposal. Low-cost adsorbents derived from natural materials, industrial byproducts, agricultural wastes, and biopolymers have been developed and applied for heavy metal removal. Nano-adsorbents, such as chitosan-based adsorbents, have a large surface area, high adsorption rates, and short adsorption equilibrium durations, making them effective for heavy metal removal. Lime precipitation, new adsorbents, and membrane filtration are also effective techniques for heavy metal-contaminated wastewater treatment. However, there are some limitations to consider. Activated carbon, the most widely used adsorbent, has a high cost of production and regeneration. The selection of the most effective treatment system for contaminated wastewater should consider factors such as pH, initial metal concentration, overall treatment results, environmental impact, and economics.
What are the mechanism of heavy metal adsorbents?2 answersHeavy metal adsorbents have different mechanisms for adsorption. The adsorption capacity of cellulose-modified adsorbents is due to the loading of functional groups such as amino groups, sulfydryl groups, and carboxyl groups. Various adsorbents, including natural materials, synthetic materials, agricultural materials, biopolymers, and commercial materials, have been used for the extraction of metal ions. The adsorption isotherm explains the relation between the amount adsorbed and the concentration, while the adsorption kinetics data provide insights into the reaction pathways and mechanism of the sorption reaction. Clay minerals and modified clays, such as halloysite, bentonite, montmorillonite, vermiculite, and attapulgite, have been found to be efficient adsorbents for heavy metal removal. The main adsorption mechanisms include ion exchange, surface complexation, and precipitation. Modified biochar adsorbents (MBAs) have also been developed for heavy metal adsorption, with various modification methods such as organic-modified, nonmetal-modified, metal-modified, metal/organic-modified, and metal/mineral-modified. The adsorption mechanism of MBAs is diverse and competitive adsorption is inevitable in mixed multi-metal solution systems.