Scholarlink

<p>Alginate-based composites are emerging as viable, environmentally friendly materials capable of removing detrimental heavy metals from water systems. This review evaluates recent progress in alginate-modified composites for the removal of heavy metals, such as Hg, Cd, As, Pb, Cr, Ni, Cu, Mn, Fe, and Zn, from aqueous media. Alginate-based composites are comprehensively evaluated for adsorption mechanism, application feasibility, and regeneration performance. Reported adsorption capacities ranged from 100 to 800&#xa0;mg&#xa0;g<sup>−1</sup> depending on the target metal species, material functionalization, and operating conditions. Optimum removal occurs when their pH is acidic to near-neutral, roughly between 2 and 6. Functionalization techniques like amine group grafting, incorporation of metal oxides, or nanomaterials result in a 2–sixfold increase in adsorption capacity, due to increased active-site density and stronger metal–ligand interactions. Crosslinking and surface grafting modifications introduce ionizable functional groups (–NH<sub>2</sub>, –COOH, –OH) that regulate surface charge and promote adsorption via electrostatic attraction, complexation, and ion-exchange mechanisms. The reported studies demonstrate pseudo-second-order kinetics and Langmuir isotherm behavior, indicating chemisorption-dominant processes with monolayer surface coverage. The thermodynamic parameters (ΔG°, ΔH°, ΔS°) show that the adsorption process is spontaneous and endothermic under optimized conditions. Column experiments reveal that the breakthrough point occurs ~ 150–300 BV, indicating stable dynamic adsorption performance and thus proving the feasibility of continuous-flow operation. Most alginate-based adsorbents are reusable across at least five cycles of adsorption and desorption, with 75–80% removal efficiency. Although laboratory breakthroughs have been made, large-scale production, mechanical stability, desorbate control, and post-treatment disposal remain major barriers to commercialization. This paper summarizes the performance trend and suggests scalable, circular, and environmentally friendly heavy-metal cleanup systems.</p> Graphical abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

A comprehensive review of alginate based composite adsorbents for heavy metal removal from wastewater

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年7月16日

查看全文
  • Prajakta Magdum,
  • Nilisha Itankar

摘要

Alginate-based composites are emerging as viable, environmentally friendly materials capable of removing detrimental heavy metals from water systems. This review evaluates recent progress in alginate-modified composites for the removal of heavy metals, such as Hg, Cd, As, Pb, Cr, Ni, Cu, Mn, Fe, and Zn, from aqueous media. Alginate-based composites are comprehensively evaluated for adsorption mechanism, application feasibility, and regeneration performance. Reported adsorption capacities ranged from 100 to 800 mg g−1 depending on the target metal species, material functionalization, and operating conditions. Optimum removal occurs when their pH is acidic to near-neutral, roughly between 2 and 6. Functionalization techniques like amine group grafting, incorporation of metal oxides, or nanomaterials result in a 2–sixfold increase in adsorption capacity, due to increased active-site density and stronger metal–ligand interactions. Crosslinking and surface grafting modifications introduce ionizable functional groups (–NH2, –COOH, –OH) that regulate surface charge and promote adsorption via electrostatic attraction, complexation, and ion-exchange mechanisms. The reported studies demonstrate pseudo-second-order kinetics and Langmuir isotherm behavior, indicating chemisorption-dominant processes with monolayer surface coverage. The thermodynamic parameters (ΔG°, ΔH°, ΔS°) show that the adsorption process is spontaneous and endothermic under optimized conditions. Column experiments reveal that the breakthrough point occurs ~ 150–300 BV, indicating stable dynamic adsorption performance and thus proving the feasibility of continuous-flow operation. Most alginate-based adsorbents are reusable across at least five cycles of adsorption and desorption, with 75–80% removal efficiency. Although laboratory breakthroughs have been made, large-scale production, mechanical stability, desorbate control, and post-treatment disposal remain major barriers to commercialization. This paper summarizes the performance trend and suggests scalable, circular, and environmentally friendly heavy-metal cleanup systems.

Graphical abstract