College of Science and Engineering, James Cook University, Townsville, QLD, 4811, Australia.
College of Science and Engineering, James Cook University, Townsville, QLD, 4811, Australia.
J Environ Manage. 2021 Mar 1;281:111918. doi: 10.1016/j.jenvman.2020.111918. Epub 2021 Jan 8.
Silver nanoparticles are one of the most beneficial forms of heavy metals in nanotechnology applications. Due to its exceptional antimicrobial properties, low electrical and thermal resistance, and surface plasmon resonance, silver nanoparticles are used in a wide variety of products, including consumer goods, healthcare, catalysts, electronics, and analytical equipment. As the production and applications of silver nanoparticles containing products increase daily, the environmental pollution due to silver nanoparticles release is increasing and affecting especially the aqueous ecosystem. Silver nanoparticles can kill useful bacteria in soil and water, and bioaccumulate in living organisms even at low concentrations from 10 to 10 μg/mL silver can show antibacterial effect. On the other hand, the maximum silver discharge limit into freshwater is 0.1 μg/L and 3.2 μg/L for Australia and the USA, respectively. To reduce its toxic consequences and meet the regulatory guidelines, it is crucial to remove silver nanoparticles from wastewater before it is discharged into other water streams. Several technologies are available to remove silver nanoparticles, but the adsorption process using low-cost adsorbents is a promising alternative to mitigate silver nanoparticle pollution in the bulk stage. As one of the low-cost adsorbents, biochar produced from the biomass waste could be a suitable adsorbent. This review focuses on collating the latest evidence on silver nanoparticle production, applications, environmental consequences, and cost-effective technological approaches for silver removal from wastewater.
纳米银颗粒是纳米技术应用中最有益的重金属形式之一。由于其具有出色的抗菌性能、低电阻和热阻以及表面等离子体共振，纳米银颗粒被广泛应用于各种产品，包括消费品、医疗保健、催化剂、电子产品和分析设备。随着含银纳米颗粒产品的生产和应用日益增加，由于银纳米颗粒释放而导致的环境污染也在增加，并特别影响到水生态系统。纳米银颗粒会杀死土壤和水中的有益细菌，并在低浓度下（从 10 到 10μg/mL 即可）在生物体中生物累积，表现出抗菌效果。另一方面，澳大利亚和美国分别将淡水的最大银排放限值设定为 0.1μg/L 和 3.2μg/L。为了降低其毒性后果并符合监管指南，在将废水排放到其他水流之前，必须从废水中去除纳米银颗粒。有几种技术可用于去除纳米银颗粒，但使用低成本吸附剂的吸附过程是减轻批量阶段银纳米颗粒污染的一种很有前途的替代方法。作为低成本吸附剂之一，由生物质废物制成的生物炭可能是一种合适的吸附剂。本综述重点总结了有关银纳米颗粒生产、应用、环境后果以及从废水中去除银的经济高效技术方法的最新证据。
