Superabsorbent Hydrogels for Heavy Metal Removal

Abstract

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.

Recent advances in biochar engineering for soil contaminated with complex chemical mixtures: Remediation strategies and future perspectives

“…A hydrogel is a three-dimensional network of hydrophilic polymers which are crossed-linked and flexible, and that can swell in water or biological fluid and retain a large volume of water while maintaining its structure (Chai et al, 2017;Ahmed, 2015). Apart from its widespread applications in bioengineering, biomedicine, agriculture, sensors, food industry and water purification and separation processes (Annabi et al, 2014;Zhou et al, 2017;Liu and Li 2017;Xu et al, 2017), hydrogels have been recently used as a sorbent for the removal of metal ions from water and aqueous media (Rehman et al, 2019;Pathan andBose, 2018, Du et al, 2020). The application of hydrogels in metal removal is attributed to its hydrophilic properties, largely conferred by hydrophilic functional groups, such as hydroxyl, carboxyl, sulfonic acid and amide (Rehman 2019;Askari et al, 1993).…”

Sorption of heavy metal ions by polyampholyte hydrogels

“…Перспективными сорбентами являются полиамфолитные гидрогели, которые содержат в своей структуре кислотные и основные функциональные группы. Они обладают устойчивостью к изменению рН, а также могут взаимодействовать с разноименно заряженными веществами [4].…”

Remoción de Cromo, Hierro y Manganeso de aguas contaminadas utilizando criogeles como adsorbente

“…Algunos iones de metales pesados, incluyendo el Cr 3+ , Fe 3+ y Mn 2+ son significativamente tóxicos para el ser humano si se introducen en la cadena alimentaria y se ingieren más allá de las concentraciones pre-establecida (Fu et al, 2019;Li, Wang, Wu, Chen, & Wu, 2013). En Nicaragua, la remoción de estos iones de metales pesados del agua contaminada es una tarea difícil para los investigadores, ya que la mayoría de las industrias carecen de la tecnología y las instalaciones para tratar las aguas residuales antes de ingresar a los cuerpos receptores (Ur Rehman et al, 2019). La adsorción es uno de los métodos útiles para reducir el contaminante de metales pesados en el medio ambiente (Lesbani, Turnip, Mohadi, & Hidayati, 2015), y es ampliamente adoptada debido a su operación simple, bajo costo y alta eficiencia (Fu et al, 2019).…”