Water pollution is a worldwide issue that affects the human population around the world. Reliably, a lot of wastewater is created by industrial, horticultural and household activities and are stored in the land or water receptors (Reddy et al. 2022) (Chowdhary et al. 2020). The polluted water can cause harmful effects on aquatic as well as terrestrial life (Nagarajan &Venkatanarasimhan 2019) (Nagarajan &Venkatanarasimhan 2020). There is an increasing number of toxic pollutants in today's environment, requiring new materials to remove them. The occurrence of toxic dyes in water is one among them and they can slowly lead to serious health problems. Wastewater or effluents need to be treated in order to be reused or disposed without harming the environment or human health.
Organic dyes, Methylene blue (MB) and rhodamine B (RhB) are widely used in the textile industry and can cause various health issues when present in water (Karthik et al. 2018). Exposure to these dyes can lead to skin issues, eye problems, etc. (Tang et al. 2018). Various techniques such as coagulation, chemical oxidation, membrane filtration, adsorption etc. have been used for the removal of dyes from water (Crini &Lichtfouse 2019). In which adsorption obtained wide attention due to its low cost and higher efficiency (Bonilla-Petriciolet et al. 2017). Researchers prepared various adsorbent materials for the removal of such toxic dyes from water. Activated carbon (Xue et al. 2022) (Han et al. 2020), graphene oxide(Benjwal et al. 2015) (Huang et al. 2019), Fe3O4 (Zhang et al. 2013) are various adsorbent materials reported for the removal of MB. Sharma et al (Sharma et al. 2018) synthesized agrobacterium fabrum biomass along with iron oxide nanoparticles for the removal of MB and the material was showing a good regenerating capacity for four consecutive cycles. Similarly, various adsorbent materials such as polymer (KK &Gangadharan 2018), activated carbon (Zhang et al. 2021), silica (Joshiba et al. 2021), MOF (Liu et al. 2016), nanoparticles (Hund-Rinke &Simon 2006), nanocomposites(Skiba &Vorobyova 2020) etc. are used for the removal of contaminants (Elias et al. 2021) from water. Polymers and nanomaterials are among the newest emerging materials used to remove contaminants from water. Nanocomposites made of polymer materials have gained wide attention for their performance and ease of separation from contaminant solutions (Beyene &Ambaye 2019). Adding nanoparticles to polymers can improve their efficiency (Khodakarami &Bagheri 2021).
MnO2 is considered an efficient nanomaterial for wide range of applications. It is widely used in batteries (Liu et al. 2019), supercapacitors (Kubra et al. 2020), sensors (Cogal et al. 2021), and wastewater purification processes (KK &Gangadharan 2022). Different materials were modified with MnO2 nanoparticles to improve the adsorption efficiency (Cuong et al. 2021) (Verma et al. 2021). Dong et al (Dong et al. 2010) synthesized a MnO2 loaded resin for the simultaneous adsorption of lead and cadmium from the aqueous solution. Here, surface complexation plays a vital role in the adsorption of lead and cadmium on MnO2-loaded resin. Similarly, various materials have been prepared using MnO2 as a component. The separation of MnO2 nanoparticle from adsorbate solution is a challenge for researchers. To overcome this, copolymer beads can incorporate with MnO2 material for the easy separation of material from aqueous solution as well as to improve the adsorption capacity of material towards organic pollutants (Gangadharan et al. 2013). Column studies can also be performed by using copolymer beads. Nhat Ha et al (Nhat Ha et al. 2016) synthesized layered double hydroxide embedded polymer beads for the removal of arsenate ions via batch as well as column studies. The removal of contaminants via the column method is an advantage of using polymer beads-modified materials.
Herein, this research work focused on the synthesis, characterization and application of a copolymer-MnO2 nanocomposite. The as synthesized copolymer-MnO2 nanocomposite material was then analysed using powder XRD, SEM and optical microscope. The material is then equilibrated with organic pollutants to find the maximum adsorption capacity towards organic pollutant removal. As model pollutants, methylene blue and rhodamine B were used. Furthermore, the effect of contact time and concentration of pollutants on the material were studied. The regenerating capacity of the material was established by performing adsorption-desorption studies. The concentration studies were conducted by using a UV-Visible spectrophotometer.