Highly efficient removal of endocrine disrupting pesticides by metal ferrites loaded Guar gum based green nanomaterials

Abstract

Numerous persistent and inexpensive pesticides are needed for industrial, domestic, and agricultural uses. Toxicity and bioaccumulation of pesticides have raised concerns for environment and demanding the efficient removal methods based on green nanomaterials. To substantiate this, the crystalline CdMgFe2O4@TiO2 nanocomposite incorporated in guar gum (GG) polymeric matrix (GG-CdMgFe2O4@TiO2) were employed to remove hazardous pesticides. Characterization showed that hybrid nanoparticles with polymer coating (particle size less than 100 nm) were successfully formed. PXRD revealed semi-crystalline nature and microscopic studies confirmed the wrapping of CdMgFe2O4@TiO2 with sheet like structure having size less than 100 nm. At optimum amount of GG-CdMgFe2O4@TiO2 (20 mg), Endosulfan (ES) (94%) and DDE (88%) degraded at neutral pH under sunlight. Both adsorption (GG-polymeric matrix) and photocatalytic degradation (CdMgFe2O4@TiO2) phenomenon followed for removal of target pesticides. Larger surface area (110 m2 g−1) and narrow band gap (1.9 eV) are evident for maximum eradication of pesticides by polymeric nanocomposites supports their excellent efficiency in terms of interactive and semiconducting feature. Removal phenomenon of pesticides followed Ist order kinetics and Langmuir adsorption was evident from the abrupt decrease in pesticides concentration followed by a steady reduction. Radical-scavenger analysis was used to investigate photo-catalytic reduction. LC-MS analysis proved that GG-CdMgFe2O4@TiO2 break down toxic pesticides into safer metabolites in presence of sunlight. In conclusion, polymeric GG-CdMgFe2O4@TiO2 nanocomposite may prove to be highly effective catalyst for industrial applications due to its high reusability (n = 9), higher charge separation, stability and high surface activity.