Organic-inorganic hybrid modified silica synthesized from rice husks straw for effective uptake of Co(II), Ni(II), and Cu(II) ions from aqueous solutions

The world is moving toward using the best scientific methods to get rid of environmental pollution. Rice husks are one of the agricultural wastes produced daily in all parts of the world. Therefore, it was found in the previous literature to use this substance in producing valuable materials because of its high percentage of silica. Sodium silicate was prepared from rice husks, then reacted with 3-(aminopropyl)triethoxysilane to produce RH-SiO2PrNH2, and then reacted with 2-amino-3,5-dibromobenzaldehyde to produce RH-SiO2PrADB. CHN and FTIR techniques were relied upon to propose the synthesis of the prepared compound. X-ray procedure revealed the amorphous nature of the compound. N2 adsorption-desorption analysis showed a specific surface area of 0.789 m2 g-1 for RH-SiO2PrNH2 and 3.818 m2 g-1 for RH-SiO2PrADB. The modified organic-inorganic silica displayed a restricted 3-20-nm pore size distribution. The particles and pores of organic-inorganic hybrid modified silica were found to be randomly dispersed, with a tendency to be uniformly spherical particles, according to atomic force microscopy (AFM) analysis, field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The uptake results showed that the maximum adsorption efficiency in acidic medium was up to 96%, 95.5%, and 95% for Co(II), Ni(II), and Cu(II), respectively. Under the impact of various circumstances, the produced RH-SiO2PrADB was employed to extract the metal ions Co(II), Ni(II), and Cu(II) from their aqueous solutions.