Preparation of alkali lignin extracted from ligno-cellulosic populus tremula fibers: Application to copper oxide nanoparticles synthesis, characterization, and methylene blue biosorption study

The green synthesis of nanoparticles using biogenic approaches constitutes a challenge for effective applications. The massive aliphatic hydroxyl groups of lignin exhibited excellent reduction properties allowing the production of metallic nanoparticles. In this work, alkali lignin was extracted from virgin populus tremula and used for the preparation of copper oxide nanoparticles. The analysis of the prepared nanoparticles was assessed using Fourier Transform Infra-red (FT-IR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX), and Transmission Electron Microscopy (TEM). FT-IR results displayed that different phytochemicals constituents of lignin extract were responsible for the production of CuO nanoparticles. XRD information demonstrated monoclinic CuO nanoparticles with a mean size of 12.4 nm. SEM images showed that some nanoparticles were quite separated from each other and some of them were agglomerated due to the oxidation of metal nanoparticles. TEM photos indicated that the overlap of the nanoparticles resulted in rect-angular patterns due to the presence of lignin on the surface of CuO nanoparticles. Finally, the prepared CuO nanoparticles were applied for the removal of methylene blue from water. The results showed that the maximum adsorption capacity reached 85 mg/g at the following conditions: T = 20 degrees C, pH = 6, and time = 60 min.

Automated summary

Green synthesis of copper oxide (CuO) nanoparticles was achieved by extracting alkali lignin from virgin populus tremula. The nanoparticles were characterized using FT-IR, XRD, SEM, EDX, and TEM, revealing the influence of different phytochemical constituents of lignin extract on the production of CuO nanoparticles. The prepared CuO nanoparticles exhibited a mean size of 12.4 nm and rectangular patterns due to the presence of lignin on the surface. Furthermore, these nanoparticles showed excellent adsorption capacity for methylene blue removal from water under specific conditions (T = 20 °C, pH = 6, and time = 60 min).