Chemical Extraction Process for Producing High Purity Nanosilica from Iraqi Rice Husk

Abstract

Rice husk is considered a main agricultural waste in Iraq. High purity SiO2 NPs were produced from rice husk by enhanced precipitation and developed leaching processes for the preparation of silica from RH. In this study, pre-treatment for rice husk was with 3N HCl, and calcination at 700°C was achieved, then followed with a leaching process with (1.5, 2, 2.5, 3) N NaOH concentrations. The characterizations of the prepared SiO2 NPs were studied by X-ray fluorescence (XRF), X-ray diffraction (XRD), and atomic force microscopy (AFM). The results show that the prepared SiO2 NPs have an amorphous structure with a high purity of 99.75%. The results of the X-Ray confirm the amorphous nature of the extracted SiO2 NPs. Also, the AFM results indicated that the average diameter of the SiO2 NPs was 85 nm. It was noted that the leaching processes and pretreatment methods determine the structure, particle size, and quality of the synthesized SiO2 NPs.

Characterization and Aerodynamics of Synthesized Polymeric Nanofibers via Electrospinning Process to Capture PM10 and PM2.5 from Air

“…obviously that some absorption peaks appeared at 1092 cm-1 assigned to the O-H stretching vibration of the hydroxy group, CH2 asymmetric stretching vibration, C=O carbonyl stretch. Also, effective peaks were presented at 1261.05 cm -1 according to ethers and aryl -O stretch, while, at 1736 cm -1 is attributed to carbonyl groups [8,19]. Actually, the prepared nanofibers (PAN and PVA) have a high surface area due to thin nanofibers in the network structure.…”

“…According to the results of Haider et al [1], Martins et al [3], and Cheng et al [20], the management and control of air velocity is the main factor in determining the performance through the air filter media. Then, each ventilation system keeping a constant level of air velocity for the HVAC ventilation system the range of air face velocity up to 4 m/s while for the industrial unit the velocity arrived at 8 m/s [19,25,40].…”

“…Usually, the used polymeric solutions have excellent thermal, structural, and chemical stability during the manufacturing process. The selection of nanofilter required managing of size, shape, and chemical structure of these filters to be suitable to capture the PMs [15][16][17][18][19][20]. Therefore, the nanofilters synthesis process using the electrospinning technique required a deep understanding of the type pollutants (PM10 and PM2.5) and their nature.…”