Hexamethyldisilazane Removal with Mesoporous Materials Prepared from Calcium Fluoride Sludge

Area of Science:

• Materials Science
• Environmental Engineering
• Chemical Engineering

Background:

• The semiconductor industry generates significant calcium fluoride sludge, posing a disposal challenge.
• Current volatile organic compound (VOC) treatment methods are fuel-intensive.
• Hexamethyldisiloxane (HMDS) is used in semiconductor manufacturing, leading to silicon dioxide formation that can block porous materials.

Purpose of the Study:

• To develop a sustainable adsorbent from calcium fluoride sludge for VOC treatment.
• To investigate the adsorption performance of mesoporous silica materials synthesized from calcium fluoride (CF-MCM) for HMDS removal.
• To characterize the synthesized CF-MCM materials and evaluate operational parameters.

Main Methods:

• Synthesis of mesoporous silica materials from calcium fluoride sludge (CF-MCM).
• Characterization using X-ray Diffraction (XRD), X-ray Fluorescence (XRF), Fourier-Transform Infrared Spectroscopy (FTIR), and N2 adsorption-desorption.
• Testing HMDS adsorption capacity at different concentrations (100 and 500 ppm).
• Analysis of operational parameters like contact time and mixture concentration.

Main Results:

• CF-MCM materials exhibited high specific surface area, large pore volume, and large pore diameter.
• TEM images showed crystal patterns similar to Mobil composite matter (MCM-41).
• Adsorption capacities for HMDS reached 40 mg g-1 at 100 ppm and 80 mg g-1 at 500 ppm.

Conclusions:

• Mesoporous silica materials synthesized from calcium fluoride sludge are effective adsorbents for HMDS.
• CF-MCM offers a promising, sustainable alternative for VOC treatment in the semiconductor industry.
• Further studies should optimize operational parameters for enhanced performance.