Clean water generation through a multifunctional activated carbon-TiO₂ interfacial solar distillation system

Area of Science:

• Materials Science
• Environmental Engineering
• Chemical Engineering

Background:

• Solar distillation offers a sustainable approach to clean water generation.
• Challenges include bulk water heating and complex source water compositions affecting system efficiency.
• Interfacial evaporation presents a promising alternative to conventional methods.

Purpose of the Study:

• To develop and evaluate an interfacial evaporation device for enhanced solar water distillation.
• To improve evaporation rates and water purification efficiency compared to existing systems.
• To assess the device's performance in desalination and removal of volatile organic compounds.

Main Methods:

• Fabrication of an interfacial evaporation device using activated carbon, P25 TiO2, and polyethylene foam (AC-P25/foam).
• Testing the device's evaporation rate under solar irradiation.
• Evaluating reusability, performance with suspended solids, and removal of phenol.
• Conducting outdoor solar distillation tests with synthetic saline water.

Main Results:

• The AC-P25/foam device achieved an evaporation rate of 2.1 kg m⁻² h⁻¹, significantly higher than water-only and submerged systems.
• Stable performance was observed over 7 cycles, with reduced impact from suspended solids.
• Approximately 95% removal efficiency for phenol was achieved through adsorption and photocatalysis.
• Distilled water from saline water had ion concentrations ≤3.5 mg L⁻¹, meeting WHO drinking water standards.

Conclusions:

• The AC-P25/foam interfacial evaporation device demonstrates high efficiency and effectiveness for solar water distillation and desalination.
• The device's design overcomes limitations of bulk heating and is robust against water impurities.
• Readily available materials and ease of fabrication highlight the practical feasibility for clean water generation.