Construction of individual portable multi-layer water purification filter for use in emergency situations

In this work, the design, construction, and performance evaluation of a light and portable compressed water purifier with antimicrobial properties have been studied. The main components of this filter include gravel and sand, silica nanoparticles, activated carbon and clinoptilolite zeolite coated with silver nanoparticles. These components are arranged in series in a cylindrical glass container to remove various pollutants from water. At first, the surface of silica nanoparticles was modified with 3-aminopropyltriethoxysilane, and the surface of activated carbon was functionalized with nitric acid, and in the next step, it was coated with silver nanoparticles. In addition, natural clinoptilolite zeolite was coated with silver nanoparticles using a chemical reduction method. The composites were evaluated using different analyses, including: scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDAX). Water samples before and after passing through the multi-layer filter were evaluated through pH test, turbidity test, total hardness test, counting the most probable number of bacteria (MPN), biological oxygen demand test (BOD) and chemical oxygen demand test (COD). The advantages of this filter are: First, it exhibits strong antibacterial performance and effectively reduces the load of microbial contamination in water. Secondly, it can reduce turbidity, BOD, and COD parameters in water, showing its efficiency in water purification. In addition, it showed a high performance in reducing the total hardness and the amount of chloride and nitrate. The filter does not need an external power source. The results show that the designed filter is a very efficient and desirable water purification device.