Since the beginning of the third Millennium, specifically during the last 18 years, three outbreaks of diseases have been recorded caused by coronaviruses (CoVs). The latest outbreak of these diseases was Coronavirus Disease 2019 (COVID-19), which has been declared by the World Health Organization (WHO) as a pandemic. For this reason, current efforts of the environmental, epidemiology scientists, engineers, and water sector professionals are ongoing to detect CoV in environmental components, especially water, and assess the relative risk of exposure to these systems and any measures needed to protect the public health, workers, and public, in general. This review presents a brief overview of CoV in water, wastewater, and surface water based on a literature search providing different solutions to keep water protected from CoV. Membrane techniques are very attractive solutions for virus elimination in water. In addition, another essential solution is nanotechnology and its applications in the detection and protection of human and water systems.

The major scope of this study is the fabrication and development of a substrate and polyamide rejection layer for an efficient thin-film hydrophilic composite forward osmosis (TFC-FO) membrane. Fabrication of a thin-film nanocomposite forward osmosis membrane employing interfacial polymerization and modification of substrate characteristics using titanium dioxide (TiO2) nanoparticles as additives (TFNC-FO) are studied. Characterizations of the prepared TFC-FO and TFNC-FO membranes were determined. The morphologies of cross-section, upper and bottom surfaces for the TFC-FO and TFNC-FO membranes were studied using scanning electron microscopy (SEM). Energy-dispersive X-ray (EDX) spectroscopy was used to examine the compositions of different elements for both membranes. The hydrophilicity of the prepared TFC-FO and TFNC-FO membranes was investigated using the measurement of the contact angle test. A Fourier Transform Infrared (FT-IR) spectrophotometer was used to observe the existing functional groups of the TFC-FO and TFNC-FO membranes. The thermal stability of the membrane was evaluated via thermogravimetric analysis (TGA). The overall performance of TFC-FO membranes was evaluated with and without adding TiO2 nanoparticles through different parameters, such as membrane flux, initial feed concentration, draw solution concentrations, reverse solute fluxes, membrane permeabilities, and finally, the effect of FO membrane orientations. FO membrane performance was successfully enhanced by adding different concentrations of TiO2 nanoparticles from 0.5 to 1.5 wt%. The findings indicated that an increase in the concentration from 0.5 to 1 wt% leads to a clear increase in both the porosity and hydrophilicity of the nanocomposite substrate and consequently, an increase in the water flux. However, further increasing the concentration of TiO2 nanoparticles to more than 1 wt% affects the membrane performance.