What is the pore size range for ultrafiltration and what can it effectively remove?

Ultrafiltration is a membrane filtration process that operates with a pore size range of approximately 1 nanometer (nm) to 100 nanometers (nm). This process is particularly effective in removing a wide variety of contaminants from water. The correct answer indicates that ultrafiltration can effectively remove pathogens such as Giardia and Cryptosporidium, as well as larger bacteria, colloids, and viruses.

The specific range of 100 nm to 1 nm includes the sizes of many viruses and other pathogenic microorganisms, making ultrafiltration suitable for treating water that requires the removal of these contaminants. Additionally, the ability of ultrafiltration to retain larger particles in this range contributes to its effectiveness in producing clean water through the elimination of various diseases associated with waterborne pathogens.

In contrast, the other choices are incorrect because they either misrepresent the size range of ultrafiltration, the type of contaminants it can remove, or both. For example, stating that ultrafiltration only removes viruses overlooks its capability to eliminate a broader spectrum of pathogens, including larger microorganisms and organic materials.