Agent for Increasing Rejection with a Permeable Membrane, Process for Increasing the Rejection, Permeable Membrane and Process for Water Treatment

摘要

An agent for increasing the rejection with a permeable membrane which comprises an ionic macromolecule having a weight-average molecular weight of 100,000 or greater; a process for increasing the rejection with a permeable membrane which comprises treating a permeable membrane with the agent; a permeable membrane which is treated in accordance with the process; and a process for water treatment which comprises using the permeable membrane are disclosed. By using the above agent, an increased rejection of inorganic electrolytes and organic compounds soluble in water can be maintained for a long time easily and safely at the location of the use of the membrane without extreme decrease in the flux of permeation in the membrane separation using a selective permeable membrane such as a nano filtration membrane and a reverse osmosis membrane.