Filter module having post-treatment filtration function

A filter module, comprising:

• a center tube having at least one purified water inlet on an outer peripheral surface thereof and provided at one end thereof with a connection portion having a purified water outlet defined therein;
• a reverse osmosis filter wound on the center tube, the reverse osmosis filter filtering raw water introduced through one end thereof and discharging the filtered raw water to the at least one purified water inlet;
• and
• a post-treatment filter disposed inside the center tube and allowing purified water introduced into the center tube to be post-treated by passing through the post-treatment filter,
• wherein the center tube comprises:
• a first tube member having the connection portion at one end thereof and having a first post-treatment filter mounting slot defined therein;
• and
• a second tube member detachably connected to another end of the first tube member and having a second post-treatment filter mounting slot defined therein to communicate with the first post-treatment filter mounting slot,
• wherein at least a portion of the post-treatment filter is disposed in the first post-treatment filter mounting slot, and another portion of the post-treatment filter is disposed in the second post-treatment filter mounting slot,
• wherein the first tube member is disposed therein with a purified water discharge partition having at least one purified water discharge hole defined therethrough,
• the second tube member is disposed therein with a separation partition dividing the second tube member into a front space and a rear space, and
• the post-treatment filter has a front end facing the purified water discharge partition and a rear end facing the separation partition.