Is it permissible to publish a daily Quranic portion consisting of 5 pages in groups via social media to remind people and encourage them to read the Quran?

There is no harm in publishing a specific portion of the Quran daily on social media to encourage people to read it, because it reminds them to recite their daily portion of the Quran. This falls under cooperating in righteousness and piety, and enjoining one another to truth.