What is the ruling on the one who reads the Quran and watches pornography on the same device? Is it Kufr (disbelief) because he is degrading the Quran? What is the ruling on sending Quranic verses on Facebook, on which you can find sexual content also?

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.

It is impermissible to watch pornography. Allah, the Almighty, commanded the believers to lower their gaze; He said (what means): {Tell the believing men to reduce (some) of their vision and guard their private parts. That is purer for them. Indeed, Allah is Acquainted with what they do. And tell the believing women to reduce (some) of their vision and guard their private parts...} [Quran 24:30-31]

The Shaafi‘i scholar Al-Bujayrimi wrote in his commentary on Sharh Al-Khateeb, “What is unlawful in itself, it is unlawful to watch it, because that constitutes approval of it, as stated by Ibn Qaasim in his comment on Al-Manhaj (a book written by Shaykh Zakariyya al-Ansaari).”

As for reciting the Quran using the same device that is used for watching pornography, this is not Kufr in and of itself as long as the person did not intend to mock the Quran and disrespect it by his action.

As for sending Quranic verses on Facebook, there is no harm in that, and this is not prevented by the fact that the device or software may be used for evil purposes, because the device and the internet are mere instruments; it is incumbent on the Muslim to use them for lawful purposes only. If he slipped and used them for an evil purpose, this is not a reason not to use them for a good purpose.

Allah knows best.