Oil could hit $100 per barrel within the next 18 months, Egyptian billionaire Naguib Sawiris told CNBC on Wednesday—a hard pill to swallow with Brent currently trading below $30 per barrel. Sawiris, chairman of one of Egypt’s largest companies, Orascom Telecom Media and Technology Holding S.A.E., is Egypt’s second-richest man and has a net worth somewhere between $3 billion and $7.5 billion. It’s hard to pin down because net worth is a (downward) moving target these days. Sawiris told CNBC that he would buy airline…