The explanation comes in an article recently published in the Boston Globe:
Turkey’s odd position on Libya is rooted in its large investments in the country and close personal contacts of Prime Minister Erdogan with Moammar Khadafy. In addition to the well-publicized "human rights" award that Erdogan received from Khadafy, there are more pressing national economic interests at play. Over the past ten years Turks have won almost all lucrative construction contracts in Libya. Consequently, as many as 30,000 Turkish citizens were working and doing business in Libya at the time of the uprisings.