BEIJING, Jan 14 (Reuters) - China’s exports grew more than expected in December as global demand for Chinese goods remained solid, while import growth quickened, customs data showed on Thursday. Exports rose 18.1% in December from a year earlier. Analysts in a Reuters poll had expected exports to grow 15% after a 21.1% jump in November. Imports, meanwhile, grew 6.5% last month from a year earlier, against expectations for a 5% rise and a 4.5% gain in November. China posted a trade surplus of $78.17 billion in December. Analysts in the poll had expected the trade surplus to narrow to $72.35 billion from $75.40 billion in November. (Reporting by Stella Qiu, Lusha Zhang and Gabriel Crossley; Editing by Ana Nicolaci da Costa)