May 12 (Reuters) - German speciality chemicals maker Lanxess raised the floor of its 2021 profit guidance range on Wednesday, driven by a further increase in demand, especially from the auto industry. The Cologne-based group now expects 2021 adjusted earnings before interest, tax, depreciation and amortisation (EBITDA) of 950 million to 1 billion euros ($1.15-1.21 billion), hiking the lower end from its previous forecast by 50 million.