Is there any chance to travel without visa? Urgent business trip from Spain to Xi'an.

I am afraid that it's difficult to do that. Although the related rule says that foreigners who com to PRC for humanitarian reasons, or are invited to enter for urgent business or rush repair work, or have other urgent needs can come to PRC and apply for the VOA at the designated ports. Howeve, they are required to provide materials that prove the competent departments' approval of their applications at the port.

I am not sure if your boss can get the approval.