Schmidt resigned his position at Yancoal effective on Sunday to pursue other career opportunities.
"Mr Schmidt made a significant contribution to Yancoal's growth and expansion, and he implemented many initiatives that have led to the company's strong operational and financial position," Yancoal said in a statement.
"His contribution to the company transforming Coal and Allied acquisition was invaluable, creating Australia's largest pure play coal producer."
Yancoal said Moult, 63, was an experienced CEO and company director with a career that spanned more than 40 years across the global mining and coal industries.
Moult was appointed as an independent non-executive director of Yancoal in 2018.
"During his tenure as a Yancoal director, he has been the chairman of the Health, Safety, Environment and Community Committee, a member of the Nomination and Remuneration Committee and a member of the Audit and Risk Management Committee," Yancoal said.
"The board considers that his broad experience, as well as existing knowledge of Yancoal's operations as an independent non-executive director, will provide continuity to the CEO role and enable Mr Moult to effectively implement the company's strategic priorities."
Moult was managing director and CEO of Centennial from 2011 to 2017, and then a non-executive director of Centennial from May 2017 until January 2018.
Before being appointed as CEO at Centennial, he had held the position of chief operating officer from 1998 to 2011.
Moult previously held senior management positions at Joy Mining Machinery in the US and Australia, RJB Mining PLC and British Coal in the UK.
He is a former director of the Minerals Council of Australia, former chairman and director of the New South Wales Minerals Council, former chairman and director of the Australian Coal Association Low Emissions Technology and a former director of the Newcastle Coal Infrastructure Group and the Port Kembla Coal Terminal.