* Merz becomes interim CEO for one year
* Russwurm to take over as chairman
* Group should keep majority in elevator unit - Giesler
* Workers will oppose any demand for special dividend (Adds comments from labour boss, top shareholder)
By Christoph Steitz and Tom Käckenhoff
FRANKFURT/DUESSELDORF, Germany, Sept 30 (Reuters) - Martina Merz, chair of Thyssenkrupp's supervisory board, will take over as chief executive on Oct. 1, the group said on Monday, hoping to end years of underperformance at the company and restore investor confidence.
Merz's appointment, agreed on unanimously by the group's supervisory board, will be for a maximum of 12 months, the group said, adding the contract with current CEO Guido Kerkhoff was terminated by mutual agreement.
The replacement confirms last week's announcement of a wider management reshuffle at the group, which has had a string of profit warnings and two botched restructurings.
"We are now looking to the future and continuing our strategic realignment. In the new executive board team we will take the structural decisions now on the agenda with the necessary consistency," Merz said.
Her biggest task will be to deliver on plans to sell or list Thyssenkrupp Elevator Technology (ET), the company's most profitable and healthiest asset, to bring in funds needed to restructure other divisions and pay down debt.
Tentative bids for ET, which analysts have valued at up to 17 billion euros ($18.5 billion), are expected in a month's time, sources told Reuters last week. Thyssenkrupp is also considering a partial listing of the division.
Knut Giesler, vice chairman of ET's supervisory board and head of the IG Metall union in North Rhine-Westphalia state, where Thyssenkrupp is based, said Thyssenkrupp needs to keep a majority holding in the business.
He said any proceeds from a sale would have to stay within the group and opposed the idea of a special dividend for shareholders: "The company needs to be stabilised. Whoever wants a special dividend must expect resistance."
Thyssenkrupp has paid a stable dividend of 0.15 euros per share for the past four financial years, but with shares down 38.8% over the past year and four profit warnings since July 2018, it is unclear whether this will be repeated.
Thyssenkrupp's biggest shareholder, the Alfried Krupp von Bohlen und Halbach foundation, welcomed Merz's appointment, saying the "urgently needed realignment decided in spring can now be swiftly pursued and implemented".
Thyssenkrupp's supervisory board also approved the appointment of Klaus Keysberg to the management board from Oct. 1. He will also remain head of the Materials Services business until a successor has been found.
"The new executive board team will strengthen the confidence of the capital markets, shareholders, customers and employees in our company. I am absolutely convinced of this," said Siegfried Russwurm, who will take over as chairman while Merz is CEO. ($1 = 0.9169 euros) (Editing by Thomas Seythal/Emelia Sithole-Matarise/Jane Merriman)