Source: Sharecast
Schoolenberg, who has served as non-executive senior independent director since April 2022, will succeed John O'Higgins, who previously announced that he would not stand for re-election.
Elementis said that Schoolenberg, who also serves as chair of Accsys Technologies, was "well placed" to lead the firm as it enters its "next phase of growth".
The FTSE 100-listed firm added that Christine Soden, non-executive director, will be appointed as interim senior independent director.
Chief executive Luc van Ravenstein said: "I would like to congratulate Trudy on her appointment as chair. Her broad international experience, deep knowledge of the industry and respected position within Elementis make her the right leader at this important juncture for the business."
As of 0945 GMT, Elementis shares were down 1.83% at 150p.
Reporting by Iain Gilbert at Sharecast.com
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