* Shareholders to get 1 share in each new co per Cookson share
* New listed specialty chemicals co to be called Alent
* Engineered ceramics division to be renamed Vesuvius Plc
* Cevian Capital to have 1 represtative on each board
* Shares rise as much as 4.7 pct (Adds comments from Cevian and analyst, details, background; Updates share movement)
Nov 1 British industrial materials supplier Cookson Group Plc said it will split into two companies, one focusing on specialty chemicals and the other on engineered ceramics.
The move was welcomed by Cevian Capital, which holds about a fifth of Cookson. Shares in the company rose as much as 4.7 percent in early trading on Thursday.
Cookson, valued at 1.62 billion pounds ($2.61 billion) said it believed both the new companies would rank as FTSE 250 companies.
The company's performance materials division - which supplies materials and chemicals to the electronics, automotive, industrial and construction markets - would form a London-listed company called Alent Plc.
Cookson's engineered ceramics division, whose products are used in the glass and solar industries as well as by steelmakers and foundries, would be renamed Vesuvius Plc.
"Of the two demerged entities Alent is set to carry less baggage," Panmure Gordon analyst Oliver Wynne-James wrote in a note.
Cookson's engineered ceramics unit, which fetches about half the company's revenue, has suffered from a downturn in steel production, particularly in Europe.
The company said last month that it would miss its profit forecasts for the year.
Activist investor Cevian Capital said founding partner Christer Gardell, who is a non-executive director with Cookson, will continue on the board of Vesuvius. Another founding partner, Lars Forberg, would join the board of Alent.
"(The appointments) underline our commitment to work to realize the companies' full value potential in the best interest of all shareholders," Harlan Zimmerman, senior partner of Cevian Capital, London, said.
Every Cookson shareholders would receive one share in each of the two new entities for every Cookson share they hold, the company said.
The company floated the idea of a demerger in May, after months of speculation about a break-up.
Shares in the company, which have fallen 14 percent since Cookson flagged the possibility of splitting itself, were up 2.6 pct at 597.5 pence at 0843 GMT on the London Stock Exchange. ($1 = 0.6207 British pounds) (Reporting by Brenton Cordeiro in Bangalore; Editing by Joyjeet Das)