** Shares of Calix CXL.AX rise 9.1% to A$0.54, their highest level since Feb. 6

** Environmental technology co says it has restarted its mid-stream demonstration plant project developed in a joint venture with Pilbara Minerals PLS.AX

** Recommencement follows execution of an A$15 million ($9.42 million) grant from the Government of Western Australia - co

** Stock rose as much as 12.1% earlier in the day, marking its biggest intraday gain since Sept. 10, 2024

** CXL down 28% YTD

($1 = 1.5918 Australian dollars)

(Reporting by Adwitiya Srivastava in Bengaluru)

((Adwitiya.Srivastava@thomsonreuters.com))