** British chemicals firm Johnson Matthey's JMAT.L shares soar to a one-year high, last up ~30% to 1,792p ** JMAT to sell its catalyst technologies business to Honeywell International HON.O for 1.8 billion pounds ($2.4 billion), including debt

** Co expects deal to deliver net sale proceeds of ~1.6 billion pounds to the group - 88% of which will be returned to shareholders

** Stock on track for its biggest intraday pct gain on record

** Shares up ~35% YTD

($1 = 0.7451 pounds)

(Reporting by Subiksha S in Bengaluru)

((Subiksha.S@thomsonreuters.com;))