Shares in ARM were up 3.1 percent at 399.7pence by 0817 GMT, the top riser in the FTSE 100 index (.FTSE), and setting aeight-year high for the second consecutive day.
The perfermance test on a commercial riser cracker shows that meta-Y-3A molecular sieve cracking catalyst is of high activity and improved gasoline selectivity.
The causes behind breakage of the catalyst are excessive sodium and vanadium content in the feed oil, excessively high regeneration temperature and excessively high steam velocity in riser pipe.