The 1-(2,6-dibenzhydryl-4-nitrophenylimino)-2-mesityliminoacenaphthylnickel bromide (1) is supported on the silica modified by adding different aluminum compounds. The immobilized catalysts show high activities toward ethylene polymerization being initiated by the co-catalyst either (Bu3Al)-Bu-i or Et2AlCl. The resultant polyethylenes display moderate branching (30-50 CH3/1000C) along with high molecular-weights (up to 1.5 x 10(6)g mol(-1)) as well as narrow molecular weight distributions (2.1-2.4). The kinetic study of immobilized catalysts has been conducted and compared with that of homogeneous 1/Et2AlCl system. The supported nickel catalysts produce spherical particles of branched PEs at slurry polymerization without reactor fouling and could be practically attractive. (C) 2019 Elsevier Inc. All rights reserved.