The Collaborative International Dictionary of English v.0.48:

Separative \Sep"a*ra*tive\, a. [L. separativus.]
   Causing, or being to cause, separation. "Separative virtue of
   extreme cold." --Boyle.
   [1913 Webster]

WordNet (r) 3.0 (2006):

separative
    adj 1: (used of an accent in Hebrew orthography) indicating that
           the word marked is separated to a greater or lesser
           degree rhythmically and grammatically from the word that
           follows it
    2: serving to separate or divide into parts; "partitive
       tendencies in education"; "the uniting influence was stronger
       than the separative" [syn: partitive, separative]
    3: (of a word) referring singly and without exception to the
       members of a group; "whereas `each,' `every,' `either,'
       `neither,' and `none' are distributive or referring to a
       single member of a group, `which' in `which of the men' is
       separative"

Moby Thesaurus II by Grady Ward, 1.0:

60 Moby Thesaurus words for "separative":
   ablative, biodegradable, characteristic, characterizing,
   contrastive, corrosive, decomposable, decomposing, degradable,
   diacritical, diagnostic, differencing, differential,
   differentiative, dilapidated, discriminating, discriminative,
   disintegrable, disintegrated, disintegrating, disintegrative,
   disjunctive, disruptive, distinctive, distinguishing, dividing,
   erosive, ethnocentric, exceptional, excluding, exclusive,
   exclusory, idiosyncratic, inadmissible, individualizing,
   individuating, insular, moldering, narrow, parochial, parting,
   peculiar, personalizing, preclusive, prescriptive, preventive,
   prohibitive, ravaged, resolvent, restrictive, ruinous, seclusive,
   segregative, select, selective, separating, snobbish, solvent,
   worn, xenophobic