Abstract: This invention comprises a process for separating 2,4-toluene diisocyanate from a feed mixture with 2,6-toluene diisocyanate. The process comprises contacting the mixture at adsorption conditions with an adsorbent comprising a Y-type zeolite cation exchanged with a cation in the group Na, Ca, Li or Mg, thereby selectively adsorbing the 2,4-toluene diisocyanate. The remainder of the feed mixture is removed from the adsorbent and the adsorbed toluene diisocyanate isomer is recovered by desorption at desorption conditions with a desorbent material comprising toluene.

Abstract: Methyl isocyanate can be separated in high yields from a gas-phase mixture of the isocyanate and water by sequentially condensing a major portion of the water, adsorbing essentially all the remaining water from the mixture, and liquefying the methyl isocyanate.

Abstract: Disclosed is a process for reducing the acid content and thereby increasing the reactivity of a polymethylene polyphenylisocyanate which comprises contacting said polyisocyanate with an effective amount of a poly(N-vinylimidazole).

Abstract: Isocyanates produced by vapor-phase catalytic oxidative dehydrogenation of corresponding N-substituted formamides are readily separated from by-product water by contacting the reaction mixture, in the vapor phase, with a cold brine mixture comprising water and about 25% to about 35% by weight of a salt or salts selected from the group consisting of NaCl, CaCl.sub.2, and MgCl.sub.2, the brine mixture having been maintained at a temperature between about 0.degree. C. and its freezing point prior to contact with the reaction mixture containing isocyanates.

Abstract: A process for producing an aliphatic isocyanate from an aliphatic primary amine comprising a carbonylation step in which an aliphatic primary amine is allowed to react with carbon monoxide at a temperature of about 100.degree.-250.degree. C. in the presence of an aromatic hydroxyl compound having a pKa value of not more than about 11, molecular oxygen and a catalyst system comprising at least one member selected from palladium and rhodium metals and components thereof and at least one member selected from iodine and bromine and compounds thereof and a combined separation and recovery step comprising a pyrolysis-distillation reaction in which the mixture of carbonylated products is heated to a temperature of from about 100.degree. to 300.degree. C.