Isocyanates, Organic

Abstract

The article contains sections titled: 1. Introduction 2. Physical Properties 3. Chemical Properties 4. Production 4.1. Phosgenation of Free Amines 4.2. Other Phosgenation Procedures 4.3. Non‐Phosgene Processes 5. Environmental Protection 6. Quality Specifications and Analysis 7. Storage and Transportation 8. Uses 9. Economic Aspects 10. Toxicology and Occupational Health

Material development and process optimization for gas-phase hydrogen chloride electrolysis with oxygen depolarized cathode

“…Over two-thirds of all chemical products have a direct or indirect connection to chlorine [2]. Some important processes in the polymer industry use chlorine as reactant which is finally completely converted to hydrogen chloride (HCl) [3]. Here, HCl is a waste product which needs to be recycled or used for other purposes.…”

Carbon2Polymer – Chemical Utilization of CO2 in the Production of Isocyanates

“…The oxidative carbonylation of primary aromatic amines to generate the corresponding carbamates is well known , and is also the key step from TDA to TDC in the alternative (CO 2 ‐based) route towards TDI as high‐value polymer precursor (Scheme ). Apart from this, the synthesis of TDC via reductive carbonylation of nitro compounds and reactions of amines with organic carbonates , CO 2 or corresponding ureas with alcohols are competing concepts – but do not address our needs in such a completive way.…”

“…The selective cleavage of carbamates to yield isocyanates is a promising non‐phosgene route . Nevertheless, this dealcoholysis reaction faces three major challenges: 1) The reaction is equilibrium‐limited, 2) highly endothermic and 3) the formed isocyanates easily undergo consecutive reactions depleting the yield.…”

Carbon2Polymer – Conceptual Design of a CO2‐Based Process for the Production of Isocyanates

“…The desired TDI is obtained from the purified TDC by cleavage , which can be considered as the reverse urethane reaction : …”

“…Polyether polyols, the most widely used oligomer polyols in PUR production, are currently obtained from propylene oxide and ethylene oxide , which in turn are produced from fossil resources . Isocyanates are conventionally produced from diamines by treatment with the fossil‐based substance phosgene .…”