Towards an industrial synthesis of diamino diphenyl methane (DADPM) using novel delaminated materials: A breakthrough step in the production of isocyanates for polyurethanes

Abstract

ElsevierBotella Asuncion, P.; Corma Canós, A.; Carr, RH.; Mitchell, CJ. (2011). Towards an industrial synthesis of diaminodiphenylmethane (DADPM) using novel delaminated materials: A breakthrough step in the production of isocyanates for polyurethanes. Applied Catalysis A: General. 398(1):143-149. doi:10.1016/j.apcata.2011.03.026. AbstractDelaminated materials ITQ-2, ITQ-6 and ITQ-18 are very efficient catalysts of zeolitic nature for the synthesis of diamino diphenyl methane (DADPM), the polyamine precursor in the production of MDI for polyurethanes. The exfoliation process results in excellent accessibility of their active sites to reactant molecules as well as fast desorption of products. These catalysts present higher activity and slower rates of deactivation than their corresponding zeolites. Moreover, the topology of the delaminated structure imposes a precise control of the isomer distribution, offering an additional flexibility in the synthesis of DADPM. By optimizing the process conditions it is possible to achieve final DADPM crude under industrial production specifications with ITQ-18. This catalyst represents a real chance for replacing HCl in the industrial production of DADPM.

Layered zeolitic materials: an approach to designing versatile functional solids

“…111,112,113 The physico-chemical and textural properties linked to highly accessible delaminated ITQ-2 zeolites were also positive to carry out reactive processes with industrial application such as the synthesis of diaminophenylmethane (DADPM), i. e. the polyamine precursor in the production of methylene diphenylene diisocyanate (MDI) for polyurethanes generation. 114,115,116 Moreover, the open structure of exfoliated materials was used for methanol to olefins conversion (MTO) and dehydrogenation of propane to propylene in presence of CO 2 over ITQ-2 supported gallium oxide. 117,118 ITQ-2 also gave excellent results for hydrocracking, and for hydrotreating light cycle oil (LCO) fractions, being the MWW delaminated catalysts supported with Ni-Mo and Pt species excellent for mild hydrocracking (MHC) of vacuum gas oil and aromatic hydrogenation due to the combination of the efficient activity of zeolites with the desired selectivity of metallic catalysts.…”

Synthesis of 4,4′-Methylenedianiline Catalyzed by SO3H-Functionalized Ionic Liquids

“…The experimental results show that this step needs an acidic catalyst, but the acidity of catalyst is not important because there was little difference in the conversion of aniline over different SFILs. The yield and selectivity of 4,4′-MDA, however, decreased in the following order: [HSO 3 3 -bmim]CCl 3 COO. The difference in the catalytic performance of the SFILs might result from their different acidity.…”

Insight into the mechanism of 3,3′-dimethyl-4,4′-diaminodiphenylmethane synthesis over Hβ zeolite

“…Therefore, there is great academic interest and practical importance to develop easily separable, highly active and reusable solid acids to replace mineral acids for the synthetic process of diaminodiphenylmethanes [1,12]. When the uses of heterogeneous catalysts for MDT synthesis is scarcely disclosed in the literature, several solid acids including ion-exchanged resins [13], metallic compounds [14][15][16][17], clays [11,18], and zeolites [1,[19][20][21][22] have been tested for the synthesis of 4,4'-diaminodiphenylmethane (MDA) by condensation of anilines and formaldehyde.…”