SILP materials

Abstract The principle of catalytic SILP materials involves surface modification of a porous solid material by an ionic liquid coating. Ionic liquids are salts with melting points below 100 °C, generally characterized by extremely low volatilities. In the examples described in this paper, the ionic liquid coating contains a homogeneously dissolved Rh-complex and constitutes a uniform, thin film, which itself displays the catalytic reactivity in the system. Continuous fixed-bed reactor technology has been applied successfully to demonstrate the feasibility of catalytic SILP materials for propene hydroformylation and methanol carbonylation. 

In a munber of publications we have recently demonstrated that this problem of mass transport hmitation can be circumvented by using catalytic SILP materials [27-32]. Moreover, these catalysts allow the application of fixed-bed reactors for simple continuous processing when applied in combination with gaseous reaction mixtures making the separation and catalyst recychng obsolete. 

The use of catalytic SILP materials has been reviewed recently [10] covering Friedel-Crafts reactions [33-37], hydroformylations (Rh-catalyzed) [38], hydrogenation (Rh-catalyzed) [39,40], Heck reactions (Pd-catalyzed) [41], and hydroaminations (Rh-, Pd-, and Zn-catalyzed) [42]. Since then, the SILP concept has been extended to additional catalytic reactions and alternative support materials. In this paper we will present results from continuous, fixed-bed carbonylation and hydroformylation reactions using rhodium-based SILP catalysts as reaction examples demonstrating the advantages of the SILP technology for bulk chemical production. 

Additionally, the concept of catalytic SILP materials may be easily combined with several advanced process options providing new opportimities for accomplishing reactions. One attractive approach involves the conductance of consecutive, homogeneous reactions in sequences using several fixed-bed reactors in-series. Another approach involves implementation of integrated reaction-separation techniques using, e.g., SILP-membranes or the use of SILP materials in catalytic distillation processes. 

Rigby J, Kondratenkov M (2004) Arene Complexes as Catalysts. 7 181-204 Riisager A, Fehrmann R, Haumann M, Wasserscheid P (2008) Catalytic SILP Materials. 23 149-161... 

Form an engineering point of view these SILP materials offer some advantages compared to classical gas-Uquid or liquid-liquid systems, especially... 

Considering these benefits, it is estimated that SILP materials will contribute a substantial part of the catalyst and adsorbent markets within the next 10 years. A... 

Figure 4.5 Freeze-drying steps for preparation of SILP materials...

With the growing interest in the SILP technology and the success of these novel materials in catalysis and gas purification, the scale-up of production capacity becomes an important issue. Recently, large batches of SILP materials have been synthesized using fluidized bed spray-coating techniques as shown in Figure 4.7... 

In an attempt to stabilize a higher amount of Pd nanoparticles within the ionic liquid film, Gruttadauria et al. [40] synthesized multilayered SILP materials as... 

The outcome of these measurements with SILP materials based on CPGs of different pore sizes is a melting point depression, which increases with decreasing pore size (Table 8.1). 

Supported Ionic Liquid Phase (SILP) Materials in Hydroformylation Catalysis... 

SILP Materials in Liquid-Phase Hydroformylation Reactions... 

Scheme 15.1 Hydroformylation of 1-hexene catalyzed by anchored SILP materials [7],...

SILP Materials in Liquid-Phase HydroformYlation Reactions 309 Table 15.1 1-Hexene hydroformylation using different reactions systems [7]. 

---