摘要:
The present invention relates to a process for reducing residuals content in a vinyl aromatic polymer, said residuals comprising essentially unpolymerized vinyl aromatic monomer, wherein the vinyl aromatic polymer in the molten state is brought in contact with a solid in powder capable to catalyze the alkylation of said residual vinyl aromatic monomer on the vinyl aromatic polymer. Advantage of the present invention is a sharp reduction of the unpolymerized vinyl aromatic monomer in the vinyl aromatic polymer without generating a new residual and without inducing a colored vinyl aromatic polymer. The present invention also relates to said vinyl aromatic polymer having a low residuals content.
摘要:
The present invention relates to metalloaluminophosphate (MeAPO) molecular sieve with lamellar crystal morphology having an empirical chemical composition on an anhydrous basis, after synthesis and calcination, expressed by the formula HxMeyAlzPkO2 wherein, y+z+k=1 x =10 and advantageously ranges from 10 to 100. In a preferred embodiment T is
摘要:
The present invention concerns binary zeolitic systems comprising two zeolites A and B having different crystalline structures while having common structural units. The crystals of the zeolite A form a central core surrounded by a crown of crystals of zeolite B, the zeolites A and B being disposed concentrically and following the same longitudinal axis. These systems are formed by the introduction of a nucleation gel containing seeds of the zeolite A in a growth gel where the crystallization parameters are favorable to the crystallization of the zeolite B. The binary zeolitic systems are useful as catalysts for transforming hydrocarbons and more especially as cracking catalysts.
摘要:
The present invention relates to a process for the preparation of lauryllactam in which a Beckmann rearrangement of cyclododecanone oxime is carried out. Said process is carried out in the gas phase at a temperature of between 180 and 450° C. in the presence of a microporous material having a three-dimensional inorganic main structure composed of tetrahedra connected via a common edge, called zeolite.
摘要:
The present invention discloses a method for supporting a transition metal complex and the resulting supported catalyst component which is characterised in that the metallic sites are kept away from one another and kept away from the surface of the support.
摘要:
A method is provided for preparing fully lattice-inserted titanium zeolites by post-synthesis processing of the synthetic zeolite optionally containing titanium with an inorganic acid, wherein the post-synthesis processing comprises processing the zeolite in the presence of at least one titanium source with a solution containing at least one oxidizing inorganic acid having a higher redox potential than an acidic tetravalent titanium solution. The invention is also directed to the use of the zeolites.
摘要:
This invention relates to a new zeolite from the class of mazzite, containing a fraction of non-exchangeable potassium cations, and also to a process for its synthesis. The crystallinity and the adsorption capacity of the protonated form of this zeolite are maintained after a prolonged hydrothermal treatment.
摘要:
The invention relates to a process for isomerizing normal paraffins, particularly C.sub.5 -C.sub.6, in the presence of at least one catalyst based on an omega zeolite having a molar ratio SiO.sub.2 /Al.sub.2 O.sub.3 ranging from 6.5 to 80, a content by weight of sodium lower than 0.2%, crystalline parameters "a" and "c" respectively smaller than or equal to 1.814 nm and 0.760 nm, a capacity of adsorption of nitrogen, measured at 77K under a partial pressure of 0.19, higher than about 8% by weight, the catalyst also comprising at least one metal from group VIII of the periodic table of elements, preferably platinum or/and palladium.
摘要翻译:本发明涉及一种在至少一种催化剂存在下使正构烷烃特别是C5-C6异构化的方法,该催化剂基于SiO 2 / Al 2 O 3的摩尔比为6.5至80的ω-沸石,钠的重量比低于 0.2%,分别小于或等于1.814nm和0.760nm的结晶参数“a”和“c”,在77K下在0.19Kg,高于约8%重量下测量的氮吸附容量, 催化剂还包含元素周期表第Ⅷ族中的至少一种金属,优选铂或/和钯。
摘要:
The present invention also relates to a method for preparing metalloaluminophosphate (MeAPO) molecular sieve said method comprising: a) forming a reaction mixture containing a texture influencing agent (TIA), an organic templating agent (TEMP), at least a reactive inorganic source of MeO2 insoluble in the TIA, reactive sources of Al2O3 and P2O5, b) crystallizing the above reaction mixture thus formed until crystals of the metalloaluminophosphate are formed, c) recovering a solid reaction product, d) washing it with water to remove the TIA and e) calcinating it to remove the organic template. In a usual embodiment said reaction mixture has a composition expressed in terms of molar oxide ratios of: TEMP/Al2O3=0.3-5, more desirable 0.5-2 MeO2/Al2O3=0.005-2.0, more desirable 0.022-0.8 P2O5/Al2O3=0.5-2, more desirable 0.8-1.2 TIA/Al2O3=3-30, more desirable 6-20 In a usual embodiment the metalloaluminophosphate (MeAPO) molecular sieves made with the above method have a lamellar crystal morphology having an empirical chemical composition on an anhydrous basis, after synthesis and calcination, expressed by the formula HxMeyAlzPkO2 wherein, y+z+k=1, x
摘要:
The present invention relates to a process for reducing residuals content in a vinyl aromatic polymer, said residuals comprising essentially unpolymerized vinyl aromatic monomer, wherein the vinyl aromatic polymer in the molten state is brought in contact with a solid in powder capable to catalyze the alkylation of said residual vinyl aromatic monomer on the vinyl aromatic polymer.Advantage of the present invention is a sharp reduction of the unpolymerized vinyl aromatic monomer in the vinyl aromatic polymer without generating a new residual and without inducing a colored vinyl aromatic polymer.The present invention also relates to said vinyl aromatic polymer having a low residuals content.