摘要:
A high-density, medium-porosity catalyst, supported on a siliceous matrix and based on vanadium, iron, oxygen and alkali metals, wherein the V₂O₅ content ranges from 6 to 9% by weight, the Me₂O content ranges from 8.5 to 12% by weight (Me being an alkali metal), the particle density ranges from 1.10 to 1.40 g/cm³ and furthermore: - the pore volume ranges from 0.20 to 0.70 cm³/g and the surface area ranges from 0.30 to 5 m²/g, the average radius of the pores ranging from 600 to 2200 nm; - the SiO₂ content is at the most 75% by weight and the Fe₂O₃ content is at least 0.90% by weight.
摘要:
A process for preparing 1,2-difluoroethane or 1,1,2-trifluoroethane by hydrogenation of 1,2-dichloro-difluoroethylene or chlorotrifluoroethylene in the presence of a hydrogenation catalyst, said process being conducted in the gas phase at a temperature ranging from 100 to 220°C, the molar ratio of H₂ to olefin being at least 3.
摘要:
Process for the preparation of curable fluoroelastomers comprising reacting from 35 to 80 mol % of vinylidene fluoride, from 15 to 35 mol % hexafluoropropene, from 0 to 30 mol % of another comonomer selected from fluoroolefins and/or perfluorovinyl ethers and from 0.01 to 1 mol % of a brominated fluorovinyl ether having general formula: wherein R 1 is a fluorinated alkylene radical containing from 1 to 9 carbon atoms and n can be either 0 or 1, in the presence of a known polymerization initiator for fluoroelastomers, and of small amounts of a chain-transfer agent having general formula: wherein m is either 1 or 2; when m is 1, R can be either bromine or a perfluoroalkyl radical of 2 to 4 carbon atoms containing a bromine atom bonded to a secondary carbon atom; and when m is 2, R is an alkylene radical of up to 4 carbon atoms containing a bromine atom bonded to a secondary carbon atom.
摘要:
Catalyst suitable for the oxidation of CH 3 OH to CH 2 O, comprising a mixture of a well known catalytic system, herein indicated as mixed oxides, based on Fe 2 (MoO 4 ) 3 and molybdenum trioxide (MoO 3 ) with a quantity of Fe 2 0 3 from 5 to 90% by weight of the sum of Fe 2 O 3 plus mixed oxides, the superficial area of the Fe 2 O 3 being from 1 to 10 m 2 /g and the superficial area of the whole catalyst being from 1 to 6 m 2 /g.
摘要:
Oxetane-structure fluids of well-defined composition and free from not completely fluorinated compounds, characterized in that they have at least a perfluoroether chain bound to an oxetane ring, having improved characteristics for special applications, being liquid up to temperatures of at least -70 °C, having boiling temperatures in the range of from 50° to 270 °C or higher, being the range from the boiling temperatures to the pour point very high.
摘要:
Compositions suitable to be used for washing industrial materials, comprising, by weight:
63 - 98.9% of 1,1,2-trichlorotrifluoroethane; 0.5 - 25% of water; 0.6-12% of a mixture of 80-97% by weight of a compound of formula (I) and of 20-3% by weight of a compound of formula (II); where wherein: R = a C 9 - C 15 alkyl group
A = a C 2 -C 8 aliphatic or cyclic amine, a diamine, or a polyamine; and
1) from 35.5 to 87% by weight of at least a polyolefin 2) from 5 to 20% by weight of an ammonium polyphosphate 3) from 2 to 20% by weight of polycarbonylpiperazine 4) from 2 to 20% by weight of melamine phosphate 5) from 0.5 to 3% by weight of titanium dioxide 6) from 0 to 1.5% by weight of a compound of formula R-SH wherein R is a radical of imidazole or of uracyl.
摘要:
Functional polyolefins containing a terminal functional group; the block copolymers that can be obtained from such polyolefins by reaction with polymers reactive with the functional groups and the precursors used for the preparation of the functionalized polyolefins, which are made up of olefin polymers terminated at one end with Zn R groups where R is an alkyl or aryl radical with 1-10 carbon atoms.