摘要:
The present invention provides a fluidized bed reactor and its use for producing olefins from oxygenates, the fluidized bed reactor comprises: a reaction zone located in the lower portion of the fluidized bed reactor and comprising a lower dense phase zone and an upper riser, wherein the dense phase zone and the riser are connected with each other transitionally; a separation zone located in the upper portion of the fluidized bed reactor and comprising a settling chamber, a fast gas-solid separation means, a cyclone and a gas collecting chamber, wherein the riser extends upwardly into the separation zone and is connected at its outlet with the inlet of the fast gas-solid separation means, the fast gas-solid separation means is connected at its outlet with the inlet of the cyclone via a fast gas passage, the cyclone is connected at its outlet with the gas collecting chamber, and the gas collecting chamber is located below the reactor outlet and connected therewith; and a catalyst recycle line for recycling the catalyst from the settling chamber back to the dense phase zone, a catalyst withdrawl line for withdrawing the deactivated catalyst from the settling chamber and/or the dense phase zone to the catalyst regeneration means, and a catalyst return line for returning the regenerated catalyst from the catalyst regeneration means to the dense phase zone.
摘要:
The present invention relates to a way to manufacture carbon nanotubes (CNTs) continuously in a novel nano-agglomerate fluidized-bed and the reactor (NAFBR). It belongs to material and chimical engineering fields. The procedure includes loading transition metal compounds on a support, obtaining a supported catalyst of metal nanoparticles by deoxidization or heater decomposition, catalytic pyrolyzing carbon source gases and vapor depositing of carbon atoms in a NAFBR. CNTs 4∩100 nm in diameter and 0.5∩1000 µm in length have been synthesized on catalyst supports. As the result of a careful choice of the catalysts, as well as the agglomerate structures and size, CNT agglomerates ranged 1∩1000 µm have been smoothly fluidized under 0.005∩2 m/s superficial gas velocity. The bed density is ranged 20∩800 kg/m3 in the NAFBR. This unit is simple and easy to be operated in a high intensity, and it can be used to produce high-purity CNTs with graphitoid walls in high-yield.
摘要:
The present invention relates to a method for continuous production of carbon nanotubes in a nano-agglomerate fluidized bed, which comprises the following steps: loading transition metal compounds on a support, obtaining supported nanosized metal catalysts by reducing or dissociating, catalytically decomposing a carbon-source gas, and growing carbon nanotubes on the catalyst support by chemical vapor deposition of carbon atoms. The carbon nanotubes are 4∼100 nm in diameter and 0.5∼1000 µm in length. The carbon nanotube agglomerates, ranged between 1∼1000 µm, are smoothly fluidized under 0.005 to 2 m/s superficial gas velocity and 20∼800 kg/m 3 bed density in the fluidized-bed reactor. The apparatus is simple and easy to operate, has a high reaction rate, and it can be used to produce carbon nanotubes with high degree of crystallization, high purity, and high yield.