摘要:
The present invention provides a catalytic cracking catalyst for heavy oil and preparation methods thereof. The catalyst comprises 2 to 50% by weight of a phosphorus-containing ultrastable rare earth Y-type molecular sieve, 0.5 to 30% by weight of one or more other molecular sieves, 0.5 to 70% by weight of clay, 1.0 to 65% by weight of high-temperature-resistant inorganic oxides, and 0.01 to 12.5% by weight of a rare earth oxide. The phosphorus-containing ultra-stable rare earth Y-type molecular sieve uses a NaY molecular sieve as a raw material. The raw material is subjected to a rare-earth exchange and a dispersing pre-exchange; the molecular sieve slurry is then filtered, washed with water and subjected to a first calcination to obtain a rare earth sodium Y molecular sieve which has been subjected to such “first-exchange first-calcination”, wherein the steps of rare earth exchange and dispersing pre-exchange are not restricted in sequence; and then the rare earth sodium Y molecular sieve which has been subjected to “one-exchange one-calcination” is subjected to “second exchange and second calcination” including ammonium exchange and a phosphorus modification, wherein the steps of the ammonium exchange and the phosphorus modification are not restricted in sequence. The steps of the ammonium exchange and the phosphorus modification can be conducted continuously or non-continuously, the second calcination is conducted after the ammonium exchange for reducing sodium, the phosphorus modification can be conducted before or after the second calcination. The catalyst provided by the invention has the characteristics of high heavy oil conversion capacity, high total liquid yield, and high yield of light oil.
摘要:
The present invention provides a magnesium-modified ultra-stable rare earth type Y molecular sieve and the preparation method thereof, which method is carried out by subjecting a NaY molecular sieve as the raw material to a rare earth exchange and a dispersing pre-exchange, then to an ultra-stabilization calcination treatment, and finally to a magnesium modification. The molecular sieve comprises 0.2 to 5% by weight of magnesium oxide, 1 to 20% by weight of rare earth oxide, and not more than 1.2% by weight of sodium oxide, and has a crystallinity of 46 to 63%, and a lattice parameter of 2.454 nm to 2.471 nm. In contrast to the prior art, in the molecular sieve prepared by this method, rare earth ions are located in sodalite cages, which is demonstrated by the fact that no rare earth ion is lost during the reverse exchange process. Moreover, the molecular sieve prepared by such a method has a molecular particle size D(v,0.5) of not more than 3.0 μm and a D(v,0.9) of not more than 20 μm. Such a molecular sieve has both high stability and high selectivity for the target product, while cracking catalysts using the molecular sieve as an active component is characterized by a high heavy-oil-conversion capacity and a high yield of valuable target products.
摘要:
The present invention relates to a heavy oil catalytic cracking catalyst having a high yield of light oil and preparation methods thereof. The catalyst comprises 2 to 50% by weight of a magnesium-modified ultra-stable rare earth type Y molecular sieve, 0.5 to 30% by weight of one or more other molecular sieves, 0.5 to 70% by weight of clay, 1.0 to 65% by weight of high-temperature-resistant inorganic oxides, and 0.01 to 12.5% by weight of rare earth oxide. The magnesium-modified ultra-stable rare earth type Y molecular sieve is obtained by the following manner: the raw material, a NaY molecular sieve, is subjected to a rare earth exchange, a dispersing pre-exchange, a magnesium salt exchange modification, an ammonium salt exchange for sodium reduction, a second exchange and a second calcination. The catalyst provided in the present invention is characteristic in its high conversion capacity of heavy oil and a high yield of light oil.
摘要:
In one embodiment, a floating body field-effect transistor includes a pair of source/drain regions having a floating body channel region received therebetween. The source/drain regions and the floating body channel region are received over an insulator. A gate electrode is proximate the floating body channel region. A gate dielectric is received between the gate electrode and the floating body channel region. The floating body channel region has a semiconductor SixGe(1-x)-comprising region. The floating body channel region has a semiconductor silicon-comprising region received between the semiconductor SixGe(1-x)-comprising region and the gate dielectric. The semiconductor SixGe(1-x)-comprising region has greater quantity of Ge than any quantity of Ge within the semiconductor silicon-comprising region. Other embodiments are contemplated, including methods of forming floating body field-effect transistors.
摘要:
A programming method and memory structure for preventing punch-through in a short channel source-side select gate structure includes adjusting voltages on the selected and unselected bitlines, and the program, pass, and select gate voltages.
摘要:
Disclosed is a method of forming memory devices employing halogen ion implantation and diffusion processes. In one illustrative embodiment, the method includes forming a plurality of word line structures above a semiconducting substrate, each of the word line structures comprising a gate insulation layer, performing an LDD ion implantation process to form LDD doped regions in the substrate between the word line structures, performing a halogen ion implantation process to implant atoms of halogen into the semiconducting substrate between the word line structures, and performing at least one anneal process to cause at least some of the atoms of halogen to diffuse into the gate insulation layers on adjacent word line structures.
摘要:
Disclosed is a flash memory device with an enlarged control gate structure, and various methods of make same. In one illustrative embodiment, the device includes a plurality of floating gate structures formed above a semiconducting substrate, an isolation structure positioned between each of the plurality of floating gate structures and a control gate structure comprising a plurality of enlarged end portions, each of the enlarged end portions being positioned between adjacent floating gate structures.
摘要:
Embodiments of a system and method for surgical tracking and control are generally described herein. A system may include a robotic arm configured to allow interactive movement and controlled autonomous movement of an end effector, a cut guide mounted to the end effector of the robotic arm, the cut guide configured to guide a surgical instrument within a plane, a tracking system to determine a position and an orientation of the cut guide, and a control system to permit or prevent interactive movement or autonomous movement of the end effector.
摘要:
A method for producing double-component modified molecular sieve comprises adding molecular sieve to an aqueous solution containing phosphorus to form a mixture, allowing the mixture to react at pH of 1-10, temperature of 70-200° C. and pressure of 0.2-1.2 MPa for 10-200 min, and then filtering, drying and baking the resultant to obtain phosphorus-modified molecular sieve, and then adding the phosphorus-modified molecular sieve to an aqueous solution containing silver ions, allowing the phosphorus-modified molecular sieve to react with silver ions at 0-100° C. in dark condition for 30-150 min, and then filtering, drying and baking. The obtained double-component modified molecular sieve contains 88-99 wt % molecular sieve with a ratio of silica to alumina between 15 and 60, 0.5-10 wt % phosphorus (based on oxides) and 0.01-2 wt % silver (based on oxides), all based on dry matter. A catalyst produced from the double-component modified molecular sieve has improved hydrothermal stability and microactivity.
摘要:
Provided is a phosphorus-containing ultrastable Y-type rare earth (RE) molecular sieve and the preparation method thereof. The method is: based on Na Y molecular sieve as a raw material, obtaining “one-exchange one-roast” RE-Na Y-type molecular sieve through the steps of exchanging with RE, pre-exchanging with dispersing, and the first calcination; and then performing ammonium salt exchange, phosphorus modification, and the second calcination on the “one-exchange one-roast” RE-Na Y-type molecular sieve, wherein the sequence of the RE exchange and the pre-exchange with dispersing is unlimited, and the sequence of the ammonium salt exchange and the phosphorus modification is unlimited as well. The obtained molecular sieve contains RE oxide 1-20 wt %, phosphorus 0.1-5 wt %, and sodium oxide no more than 1.2 wt %, and has a crystallization degree of 51-69% and a lattice parameter of 2.449-2.469 nm. Heavy oil conversion rate can be increased by using the molecular sieve as an active component in a catalytic cracking catalyst.