摘要:
A method for packing catalysts comprising packing the catalysts having through-holes in the direction of the flow of the gas with plurality of them being arranged in the direction of the flow of the gas through the catalyst-packed layers, characterized by arranging the catalysts in such manner that the sections of the connecting parts in the direction of the flow of the gas do not lie on the same plane as at least one of the above sections of the connecting parts formed by the adjacent catalysts.
摘要:
A molded catalyst for fitting into a reactor vessel having an inlet and an outlet for a reactant gas, the catalyst having openings therethrough parallel to the direction of a reactant gas which is introduced into the reactor vessel from the inlet, the catalyst comprising: a wear-resistant front surface facing the inlet of the reactor vessel and a continuation of the front surface extending therefrom, the both being the front portion of the catalyst, and the remaining part of the catalyst made so wear-susceptible as to have either:(a) a wearability of 2-10% in a shaking abrasion test wherein grinding particles having an average particle size of 100 .mu.m and a Mohs scale of 9 are placed in the openings of the catalyst in an amount of 50% by volume based on the total volume of the openings, and the catalyst is shaked for three hours with an amplitude of 77 mm and a frequency of 320 per minute; or(b) a wearability of 7.5-35% in an air abrasion test wherein an air which contains silica particles having an average particle size of 40 .mu.m in amounts of 70 g/m.sup.3 is passed through in a reactor vessel including a rectangular parallelepipedic catalyst of 45 mm wide, 45 mm thich and 100 mm long so fitted thereinto that the catalyst extends longitudinally in the direction of the flow of the air for 30 min. at a superficial velocity of 40 m/sec. at the front face of the catalyst.
摘要:
A molded catalyst for fitting into a reactor vessel having an inlet and an outlet for a reactant gas, the catalyst having openings therethrough parallel to the direction of a reactant gas which is introduced into the reactor vessel from the inlet, the catalyst comprising: a wear-resistant front portion facing the inlet of the reactor vessel, and the remaining portion of the catalyst made so wear-susceptible as to have either:(a) a wearability of 2-10% in a shaking abrasion test wherein grinding particles having an average particle size of 1000 .mu.m and a Mohs scale of 9 are placed in the openings of the catalyst in an amount of 50% by volume based on the total volume of the openings, and the catalyst is shaken for three hours with an amplitude of 77 mm and a frequency of 320 per minute; or(b) a wearability of 7.5-35% in an air abrasion test wherein an air which contains silica particles having an average particle size of 40 .mu.m in amounts of 70 g/m.sup.3 is passed through in a reactor vessel including a rectangular parallelepipedic catalyst of 45 mm wide, 45 mm thick and 100 mm long so fitted thereinto that the catalyst extends longitudinally in the direction of the flow of the air for 30 min. at a superficial velocity of 40 m/sec. at the front portion of the catalyst.
摘要:
A method is provided for producing a catalyst and a carrier therefor in the form of sheet or honeycomb. The method comprises: beating a heat-resistant fiber such as asbesto fiber in water to form a slurry; mixing the slurry with a catalytically active agent, a carrier material therefor and/or their precursors to fix such materials in the fiber, thus forming a stock; and forming the stock into a sheet and drying the same. The sheet thus obtained may be formed into a honeycomb structure with an improved adhesive.
摘要:
In a method for treating a gas containing dusts therein under a monolithic catalyst consisting of a ceramic support which is substantially porous throughout the structure, and has active ingredients uniformly dispersed therein and passages therethrough parallel to the flow of the gas for allowing the gas to pass therethrough, the improvement in which the catalyst has the sintered front portion or has a vitreous coating on the front portion. Alternatively, the improvement in which a metal or sintered ceramic lid having openings therethrough is fixed onto the front face of the catalyst with the passages in alignment with the openings of the lid.
摘要:
A method is provided for producing a catalyst and a carrier therefor in the form of sheet or honeycomb. The method comprises: beating a heat-resistant fiber such as asbesto fiber in water to form a slurry; mixing the slurry with a catalytically active agent, a carrier material therefor and/or their precursors to fix such materials in the fiber, thus forming a stock; and forming the stock into a sheet and drying the same. The sheet thus obtained may be formed into a honeycomb structure with an improved adhesive.
摘要:
A method is provided for producing a catalytic structure in the form of sheet or honeycomb for the gas phase reduction of nitrogen oxides. The method comprises: beating an inorganic fiber in water to form a slurry; forming the slurry into a sheet by paper-making means and drying the sheet; impregnating the sheet or a honeycomb structure manufactured therefrom which has a porosity of 60-85% with an impregnating slurry which contains titanium dioxide or its precursor in a concentration at least of 100 g/l and has a viscosity of 5-250 cps. at normal temperatures, drying, and when necessary calcining the structure; and then immersing the structure in a solution containing a catalytically active agent or its precursor, drying and calcining the structure, thereby to provide a porous catalytic structure having titanium dioxide and the catalytically active agent substantially uniformly dispersed and supported therein.
摘要:
A method and apparatus for the maintenance of snow quality on an indoor artificial ski slope. The snow quality of the slope, comprising a thin compacted surface layer and a deep unfused base layer, is maintained by promptly managing against the variations of snow quality due to various heat sources. The old surface layer snow is replaced with fresh snow on a daily basis, while deterioration of the snow base layer is prevented by air conditioning and refrigeration means. The old snow is melted, filtered, and used to make new snow, to air condition the slope, and to expedite melting of yet additional old snow.
摘要:
A process for producing a powder material for niobium-containing lead perovskite ceramics represented by the general formula:PbA.sub.x Nb.sub.1-x O.sub.3,wherein X=1/2 or 1/3, A represents at least one element selected from the group consisting of Fe, Co, Cr, Ni, Mn, Mg, Zn, Cd, Zr, In, Cu and Hf. A dried mixture of a sol or a suspension of a hydroxide a component A which has a lower activity than Pb and a niobic acid sol is first calcinated. A Pb compound is then added with the mixture and the resultant mixture is calcinated again.
摘要:
An .alpha.-olefin polymerization catalyst which comprises a perovskite type complex compound comprising a perovskite type compound represented by the formulaABO.sub.3wherein A is at least one element selected from the group consisting of alkaline earth metals and Pb, and B is at least one element selected from the group consisting of Ti, Zr, Hf and Sn; the complex compound further containing at least one oxide of element selected from the group consisting of rare earth elements, transition elements, Bi, Sb and Sn doped in the perovskite type compound in an amount of 0.1-3 mol %.A composite material which comprises the catalyst having an .alpha.-olefin polymer deposited thereon, is useful as, for example, a dielectric ceramic material.