摘要:
Method and equipment for converting hydrocarbon fuel to a mixture of hydrogen and carbon monoxide through catalytic partial oxidation. The catalysts can include a combination of both an oxidation catalyst and a steam reforming catalyst, though no water is used in the process and catalyst contact time is short. Thermal management of the process in the pre-reaction and post reaction zones of the reactor enhance yields and reduce carbon deposition.
摘要:
A ceramic body based on barium and strontium titanates has a composition defined essentially by the formula Ba.sub.1-x Sr.sub.x TiO.sub.3, where x ranges from 0 to 1. The ceramic body is chemically and dimensionally stable in solid oxide fuel cell (SOFC) operation environments, which encounter oxidizing and reducing atmospheres at temperatures as high as 1,000.degree. C. In addition, the ceramic of which the body is comprised can be tailored to yield a ceramic in which the thermal expansion coefficient (CTE) is adjusted between 11.3.times.10.sup.-6 /.degree.C. and 12.4.times.10.sup.-6 /.degree.C. to match the CTE of the other SOFC materials, thereby avoiding the adverse effects of thermal stress. These features make the ceramic body especially suited for use as manifolds in SOFC stacks, or other non-electrical structural components, such as the inflow and outflow gas manifold materials, the stack housing, or other support structure or spacers in the stack, and the like.
摘要:
This invention provides a compound having the formula LnSi.sub.3 N.sub.5 wherein Ln is selected from the group consisting of scandium, yttrium, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. In addition, there is provided a method for making the compound Ln'Si.sub.3 N.sub.5 wherein Ln' is a radical selected from the group consisting of lanthanum, scandium, yttrium, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium, comprising the step of reacting SiO.sub.z, Ln'.sub.x O.sub.y in a nitrogen atmosphere in the presence of carbon at a temperature of from 1200.degree. C. to about 2000.degree. C. for at least 2 hrs., x being an integer equal to or greater than 2, y being an integer equal to or greater than 3, and z being an integer selected from 1 and 2, with the proviso that x and y are selected to result in a stable compound of Ln'.sub.x O.sub.y.
摘要翻译:本发明提供具有式LnSi 3 N 5的化合物,其中Ln选自钪,钇,铈,镨,钕,ium,钐,铕,钆,铽,镝,钬,铒,ium,镱和镥 。 此外,提供了一种制备化合物Ln'Si3N5的方法,其中Ln'是选自镧,钪,钇,铈,镨,钕,ium,钐,铕,钆,铽,镝的基团 钬,铒,ium,镱和镥,包括在碳存在下,在1200℃至约2000摄氏度的温度下,在氮气气氛中使SiO 2,L 1 O 10反应至少2小时的步骤 x是等于或大于2的整数,y是等于或大于3的整数,z是选自1和2的整数,条件是选择x和y以产生稳定的化合物 的Ln'xOy。
摘要:
A sinter-reactive lanthanum chromite powder is prepared from the lanthanum chromite precursor LaCr.sub.1-x M.sub.x O.sub.3 (Adsorbate). The powder is crystalline, has the formula LaCr.sub.1-x M.sub.x O.sub.3, where M is magnesium or calcium and x ranges from about 0.03 to 0.3, and sinters to densities higher than about 95% of theoretical density at temperature as low as 1600.degree. C. in inert or reducing atmospheres. Sintering to such high density at temperatures in the vicinity of 1600.degree. C. makes the powder particularly suited for use as interconnect material for solid oxide fuel cells.
摘要:
A monolithic silicon nitride ceramic is densified at temperatures lower than 2000.degree. C. and heat treated at temperatures greater than 2000.degree. C. in the presence of at least 6.5 w % of multi-component sintering aids. This monolithic silicon nitride has a highly acicular microstructure Chevron Notch fracture toughness greater than 9 MPa.multidot.m.sup.1/2, R-curve behavior, high Weibull modulus, excellent damage tolerance, high thermal conductivity, and other desirable properties.
摘要:
This invention relates to a process for the preparation of a crystalline compound having an empirical formula LaCr.sub.x A.sub.1-x O.sub.4.yH.sub.2 O where A is a metal selected from the group consisting of Mg, Sr, Ca and Ba, x ranges from 0.99 to about 0.7 and y ranges from 0 to 0.15. The process comprises adding a solution of the appropriate metal salts to a solution of ammonium hydroxide thereby precipitating a hydroxide gel intermediate, which is dried and calcined in air to yield the resultant crystalline compound which has a huttonite structure. Additionally, this invention relates to a process for the preparation of a ceramic powder having the empirical formula LaCr.sub.x A.sub.1-x O.sub.3, where A is a metal selected from the group consisting of Mg, Sr, Ca and Ba, and x ranges from 0.99 to about 0.7. Finally, a ceramic composition having the empirical formula LaCr.sub.x A.sub.1-x O.sub.4.yH.sub.2 O having a huttonite structure is also disclosed.