53results about How to "Wide active temperature range" patented technology

The invention discloses a CO selective methanation catalyst and a preparation method thereof, in particular relates to a CO selective methanation catalyst which uses nanometer cerium-zirconium composite oxide as a carrier and a preparation method thereof. The CO selective methanation catalyst comprises an active ingredient Ru and the nanometer cerium-zirconium composite oxide carrier, wherein themol ratio of Ce to Zr is 1-36:6; the content of Ru is 0.2-2 wt% of the catalyst; and the particle diameter of the nanometer cerium-zirconium composite oxide carrier is 5-20nm. The CO selective methanation catalyst has good activity, has high selectivity in the whole reaction temperature area, greatly prevents the unnecessary consumption of hydrogen in reformed gas, and has simple preparation technology and relatively low cost.

The invention discloses a preparation technology of a catalyst used for high temperature catalytic decomposition of N2O. The preparation technology comprises the following steps: dissolving magnesium nitrate, cobalt nitrate, lanthanum nitrate, cerium nitrate, nickel nitrate and zirconium nitrate in water to form a mixed nitrate solution; adding ammonia water and aluminum hydroxide, and carrying out compacting, dehydrating, drying and baking to obtain a powder material; and uniformly rolling the powder material, desalinized water and a bonding agent, drying the rolled materials to obtain a granulation material, compacting the granulation material to form a porous cylinder, and calcining the porous cylinder to obtain the catalyst. The preparation technology has the following advantages: a co-precipitation method is selected, an active component reacts with a carrier substance precursor and a precipitating agent to realize co-precipitation, and the active component interacts with the carrier, so the active component is well and stably dispersed; and the active component and the carrier precipitate are commonly calcined at a high temperature of 1000-1300 DEG C, so the active component of the catalyst has good heat tolerance and difficulty loses, thereby the catalyst has the advantages of high efficiency, good stability and long service life.

The invention is a kind of catalyst purifying method and device for tails of lean firing car. The invention sets two catalyzing reaction beds on the discharging pipe of the engine; there is an additional reducer nozzle in the middle of the two beds. The first bed uses hydrocarbon and carbon monoxide in tails to reduce nitrogen-oxygen compound, at the same time, the hydrocarbon and carbon monoxide are changed into carbon dioxide and water; the second bed uses the additional oxygen hydrocarbon reducer to reduce carbon-oxygen compound, at the same time, the additional reducer is changed into water and carbon dioxide. Compared with current technology scheme, it can spread the range of active temperature, enhances the purifying efficiency, takes advantage of hydrocarbon discharged by the engine and additional oxygen hydrocarbon.

The invention discloses a preparation method of a CO selective methanation catalyst, in particular to a preparation method of a CO selective methanation catalyst using nanometer cerium-zirconium composite oxide as a carrier, which comprises the following steps: dissolving the nitrates of Ce and Zr into water; keeping the pH value within the range from 9 to 13; and then stirring, precipitating, aging and washing; using a drying medium to replace water in the obtained precipitate, and baking the precipitate under the temperature of 300-900 DEG C for 5-8h after being dried; mixing the product and water together, and then being pulverized by ultrasound to obtain suspension liquid; heating and stirring the suspension liquid in the water bath, and then mixing with the precursor of Ru, wherein the pH value is controlled between 9 and 11; fully depositing and precipitating Ru on the product; aging the product at water bath temperature, and then, washing, drying and baking the product under the temperature of 300-900 DEG C for 2-5h; and finally, obtaining the CO selective methanation catalyst. The preparation method has the advantages of simple technology, relatively low cost, good catalyst activity, high strength and high selectivity in the whole reaction temperature area.

The invention relates to a low-temperature sulfur tolerant shift catalyst and a preparation method thereof. The low-temperature sulfur tolerant shift catalyst comprises the following components based on the total weight of the catalyst: 2-6wt% of cobalt oxide, 3-12wt% of molybdenum oxide, 1-15wt% of alkali metal or alkaline-earth metal aids and the balance of a double-peak pore distribution type alumina-based carrier, wherein the carrier consists of gamma-Al2O3, TiO2 and ZrO2; by taking the weight of the carrier as the reference, the content of the gamma-Al2O3 is 56-75wt%, the content of the TiO2 is 3-22wt% and the content of the ZrO2 is 10-22wt%; the pore volume of the catalyst is 0.80-1.20ml / g, and the specific surface area of the catalyst is 100-180m<2> / g; the pore volume with the pore size of less than 50nm in the carrier accounts for 55-65 percent of the total pore volume; the pore volume with the pore size of 150-500nm accounts for 20-30 percent of the total pore volume; and the pore volume with the pore size of more than 500nm accounts for less than 10 percent of the total pore volume. The catalyst is used for a medium-pressure low-temperature sulfur tolerant shift hydrogen production process and has high low-temperature activity, long service life and excellent hydrogen production yield.