Key points for activating nickel-aluminum alloys
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Nickel-aluminum alloys are used as catalysts in many hydrogenation processes. The topic we are discussing here is the key points for activating nickel-aluminum alloys. First, let me mention a few points: 1) Activation pH of 9.5–10; 2) Activation time of 1 hour; 3) Normal temperature and pressure; 4) Storage pH of 9.5. Please share your opinions so we can discuss this together
Taking all the activation times into account, it is estimated that another hour of heating and refluxing will be required; the storage pH should be 8-9, using soft water
Chemical properties: Before activation, it is a silver-gray amorphous powder that is stable in air; it tends to clump when exposed to water, and it deteriorates easily upon long-term exposure to air； Turns into a black powder after activation ； Catalyst particle sizes: 20–200 mesh, 200–300 mesh; other particle size ranges are available upon customer request ； Bulk density: 500–4000 kg/m3 (depending on the nickel-aluminum ratio). Production method: First, aluminum is melted; when the temperature reaches around 1000°C, nickel powder is added. At this point, due to the heat of fusion, the temperature rises to 1200–1300°C. A graphite rod is used to stir continuously, and the mixture is kept at this temperature for 20–30 minutes. Nickel-aluminum alloy is obtained through cooling, crushing, and grinding. Catalyst activation: At a certain temperature, the catalyst is treated with a sodium hydroxide solution of a specific concentration to dissolve the aluminum in the nickel-aluminum alloy; subsequent washing with water and alcohol, along with passivation, results in an activated catalyst.