Chemical Preparation Of The Process And Properties Of Ultrafine Copper Powder

The superfine copper powder may do the highly effective catalyst, the electric conduction coating, but also may serve as the electric conduction compound material raw material, the electrode material, the chemical additive and so on. The micron level superfine copper powder development is one item possibly brings copper and its the alloy revolutionary nature change essential technology, has the important theory significance and the practical value. This article conducted the research to the chemical process preparation superfine copper powder.We choice ammonia water as the complexing agent. Prepare the copper powder through different reducing agent, we discovers copper powder maked by reducing agent A and reducing agent B surpass other reducing agent in granularity and purity,.Copper powders made by others reducing agent are particle size is large or yield is low.As the reducing agent A price is higher than the reducing agent B, we choice reducing agent B as the reducing agent. Through the orthogonal experiment determines the most superior condition: Reducing agent B concentration 1.25mol/L, the ammonia water 1.5mol, pH=9, temperature 70 ℃, the reaction time 90 minutes. We utilizes the factor experiment carries on the confirmation to the orthogonal experiment result, two results basic are consistent.The superfine copper made in the most superior condition system results in individually grain-size distribution is 2-3 micrometer, the copper powder's resistance is 3.2mΩ per centimeter, yield is 93%. Because of the particle size is little,it is easy to reunite, the granularity accumulation distributes D50 is about 9 micrometer. We try to find a better complexing agent.we performed 3 experiment and find it may make the granularity accumulation distributes D50 is 0.8-1.0 micrometer copper powder, but the cost riase highly,so ammonia water is better one in industrial production.The copper powder make by reducing agents A and B have some oxidation resistance,but if long time preserved is need ,ti need some especial deal with.The use self-restraintcompound oxidation inhibitor carries on anti-oxidized processing to the copper powder,obtains the ideal effect.The copper powder's resistance doesn't change more than 180 days.Expands this experiment to produce 1 kilogram one time, obtains the similar result,but the yield has droped to 86.5%. the granularity accumulation distributes D50 is 9 micrometer. The preparation cost is inexpensive, production cost per kilogram is 238.5 yuan,it has the stronger application value.