35results about How to "Environmental recycling" patented technology

The present invention solves an existing technical serious problem in which it is impossible to electrochemically recover heavy rare earth metals from waste including heavy rare earths due to low reduction potential. The present invention adds a complexing agent to industrial waste including the heavy rare earth metals; thereby forming a heavy rare earth metal ion-ligand complex compound between heavy rare earth metal ions and the complexing agent, and metalizes and recovers the heavy rare earth metal ions through an electrochemical method, thus being able to recover environmentally friendly heavy rare earth metals at a high recovery rate from the industrial waste including the heavy rare earth metals.

The invention discloses a preparation method of an asymmetric-structure pre-oxidized metal filter material for a gas turbine. The preparation method includes preparing perovskite-type substance Ab1-xCxO3 powder, degreasing the powder in a vacuum furnace, coating a metal net base material with a composite adsorption material, putting the metal net base material into the vacuum furnace, sintering the metal net base material at the temperature of 1000-1600 DEG C for 10-30 hours to obtain a composite support layer, performing ball milling on the perovskite-type substance to obtain sizing agent, coating the composite support layer with the sizing agent, drying the composite support layer and sintering the same at the temperature at 900-1500 DEG C, taking out the composite support layer after cooling to obtain a semi-finished asymmetric-structure pre-oxidized metal filter material, rolling the prepared semi-finished filter material to be tubular by a forming machine, and welding a center seam of the tubular filter material by an argon arc welding machine or plasma welding machine to obtain the asymmetric-structure pre-oxidized metal filter material. The prepared asymmetric-structure pre-oxidized metal filter material for the gas turbine has the advantages of low filtration resistance, large filtration flux, high porosity and high pressure bearing capacity.

The invention discloses a lead compound nano-powder preparation method for recovery and manufacture of lead-acid battery. The lead compound nano-powder preparation method comprises the following steps that 1, lead, a lead salt or waste lead-acid battery lead paste reacts with one or more organic or inorganic compounds to produce a soluble lead salt solution or a lead hydroxide solution; 2, one or more alkalis or caustic alkalis are added into the soluble lead salt solution, or a part or excess amount of H2CO3 or CO2, sulfuric acid, one or more organic acids or their salts are added into the lead hydroxide solution, and 3, lead oxide or lead hydroxide precipitates obtained by the step 2 are filtered and are subjected to drying and pyrolysis to form the lead compound nano-powder. The lead compound nano-powder preparation method realizes environmentally friendly recovery and production, has low energy consumption, greatly reduces a production cost, and shortens a production period. The lead compound nano-powder obtained by the lead compound nano-powder preparation method is conducive to improvement of technical product performances.