Abstract: A photo-chemical remediation of Cu-CMP waste streams basically includes the following acts: adding photo-catalyst particles into waste streams containing copper ions and organic pollutants and exposing the waste streams to UV light or sunlight to make copper ions become deposited on surfaces of the photo-catalyst particles. Whereby, the copper ions are removed from the waste streams. Meanwhile, organic and inorganic pollutants are decomposed by the photolysis capability of the photo-catalyst to make the waste streams dischargable within environmental standards to the environment.

Abstract: The present invention relates to a method for treating spent tin or tin/lead stripping solution used in the electronic industry, particularly in the manufacture of printed circuit boards or a lead frames. Said method comprises (i) electrolytically reducing copper ions in the solution to copper at a low temperature; (ii) electrolytically oxidizing Sn2+ and Pb2+ in the solution at a high temperature to form solid tin and lead oxides and hydroxides; (iii) separating solid tin and lead oxides and hydroxides from the solution; (iv) dissolving tin and lead oxides and hydroxides obtained in step (iii) in a strong alkali or acidic solution; and (v) electrolytically reducing the alkali or acidic solution obtained in step (iv) at a high temperature to recover metallic tin and lead. Also, the filtrate obtained in step (iii) above is useful for preparing fresh tin or tin/lead stripping solution.

Abstract: A process of directly plating onto a nonconductive substrate is disclosed. The process comprises the steps of:1) conditioning: modifying a surface of the nonconductive substrate with selected organic hydrocarbons or polymers to enhance its property of adsorbing catalysts;2) catalyzing: immersing the conditioned substrate into a catalyst colloid-containing solution or a catalyst complex-containing solution to let the catalyst be adsorbed onto the substrate;3) accelerating: reducing the catalyst with a suitable acid or basic solution (adapted to the catalyst colloid), or with a reducing agent (adapted to the catalyst complex) to reduce the catalyst being adsorbed onto the substrate;4) enhancing: immersing the substrate after accelerating step into an enhancing agent containing a compound with two ligands;5) electroplating: proceeding with a plating process.