Abstract: A method for recovering catalytic metals from fluids containing catalytic metal colloids. Fluid compositions such as rinse solutions or dragout baths containing catalytic metal colloids are passed through a filter that entraps catalytic metal colloids on the filter. The catalytic metal colloids have a high affinity for the filter in contrast to other components of the fluids. The other components of the fluids pass through the filter while the catalytic colloids concentrate on the filter. The filter containing the catalytic metal colloids is burned, and the catalytic metal is retrieved. The method is economically efficient and environmentally friendly.

Abstract: A method for recovering catalytic metals from fluid compositions containing catalytic metal colloids. Fluid compositions such as aqueous rinse solutions or dragout baths containing catalytic metal colloids are passed through a porous metal filter that entraps the catalytic metal colloids. The catalytic metal colloids have a high affinity for the porous metal filter in contrast to other components of the fluids. The other components of the fluids pass through the porous metal filter while the catalytic metal colloids concentrate on the porous metal filter. The catalytic metal colloids that are captured on the porous metal filter are removed from the filter by backwashing the filter with a gas and/or a liquid. The backwashing forces the catalytic metal colloids off of the porous metal filter and through a solids discharge valve and into a solids collection container. The method is economically efficient with high catalytic metal recovery and is environmentally friendly.

Abstract: A method for recovering catalytic metals from fluid compositions containing catalytic metal colloids. Fluid compositions such as aqueous rinse solutions or dragout baths containing catalytic metal colloids are passed through a porous metal filter that entraps the catalytic metal colloids. The catalytic metal colloids have a high affinity for the porous metal filter in contrast to other components of the fluids. The other components of the fluids pass through the porous metal filter while the catalytic metal colloids concentrate on the porous metal filter. The catalytic metal colloids that are captured on the porous metal filter are removed from the filter by backwashing the filter with a gas and/or a liquid. The backwashing forces the catalytic metal colloids off of the porous metal filter and through a solids discharge valve and into a solids collection container. The method is economically efficient with high catalytic metal recovery and is environmentally friendly.

Abstract: A method for recovering catalytic metals from fluids containing catalytic metal colloids. Fluid compositions such as rinse solutions or dragout baths containing catalytic metal colloids are passed through a filter that entraps catalytic metal colloids on the filter. The catalytic metal colloids have a high affinity for the filter in contrast to other components of the fluids. The other components of the fluids pass through the filter while the catalytic colloids concentrate on the filter. The filter containing the catalytic metal colloids is burned, and the catalytic metal is retrieved. The method is economically efficient and environmentally friendly.

Abstract: A process for replenishing a tin-lead alloy displacement plating solution which comprises periodically adding complexing agent to the solution during use of the same to bring the total concentration of complexing agent to an amount sufficient to ensure adhesion of the deposit to its underlying substrate.