Abstract: Enhanced methods for separating of overlapping density porous materials are provided. The methods of the invention exploit the differences in the porosity of porous feed materials compared to that of the solid plastics. In the first stage, air is forced out of the pores of a porous feed material. In the second stage, a solution, having the appropriate density, is forced into the pores. This increases the density of the porous material relative to the density of the solid plastics. As a result, the porous material can be made to sink, while the solid plastics continue to float.

Abstract: An elutriation column is installed in a separation tank. The elutriation column includes a vertical separation column having a first side feed arm and a second side overflow arm spaced above the first side feed arm. Water is forced upwardly through the vertical separation column at a controllable velocity. A solid feed mixture is fed through the first side feed arm to the vertical separation column. Water from the tank rising in the vertical separation column at the controlled velocity causes targeted floater materials to move upwardly in the vertical separation column and heavier sinker materials to continue to sink. The floater materials flow from an outlet in the side of the separation tank into the recovery tank. At a discharge, lower end of the vertical separation column, the heavier sinker materials are removed from the separation tank. A mechanism is provided for purging undesirable materials that can cause plugging from the feed arm.

Abstract: A method and apparatus are provided for separating elastomeric materials from mixed material streams. A separator includes a bank of parallel rollers extending longitudinally between a first end and a second end. The bank of parallel rollers having a predefined inclination with the first end elevated higher than the second end. Mixed material streams are fed onto a top surface of the high end of the inclined parallel rollers. A material having less friction and elasticity slides down the inclined roller bank top surface are collected into a collection bin positioned adjacent the second, lower end of the roller bank. Other materials having a higher friction coefficient grip the rollers more and are lifted out of the valley due to friction migrating perpendicular to the rotating rollers and are collected in a collection bin positioned adjacent one side of the roller bank parallel to the longitudinal roller axis.

Abstract: An elutriation column is installed in a separation tank. The elutriation column includes a vertical separation column having a first side feed arm and a second side overflow arm spaced above the first side feed arm. Water is forced upwardly through the vertical separation column at a controllable velocity. A solid feed mixture is fed through the first side feed arm to the vertical separation column. Water from the tank rising in the vertical separation column at the controlled velocity causes targeted floater materials to move upwardly in the vertical separation column and heavier sinker materials to continue to sink. The floater materials flow from an outlet in the side of the separation tank into the recovery tank. At a discharge, lower end of the vertical separation column, the heavier sinker materials are removed from the separation tank. A mechanism is provided for purging undesirable materials that can cause plugging from the feed arm.

Abstract: A new method for improving the efficiency of electrodialysis (ED) cells and stacks, in particular those used in chemical synthesis. The process entails adding a buffer solution to the stack for subsequent depletion in the stack during electrolysis. The buffer solution is regenerated continuously after depletion. This buffer process serves to control the hydrogen ion or hydroxide ion concentration so as to protect the active sites of electrodialysis membranes. The process enables electrodialysis processing options for products that are sensitive to pH changes.

Abstract: A method and apparatus are provided for separating elastomeric materials from mixed material streams. A separator includes a bank of parallel rollers extending longitudinally between a first end and a second end. The bank of parallel rollers having a predefined inclination with the first end elevated higher than the second end. Mixed material streams are fed onto a top surface of the high end of the inclined parallel rollers. A material having less friction and elasticity slides down the inclined roller bank top surface are collected into a collection bin positioned adjacent the second, lower end of the roller bank. Other materials having a higher friction coefficient grip the rollers more and are lifted out of the valley due to friction migrating perpendicular to the rotating rollers and are collected in a collection bin positioned adjacent one side of the roller bank parallel to the longitudinal roller axis.

Abstract: A process of washing plastics contaminated with polychlorinated biphenyls (PCBs) is provided to reduce the concentration of the PCBs. A two-step process includes a first washing step using a selected washing solution or solvent, such as, a non-flammable solvent, and followed by a second step using thermal desorption. The two-step process enables reducing the concentration of PCBs in polymers, such as recovered from shredder residue, for example, to as low as 0.253 PPM. One of the preferred solvents is Perchloroethylene.

Abstract: Enhanced methods for separating of overlapping density porous materials are provided. The methods of the invention exploit the differences in the porosity of porous feed materials compared to that of the solid plastics. In the first stage, air is forced out of the pores of a porous feed material. In the second stage, a solution, having the appropriate density, is forced into the pores. This increases the density of the porous material relative to the density of the solid plastics. As a result, the porous material can be made to sink, while the solid plastics continue to float.

Abstract: An improved process for preparing tackifiers and adhesives is an improved energy efficient process for preparing tackifiers, adhesives and dispersions of low-molecular weight polymers and other materials in water. Fine grinding of a low molecular weight polymer is performed to provide the low molecular weight polymer reduced to a selected average particle size in a range between approximately 2.5 ?m and approximately 7.5 ?m with a maximum particle size of less than 10 ?m.

Abstract: A process of washing plastics contaminated with polychlorinated biphenyls (PCBs) is provided to reduce the concentration of the PCBs. A two-step process includes a first washing step using a selected washing solution or solvent, such as, a non-flammable solvent, and followed by a second step using thermal desorption. The two-step process enables reducing the concentration of PCBs in polymers, such as recovered from shredder residue, for example, to as low as 0.253 PPM. One of the preferred solvents is Perchloroethylene.

Abstract: A method and apparatus are provided for separating mixed plastics using flotation techniques including a first stage initial washing tank for washing of incoming plastics and providing a first separation process and at least one separation module. The first stage initial washing tank includes a perforated basket to hold heavy materials, such as metals, glass, and the like. Each separation module includes a separation tank, a feeding section for feeding of mixed stream into the separation tank; and a collecting section for collecting of the separated mixed plastics including floaters and sinkers from the separation tank. The separation tank has no moving parts. Each separation tank and the first stage initial washing tank is a standard off-the-shelf circular tank with a flat bottom. Washing and drying steps are eliminated between separation stages. Batch processing is replaced with generally continuous operation. An integrated vibrating screen and air classification system is provided.

Abstract: Novel musical instrument strings and methods for making the same. Polymer cover combined with a low temperature resin is provided to the strings. Also disclosed are novel plastic materials comprising a film of porous fluoropolymer having UV-cured resin applied to at least a portion of the porosity of the film.

Abstract: A method of separating a portion of acrylonitrile-butadiene-styrene (ABS) from a mixture containing ABS and for separating a portion of ABS and polycarbonate (PC) from a mixture of plastics containing ABS and PC is disclosed. The method includes shredding and/or granulating the mixture of plastics containing ABS and PC to provide a selected particle size; sequentially dispersing the shredded mixture of plastics in a series aqueous solutions having different specific gravities and separating the floating fraction until the desired separation is obtained. Surface tension and pH are also variable to be controlled.

Abstract: A method of separating a portion of acrylonitrile-butadiene-styrene (ABS) from a mixture containing ABS and for separating a portion of ABS and polycarbonate (PC) from a mixture of plastics containing ABS and PC is disclosed. The method includes shredding and/or granulating the mixture of plastics containing ABS and PC to provide a selected particle size; dispersing the shredded mixture of plastics in a first aqueous solution having a specific gravity of 1.04±0.01 g/cc, a pH in the range of 11.5±0.8 and a surface tension of 34±4 dynes/cm wherein a first reject fraction floats and a first retained fraction sinks, separating the first reject fraction from the first aqueous solution, introducing the first retained fraction into a second aqueous solution having a specific gravity of 1.09±0.01 g/cc and a pH in the range of 11.5±0.

Abstract: A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about ¼ inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125° C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

Abstract: The invention is a stretchable layered fabric laminate which is air impermeable and waterproof while being permeable to water vapor. The stretchable fabric laminate includes a stretchable composite material layer consisting of a hydrophobic protective layer of a porous polymeric material on each side of a layer of hydrophilic water-vapor-permeable synthetic polymer. The composite material layer is laminated to at least one layer of stretchable fabric. The stretchable layered fabric laminate has excellent stretch and recovery properties in both machine and transverse directions, and is useful for the manufacture of form-fitting articles of protective clothing and other end uses.

Abstract: A process for removing zinc from galvanized steel. The galvanized steel is immersed in an electrolyte containing at least about 15% by weight of sodium or potassium hydroxide and having a temperature of at least about 75.degree. C. and the zinc is galvanically corroded from the surface of the galvanized steel. The material serving as the cathode is principally a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series.

Abstract: An improved method is provided for separating acrylonitrile butadiene styrene (ABS) and high impact polystyrene (HIPS) plastics from each other. The ABS and HIPS plastics are shredded to provide a selected particle size. The shredded particles of the ABS and HIPS plastics are applied to a solution having a solution density in a predefined range between 1.055 gm/cm.sup.3 and 1.07 gm/cm.sup.3, a predefined surface tension in a range between 22 dynes/cm to 40 dynes/cm and a pH in the range of 1.77 and 2.05. In accordance with a feature of the invention, the novel method is provided for separating ABS and HIPS, two solid thermoplastics which have similar densities by selectively modifying the effective density of the HIPS using a binary solution with the appropriate properties, such as pH, density and surface tension, such as a solution of acetic acid and water or a quaternary solution having the appropriate density, surface tension, and pH.

Abstract: The invention is a stretchable layered fabric laminate which is air impermeable and waterproof while being permeable to water vapor. The stretchable fabric laminate includes a stretchable composite material layer consisting of a hydrophobic protective layer of a porous polymeric material on each side of a layer of hydrophilic water-vapor-permeable synthetic polymer. The composite material layer is laminated to at least one layer of stretchable fabric. The stretchable layered fabric laminate has excellent stretch and recovery properties in both machine and transverse directions, and is useful for the manufacture of form-fitting articles of protective clothing and other end uses.

Abstract: A process and system for treating aluminum salt cake containing water soluble halide salts by contacting the salt cake with water to dissolve water soluble halide salts forming a saturated brine solution. Transporting a portion of about 25% of the saturated brine solution to a reactor and introducing into the saturated brine solution at least an equal volume of a water-miscible low-boiling organic material such as acetone to precipitate a portion of the dissolved halide salts forming a three-phase mixture of an aqueous-organic-salt solution phase and a precipitated salt phase and an organic rich phase. The precipitated salt phase is separated from the other phases and the organic rich phase is recycled to the reactor. The remainder of the saturated brine solution is sent to a multiple effect evaporator having a plurality of stages with the last stage thereof producing low grade steam which is used to boil off the organic portion of the solution which is recycled.