Magnetic solvent extraction

Particles of a magnetic material coated with a hydro- phobic surfactant are dispersed in an organic solvent extractant to produce a magnetic solvent extractant which can be used in solvent extraction processes. Phase separation of an organic phase, carrying the component to be separated, from the aqueous phase can be accelerated by applying a magnetic field to the organic phase. After removal of the organic phase, a magnetic field can be applied to the aqueous phase to remove any residual organic phase and thereby enhance the degree of separation.https://digitalcommons.mtu.edu/patents/1086/thumbnail.jp

Method of magnetizing nonmagnetic materials

Particles of a nonmagnetic material are rendered magnetic by contacting their surfaces with a magnetizing reagent comprising water containing particles of a magnetic material, each of which has a two layer surfactant coating including an inner layer and an outer layer. The inner layer covers the magnetic particle and is a mono- molecular layer of a first water soluble, organic, hetero- polar surfactant containing at least 3 carbon atoms and having a functional group on one end which bonds with the magnetic particle. The outer layer coats the inner layer and is a monomolecular layer of a second water soluble, organic heteropolar surfactant containing at least three carbon atoms and having a hydrophobic end bonded to the hydrophobic end of the first surfactant and a functional group on the other end capable of bonding with the particles to be magnetized.https://digitalcommons.mtu.edu/patents/1095/thumbnail.jp

Wet process for fly ash beneficiation

A wet process for the beneficiation of a fly ash by-product has the following steps: a) forming a slurry mixture of a fly ash material and a liquid; b) gravitationally separating and collecting a first material fraction of the fly ash having a density less than the liquid by skimming off floating slurry material; c) separating a first magnetic fraction from the slurry by subjecting the slurry to a magnetic field of from about 300 gauss to about 10 kilogauss; d) separating the unbumed carbon from the remaining slurry components by adding an effective amount of an oil having a carbon chain greater than octane, and a frothing agent whereby the oil coats the unbumed carbon forming hydrophobic carbon materials and inducing air into the system for frothing the slurry mixture wherein the hydrophobic unbumed carbon froths to the surface and is removed by skimming off the frothing layer; and e) collecting the remaining fraction of silicate spheres and silicates.https://digitalcommons.mtu.edu/patents/1078/thumbnail.jp

Froth flotation apparatus

The froth flotation apparatus includes a gas bubble-particle contact unit including a mixing structure for breaking a gas into fine bubbles,such as a packed tower packing or mechanical agitator, and a separate phase separation unit. A conditioned aqueous pulp containing a mixture of hydrophobic and hydrophilic particles and a substantially inert gas, such as air, are introduced into and combined in one end of the contact unit and subsequently flow concurrently through the mixing structure, such that the gas is broken into fine bubbles which intimately contact and become attached to the hydro- phobic particles. The resulting gas bubble-particle mixture is introduced into the phase separation unit which is operated under substantially quiescent conditions. A concentrate fraction containing primarily hydrophobic particles and a tailing containing primarily hydrophilic particles are discharged from the upper and lower portions of the phase separation unit, respectively. In one embodiment, the phase separation unit comprises a vertical column including one or more slowly rotating paddles in the froth zone to produce a froth having a substantially uniform buoyancy. In another embodiment, the phase separation unit comprises an elongated, generally horizontal tank and includes a skimming assembly for moving froth toward the concentrate fraction outlet.https://digitalcommons.mtu.edu/patents/1077/thumbnail.jp

Method for removal of ammonia from fly ash

A method for removing ammonia and ammonia compounds from fly ash and other combustion by-products is provided. The method may be performed with raw or processed fly ash, or it may be performed in conjunction with a wet beneficiation process. The method involves mixing the ammonia-contaminated fly ash with water and then filtering and/or drying the solution to remove the ammonia and water. The method produces fly ash having an ammonia content of less than about 60-80 ppm, which allows the fly ash to be utilized in a number of applications.https://digitalcommons.mtu.edu/patents/1061/thumbnail.jp

Reagents for magnetizing nonmagnetic materials

Particles of a nonmagnetic material are rendered magnetic by contacting their surfaces with a magnetizing reagent comprising water containing particles of a magnetic material, each of which has a two layer surfactant coating including an inner layer and an outer layer. The inner layer covers the magnetic particle and is a mono- molecular layer of a first water soluble, organic, hetero- polar surfactant containing at least 3 carbon atoms and having a functional group on one end which bonds with the magnetic particle. The outer layer coats the inner layer and is a monomolecular layer of a second water soluble, organic heteropolar surfactant containing at least three carbon atoms and having a hydrophobic end bonded to the hydrophobic end of the first surfactant and a functional group on the other end capable of bonding with the particles to be magnetized.https://digitalcommons.mtu.edu/patents/1096/thumbnail.jp

Froth flotation

A froth flotation apparatus includes a gas bubble-particle contact unit including a mixing means for breaking a gas into fine bubbles, such as a packed tower packing or mechanical agitation means, and a separate phase separation unit. A conditioned aqueous pulp containing a mixture of hydrophobic and hydrophilic particles and a substantially inert gas, such as air, are introduced into one end of the contact unit and flow concurrently through the mixing means, such that the gas is broken into fine bubbles which intimately contact and become attached to the hydrophobic particles. The resulting gas bubble-particle mixture is introduced into the phase separation unit which is operated under substantially quiescent conditions. A concentrate fraction containing primarily hydrophobic particles and a tailing containing primarily hydrophilic particles are discharged from the upper and lower portions of the phase separation unit, respectively. In one embodiment, the phase separation unit comprises a vertical column including one or more slowly rotating paddles in the froth zone to produce a froth having a substantially uniform buoyancy. In another embodiment, the phase separation unit comprises an elongated, generally horizontal tank and includes a skimming assembly for moving froth toward the concentrate fraction outlet.https://digitalcommons.mtu.edu/patents/1084/thumbnail.jp

Wet process for fly ash beneficiation

A wet process for the beneficiation of a fly ash by-product has the following steps: a) forming a slurry mixture of a fly ash material and a liquid; b) gravitationally separating and collecting a first material fraction of the fly ash having a density less than the liquid by skimming off floating slurry material; c) separating a first magnetic fraction from the slurry by subjecting the slurry to a magnetic field of from about 300 gauss to about 10 kilogauss; d) separating the unburned carbon from the remaining slurry components by adding an effective amount of an oil having a carbon chain greater than octane, and a frothing agent whereby the oil coats the unburned carbon forming hydrophobic carbon materials and inducing air into the system for frothing the slurry mixture wherein the hydrophobic unburned carbon froths to the surface and is removed by skimming off the frothing layer; and e) collecting the remaining fraction of silicate spheres and silicates.https://digitalcommons.mtu.edu/patents/1085/thumbnail.jp

Control of mercury emissions using unburned carbon from combustion by-products

Mercury emission from a flue gas such as that generated by a coal fired power plant is controlled by injecting into the flue gas unburned carbon purified from ash such as fly ash or wood ash. The unburned carbon adsorbs the mercury and is later removed from the flue gas by a particle separator. The unburned carbon collected from ash is significantly lower in cost compared to activated carbon presently used in such a process. The unburned carbon is concentrated in the sorbent by one or more separation processes used to remove noncarbon particles from the fly ash. These processes include gravity separation, electrostatic separation, froth flotation, magnetic separation and size classification. Mercury adsorption is further increased by oxidation of the carbon surface.https://digitalcommons.mtu.edu/patents/1066/thumbnail.jp

A Study of the Microscopic Characteristics of Fracture Surface of MDI-Bonded Wood Fiber/Recycled Tire Rubber Composites Using Scanning Electron Microscopy

Scanning electron microscopy (SEM) was utilized to observe the microstructure and fracture surfaces of tensile, bending, and internal bonding specimens of diphenylmethane diisocyanate (MDI) bonded wood fiber/recycled tire rubber composites. Microscopic characteristics of the composites, such as interface bonding between fibers and between fiber and rubber, geometry changes of wood fibers and rubber crumbs, and density profile along the thickness direction of composites, were examined. Four fracture types were classified by the observation of micrographs of various samples: fiber pull-out, fiber breakage, fiber partial pull-out and then breakage, and fiber split. The effects of two important factors, fiber to rubber ratio and MDI level, on bonding quality and fracture type were studied. The results illustrated that excellent bonding was formed between fibers, and good bonding was also observed between fiber and rubber in the micrographs. The degree of wood fiber densification varies along the thickness direction of the composites, forming a density profile. Fiber-slippage and density profile formed during the hot-press process give the composite a layerlike structure. Fiber breakage often occurs in high-densified layers or the layers with high resin content. Fiber pull-out often occurs in low-densified layers or the layers with low resin content