Abstract:
A process for the treatment of aqueous solutions containing cations and anions, including aluminum sulphate and fluoride ions, for the recovery of the fluorine contained in the aqueous solution by means of an ion exchange plant, in which the aqueous solution flows through at least a strong acid cation-exchanger filter step, then a first weak basic anion-exchanger filter step which produces an almost complete separation of the sulphate ions, and after that a second weak basic anion-exchanger filter step which separates out the fluorine ions, and the fluoride is recovered from an eluate obtained during regeneration of the second anion-exchanger filter step.
Abstract:
A method for inhibiting formation of nitrosamines and an anion exchange resin produced therefrom comprising providing an anion exchange resin with a nitrosating agent and mixing a cation exchange resin with the anion exchange resin to inhibit formation of nitrosamines on the anion exchange resin.
Abstract:
The invention provides a method of reducing the sodium content of a water containing dissolved sodium ions, particularly a water with a sodium ion content of at least 100 ppm. Examples of such waters are effluents such as acid mine drainage and river waters. The method includes the steps of: (i) removing sodium, calcium and magnesium ions from the water by contacting the water with a cation exchange resin/s to capture sodium, calcium and magnesium ions thereon, (ii) treating the cation exchange resin/s of step (i) with nitric acid to produce an eluant containing sodium ions, calcium ions, magnesium ions nitrate ions and nitric acid, (iii) adding a carbonate to the eluant to precipitate the calcium and magnesium ions as calcium and magnesium carbonates; (iv) separating the precipitated carbonates from the eluant; and (v) treating the eluant from step (iv) to obtain a sodium and/or potassium nitrate product.
Abstract:
[Object] To provide a method of purifying nucleic acids where the operation is simple and the nucleic acids can be extracted in a short time with high efficiency.[Solving Means] A method of purifying nucleic acids including the step of adsorbing substances in a sample containing nucleic acids with an ion exchange resin 10 including a positive ion exchange resin and a negative ion exchange resin. As the positive ion exchange resin, a first positive ion exchange resin and a second positive ion exchange resin having an exclusion limit molecular weight lower than that of the first positive ion exchange resin may be used.
Abstract:
The invention provides a method of reducing the sodium content of a water containing dissolved sodium ions, particularly a water with a sodium ion content of at least 100 ppm. Examples of such waters are effluents such as acid mine drainage and river waters. The method includes the steps of: (i) removing sodium, calcium and magnesium ions from the water by contacting the water with a cation exchange resin/s to capture sodium, calcium and magnesium ions thereon, (ii) treating the cation exchange resin/s of step (i) with nitric acid to produce an eluant containing sodium ions, calcium ions, magnesium ions nitrate ions and nitric acid, (iii) adding a carbonate to the eluant to precipitate the calcium and magnesium ions as calcium and magnesium carbonates; (iv) separating the precipitated carbonates from the eluant; and (v) treating the eluant from step (iv) to obtain a sodium and/or potassium nitrate product.
Abstract:
The invention relates to a process for preparing hydroxyl-containing polymers, in particular for preparing polytetrahydrofuran with terminal hydroxyl groups, from the corresponding acyloxy-containing polymers by transesterification with alcohols in the presence of a sodium-containing catalyst. In this process the polytetrahydrofuiran solution is passed in the presence of a catalytic amount of water directly through at least one ion exchanger following the transesterification in order to remove the sodium cations.The novel process makes it possible to remove the sodium cations from the sodium-containing catalyst in an economic manner and with little complexity. The residual sodium content can be reduced to values of less than 0.5 ppm.
Abstract:
There is herein disclosed a method for preparing high-purity aqueous hydrogen peroxide by bringing aqueous hydrogen peroxide into contact with a strongly basic anion exchange resin, said method comprising the step of using the strongly basic anion exchange resin which is converted into a form of an exchange group at the time of the purification of aqueous hydrogen peroxide by bringing the strongly basic anion exchange resin into contact with a liquid agent passed through a filter having an average pore diameter of 1.0 .mu.m or less.According to the present invention, aqueous hydrogen peroxide containing inorganic impurities such as metals and metallic compounds can be purified to prepare extremely high-purity aqueous hydrogen peroxide.
Abstract:
The use of selected cation exchange resins to remove dissolved multivalent cations ions such as iron, zinc, and chromium from used autodeposition compositions permits reuse of the autodeposition compositions without the need for added surfactant and without developing any undesirable graininess or other texture in the coatings formed. Iminodiacetate cation exchange resins are very effective for removing iron ions when they are the only multivalent ions to be removed, and can be efficiently regenerated with 0.5 to 4% by weight aqueous hydrofluoric acid. By proper choice of other cation exchange resins and operating conditions, zinc can be selectively extracted from autodeposition baths containing both iron and zinc, and either iron or zinc can be selectively displaced from the loaded ion exchange resin.
Abstract:
The selectivity of ion exchange processes for the removal of lithium from acids is improved when weak acids such as citric and acetic, are used in the wash step. An added improvement is realized by a two stage process of contacting the acid solution first with an ion exchange resin functional to remove the nickel and aluminum compounds from the acid solution; and then contacting the acid solution with an ion exchange resin which is more selective to remove the alkali metal compound from the acid solution.
Abstract:
A radiator cap assembly for assisting in the removal of coolant from a radiator of an engine is disclosed. The cap has body member with openings at either end and an opening at the side. A conduit extends through the body member. Caps are provided for the traverse opening and another of the openings. A radiator cap member is adapted to secure the body member to a radiator opening.