Abstract: A removal method of manganese in which manganese is removed by precipitating manganese selectively from sulfuric acid waste water containing aluminum, magnesium and manganese with inhibiting the precipitation of magnesium. The removal method of manganese from waste water in which manganese is removed by precipitating manganese selectively from the sulfuric acid waste water containing aluminum, magnesium and manganese with inhibiting the precipitation of magnesium, characterized in that said waste water is subjected to the following steps (1) and (2). (1) First, aluminum in said waste water is removed. (2) Subsequently, neutralizing agent is added into the wastewater after removing aluminum, then pH of the waste water is adjusted at 8.0 to 9.0, and oxygen gas is blown.

Abstract: The method for scrubbing an amine type extractant after stripping to be able to regenerate the same so that the amine type extractant can be repeatedly reused as it is in the extraction stage in the solvent extraction process, when an amine type extractant is regenerated by scrubbing an amine type extractant (A) containing an iron and a zinc chloro complex ion obtained by back extracting a cobalt with a hydrochloric acid aqueous solution from the amine type extractant after extracting a cobalt. The method is characterized by comprising the procedures of the following (1) to (3). (1) an amine type extractant (B) is obtained by adding an aqueous solution containing a sulfite ion to an amine type extractant (A) and stirring the mixture and reducing a ferric (III) chloro complex ion to divalent. (2) an amine type extractant (C) is obtained by adding an aqueous solution containing an oxidizing agent to the amine type extractant (B) and stirring the mixture and oxidizing a sulfite ion to sulfate ion.

Abstract: A method for recovering nickel from an sulfuric acid aqueous solution, for recovering nickel in an effectively utilizable form as a raw material of nickel industry material, by separating efficiently impurity elements of iron, aluminum, manganese and the like, from the sulfuric acid aqueous solution containing nickel and cobalt, and the impurity elements, iron, aluminum, manganese and the like. The method is characterized by comprising the following steps (1) to (5). step (1): to subject the sulfuric acid aqueous solution to oxidation neutralization treatment. step (2): then, to subject the solution to neutralization treatment, and to separate and recover mixed hydroxides containing nickel and cobalt. step (3): to subject the mixed hydroxides to dissolution treatment in a sulfuric acid solution having a concentration of equal to or higher than 50% by mass. step (4): to subject the concentrated solution to solvent extraction treatment, using a phosphate ester-based acidic extraction agent.

Abstract: An impeller blade hub profile which inhibits stall is described. In an embodiment, the hub profile includes a frontal rising contour followed by a rear constant contour. In another embodiment, the hub profile includes a frontal rapidly rising contour followed by a substantially rear constant contour. It was discovered that this combination is much more effective than conventionally known profiles. Also, the present invention provides a unique way of turning the flow within the passages of the rotating impeller blades. In an embodiment, the blade does not turn much over either the front portion of the hub or the rear portion of the hub, but instead turns near the boundary between the front portion and the rear portion.

Abstract: The method for scrubbing an amine type extractant after stripping to be able to regenerate the same so that the amine type extractant can be repeatedly reused as it is in the extraction stage in the solvent extraction process, when an amine type extractant is regenerated by scrubbing an amine type extractant (A) containing an iron and a zinc chloro complex ion obtained by back extracting a cobalt with a hydrochloric acid aqueous solution from the amine type extractant after extracting a cobalt. The method is characterized by comprising the procedures of the following (1) to (3). (1) an amine type extractant (B) is obtained by adding an aqueous solution containing a sulfite ion to an amine type extractant (A) and stirring the mixture and reducing a ferric (III) chloro complex ion to divalent. (2) an amine type extractant (C) is obtained by adding an aqueous solution containing an oxidizing agent to the amine type extractant (B) and stirring the mixture and oxidizing a sulfite ion to sulfate ion.

Abstract: A method for scrubbing an amine-type extractant, in regeneration of the amine-type extractant supporting a chloro complex ion of a metal such as iron and zinc, which easily accumulates in the amine-type extractant, in a scrubbing stage constituting a solvent extraction step, which method is capable of efficiently removing a chloro complex ion of the metal, as well as capable of regenerating extraction capability of an extractant, so that it can be reused repeatedly as it is in the extraction stage of the solvent extraction step.

Abstract: An organic solution of a composition consisting essentially of 100 parts of an indium compound represented by the formulaIn(X).sub.l (Y).sub.mwherein X denotes a chelate ring formed by .beta.-diketones, esters of .beta.-ketoacids or the like, Y denotes an alkoxide formed by aliphatic alcohols or the like, and l and m denote an integer which is either 1 or 2 having the relationship of l+m=3, and from 5 to 20 parts of a tin compound represented by the formulaSn(X').sub.2 or Sn(Y')m'wherein X' denotes a chelate ring formed by .beta.-diketones or esters of .beta.-ketoacids, Y' denotes an alkoxide formed by aliphatic alcohols, and m' denotes 2 or 4, is suitable for deposition of transparent, hardened and low resistivity film coatings of tin-doped indium oxide on a substrate by dipcoating.