A method for preparing high purity alumina (HPA) is provided. The method includes subjecting an aluminum feedstock to acid leaching, thereby yielding an aluminum bearing leachate; subjecting the aluminum bearing leachate to solvent extraction, thereby yielding an organic phase which is loaded with aluminum; stripping the aluminum from the loaded organic phase with a stripping solution containing an acid, thereby yielding an aluminum bearing extract; crystallizing an aluminum salt from the aluminum bearing extract; dissolving the aluminum salt in an ammoniacal solution, thereby generating a boehmite precursor compound and an ammonium salt; calcining the boehmite precursor compound to yield HPA; subjecting the ammonium salt to electro-dialysis, thereby yielding ammonia and the acid; and performing at least one step of (a) utilizing the ammonia in preparing the ammoniacal solution used in a subsequent iteration of the method, or (b) utilizing the acid in preparing the stripping solution used in a subsequent iteration of the method.

A process of making ammonium nitrate from nitric acid and ammonia in a tubular reactor internally coated with a ceramic coating.

Provided is a novel production system for a product selected from a nitrogen-containing product and a fermented and cultured product that does not involve (or can minimize) the transport of liquid ammonia. A production system for a product selected from a nitrogen-containing product and a fermented and cultured product can include: an ammonia synthesis apparatus in which an ammonia-containing gas is synthesized by reaction of a source gas containing hydrogen and nitrogen in the presence of a supported metal catalyst containing as a support one or more selected from the group consisting of: i) a conductive mayenite compound; ii) a two-dimensional electride compound or a precursor thereof; and iii) a complex formed of a support base containing at least one metal oxide selected from ZrO.sub.2, TiO.sub.2, CeO.sub.2, and MgO and a metal amide represented by a formula M(NH.sub.2).sub.x (where M represents one or more selected from Li, Na, K, Be, Mg, Ca, Sr, Ba, and Eu; and x represents a valence number of M) supported by the support base; and a production apparatus that produces a product selected from a nitrogen-containing product and a fermented and cultured product using ammonia originating from the ammonia-containing gas obtained by using the ammonia synthesis apparatus.

The invention provides a method and a plant for producing urea ammonium nitrate (UAN). The method involves the use of a condensation section, optionally in combination with a medium pressure decomposition section, between the dissociation and neutralization sections. The invention further provides a method of modifying an existing UAN plant. The advantages of the process of the invention are that the emission of CO.sub.2 can be reduced, the plant capacity can be increased and the high capital expenditure needed for CO.sub.2 compression equipment is reduced.

A method for preparing high purity alumina (HPA) is provided. The method includes subjecting an aluminum feedstock to acid leaching, thereby yielding an aluminum bearing leachate; subjecting the aluminum bearing leachate to solvent extraction, thereby yielding an organic phase which is loaded with aluminum; stripping the aluminum from the loaded organic phase with a stripping solution containing an acid, thereby yielding an aluminum bearing extract; crystallizing an aluminum salt from the aluminum bearing extract; dissolving the aluminum salt in an ammoniacal solution, thereby generating a boehmite precursor compound and an ammonium salt; calcining the boehmite precursor compound to yield HPA; subjecting the ammonium salt to electro-dialysis, thereby yielding ammonia and the acid; and performing at least one step of (a) utilizing the ammonia in preparing the ammoniacal solution used in a subsequent iteration of the method, or (b) utilizing the acid in preparing the stripping solution used in a subsequent iteration of the method.

Some embodiments of the disclosure pertain to a plant and a process for producing a urea-containing product. The plant comprises a medium pressure dissociation unit and a high pressure CO.sub.2 stripper each receiving a part of the urea synthesis solution. Stripped urea solution is further treated in a medium pressure treatment unit.

Methods and systems are provided, which convert spent electrolyte from aluminum-air batteries into high purity alumina (HPA) and useful co-products such as fertilizer(s) and/or feed supplement(s). Aluminum tri-hydroxide (ATH) having potassium (K) and/or sodium (Na) impurities, e.g., from spent electrolyte, may be dissolved in strong acid to form an acidic ATH solution having pH<4. Consecutively, the acidic ATH solution may be neutralized to pH>4 to precipitate ATH while retaining dissolved K/Na in the neutralized solution. The dissolving and the neutralizing may then be repeated with the precipitated ATH until a specified purity level of the precipitated ATH is reached. Using appropriate bases to neutralize the acidic ATH solution, e.g., ammonia and/or choline, yields useful co-products such as ammonium nitrate (with nitric acid as the strong acid) and choline chloride (with hydrochloric acid as the strong acid), respectively.

The present disclosure is generally directed to a water processing system. In some embodiments, the water processing system may be configured to generate a potassium salt, such as potassium nitrate, an ammonium salt, such as ammonium nitrate, or both. In some embodiments, the water processing system may be at least partially powered by renewable energy, such as by using a liquid storage system that is at least partially underground. In some embodiments, the water processing system may be configured to reuse certain greenhouse emissions to improve performance of power generation systems associated with the water processing system.

A method for preparing urea ammonium nitrate solution from waste nitric acid after stripping tin from circuit board includes: causing the waste nitric acid after stripping tin and the ammonia water to undergo neutralizing and precipitating reaction through acid-base neutralization, filtering, thereby obtaining tin-containing filter mud and a primary filtrate; adding iron powders into to the primary filtrate to initiate copper-iron replacement reaction, filtering, thereby obtaining iron-containing coarse copper powders and a secondary filtrate; adding hydrogen peroxide to the secondary filtrate, filtering, thereby obtaining an iron-containing sludge and a tertiary filtrate; adding a heavy metal capturing agent to the tertiary filtrate, filtering, thereby obtaining a heavy metal sludge and an ammonium nitrate solution; measuring a concentration of the ammonium nitrate solution, adding urea and liquid fertilizer corrosion inhibitor to obtain a urea/ammonium nitrate dilute solution, evaporating and concentrating the urea/ammonium nitrate dilute solution, thereby obtaining the urea ammonium nitrate solution.

A method for preparing a cathode active material precursor for a secondary battery, including: moving a co-precipitation filtrate generated after a co-precipitation reaction to a co-precipitation filtrate storage tank; removing a metal hydroxide by passing the co-precipitation filtrate through a filter; reacting the co-precipitation filtrate from which the metal hydroxide is removed with sulfuric acid or nitric acid to produce an ammonium sulfate or an ammonium nitrate while removing ammonia from the co-precipitation filtrate from which the metal hydroxide is removed; cooling and crystallizing the co-precipitation filtrate from which the metal hydroxide and ammonia are removed to precipitate a sodium sulfate; filtering the precipitated sodium sulfate to separate the precipitated sodium sulfate from the co-precipitation filtrate from which the metal hydroxide and ammonia are removed; drying the sodium sulfate separated from the co-precipitation filtrate and moving the co-precipitation filtrate separated from the sodium sulfate to a circulation concentration tank; and heating the co-precipitation filtrate stored in the circulation concentration tank to a predetermined temperature for recycling and performing N.sub.2 purging or bubbling, is provided.