The present invention relates to the extraction of lithium from liquid resources, such as natural and synthetic brines, leachate solutions from clays and minerals, and recycled products.

A diaryl carbonate containing a compound of the following formula (I) in an amount of less than 1,000 ppm by mass, and a method for producing the same:

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wherein R.sup.1 represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, or an aryloxy group.

A crystalline pigment or colorant composition having high color intensity and/or low sugar content, and methods and processes of preparation. The composition may comprise purified fruit and/or vegetable color juices.

We provide an evaporation based method for water recovery from gasification wastewater to achieve zero liquid discharge. Grey water from a gasification system is processed by an evaporation system which recovers >99% of the influent water and generates a solid phase in a crystallizing reactor. The crystallizing reactor converts dissolved solids present as highly soluble species into alternative chemical forms that are amenable to precipitation and removal from the liquid phase to achieve zero liquid discharge.

A levulinic acid composition A having: a. at least 95 wt. % of levulinic acid; b. between 5 wppm and 5000 wppm of formic acid; and c. less than 1000 wppm of angelica lactone, based on the total weight of the composition. A process for the isolation of a levulinic acid composition, having the following steps: a. performing acid catalyzed hydrolysis of a C6 carbohydrate-containing feedstock to obtain reaction product X, b. subjecting of reaction product X to solid-liquid separation to provide a composition 1, c. feeding composition 1 to at least two purification steps to treat composition 1 to obtain a levulinic acid composition, wherein a second or a further purification step is a melt crystallization step.

A processing unit for a liquid washing medium contaminated with sulphur oxides and/or nitrogen oxides, has an evaporation stage for concentrating the active components of the washing medium by an evaporator and/or by a heat exchanger, and has a collecting tank connected to the evaporator and/or to the heat exchanger. The collecting tank is configured as a crystallizer for removing sulfur oxides from the washing medium by crystallization of a sulphate, in particular of potassium sulphate. A separating device for carbon dioxide has a corresponding processing unit, and a method for processing a washing medium contaminated with sulphur oxides and/or nitrogen oxides uses a corresponding processing unit.

A stacked type falling film evaporator includes a first evaporator, a second evaporator, a first vapor recovering device, a second vapor recovering device and a vapor recompressor. The first evaporator and the second evaporator respectively have evaporation tubes of a length of 5 m to 10 m, and are stacked in such a manner that wastewater passes through the first evaporator and the second evaporator in order. The first vapor recovering device collects vapor generated from the wastewater in the first evaporator and supplies the collected vapor to the second evaporator. The second vapor recovering device collects vapor generated from the wastewater in the second evaporator and supplies the collected vapor to the first evaporator. The vapor recompressor compresses the vapor collected in the second vapor recovering device before the vapor is supplied to the first evaporator.

A resin containing a desirable compound is extracted from plant material and dissolved in a volatile non-polar solvent. The solvent is evaporated, cooling the solution and increasing the saturation level of the compound in the solution. A second volatile non-polar solvent, in which the compound is less soluble, is then added to the solution and evaporated. This again cools the solution and increases the saturation level until the compound has started to crystallize. The crystals are then filtered and rinsed. Crystallization is more rapid compared to traditional techniques. The resin is obtained from the plant material using an extraction solvent to form a solution, which is then floated above an immiscible liquid, where it is drawn off through a screen and the extraction solvent evaporated.

A process for treating wastewater or waste brines that include sodium and chloride ions. The waste brine is concentrated and thereafter directed to a Mirabilite crystallizer that produces hydrated sulfate salt crystals and a first solution. The hydrated crystals are melted to form an aqueous sulfate solution that is directed to a sodium sulfate crystallizer which produces sodium sulfate salt crystals. The first solution produced by the Mirabilite crystallizer is directed to a nanofiltration device which produces a permeate stream and a reject stream containing sulfate removed by the nanofiltration device. The permeate stream is directed to a sodium chloride crystallizer that produces sodium chloride salt crystals. The reject stream is recycled to the Mirabilite crystallizer.

A system and method for cleaning of a forced-circulation evaporative crystallizer. The crystallizer is used to produce salt solids and includes a circulation pump, a heat exchanger, a separator, and a vapor processor. Solids deposits accumulate during salt solids production within at least one of the circulation pump, heat exchanger, and separator. A solids deposits metric representative of an amount of the accumulated solids deposits is measured. The solids deposits metric is determined to deviate from a baseline by at least a cleaning threshold. Certain determinations are made based on the solids deposits metric: determining a cleaning mode and at least one of a type of cleaning solution and a duration for which at least one of the circulation pump, heat exchanger, and separator is to be cleaned. At least one of the circulation pump, heat exchanger, and separator is then cleaned in accordance with those determinations.