A system and method for generating base water and precipitate, including combining produced water with seawater to precipitate barium sulfate from barium in the produced water and from sulfate in the seawater, and separating the precipitate to give the base water and the precipitate. The base water may have less than a specified amount of sulfate and be utilized for hydraulic fracturing fluid. The precipitate may give a weighting agent for drilling.

A method of removing barium and naturally occurring radioactive material from produced water. The method includes pretreating the produced water having a pH in a range of from about 4.0 to about 10.0 with a sulfate source to form a suspension of barium sulfate, radium sulfate, or a combination thereof, treating the pretreated produced water with an anionic flocculant and gravitational])′ separating the treated produced water from the barium sulfate, radium sulfate, or a combination thereof.

It is an object of the present disclosure to provide a method for inexpensively producing a high-performance barium sulfate powder which is obtained by using inexpensive barium sulfide as a raw material, has a high whiteness degree, and can suppress the generation of volatile components.

A method for producing a barium sulfate powder comprising a step of heat treating a raw barium sulfate powders obtained by using barium sulfide as a raw material at 600 to 1300° C., wherein a retention time X (minutes) at a heat treatment temperature of t ° C. is more than time expressed by the following general formula:

X (minutes)=A×10.sup.6×e.sup.(−0.015×t)

A is 8 or more, and an upper limit of X is 3000 minutes in the formula.

The present invention disclosed use of lactam as a solvent in the preparation of nanomaterials by precipitation method, sol-gel method or high temperature pyrolysis. These methods are able to recycle lactam solvent, which meet requirements of environmental protection.

The present invention relates to a process to produce high purity strontium sulfate and strontium carbonate from subterranean brines. The present disclosure also relates to chemical precipitations of subterranean brines to isolate strontium from divalent cations, such as calcium and barium. Such precipitations include the use of sulfate and subsequent solids separations and washing of the precipitate. In a latter step in the strontium carbonate process, a metathesis reaction with a carbonate is performed upon the strontium sulfate to produce strontium carbonate while allowing optional recycling of the sulfate. An additional rinse with acid or water of the strontium sulfate may be performed prior to metathesis to increase the purity of the resulting strontium carbonate.

A procedure of minimum environmental impact and maximum lithium recovery for obtaining concentrated brines with minimal impurity content from brines that embed natural salt flats and salt marshes. The procedure may include: building fractional crystallization ponds by solar evaporation; filling the ponds with natural brine; pre-concentrating natural brine to the maximum possible lithium concentration in the liquid phase without precipitating lithium-containing salts; cooling the pre-concentrated brine obtained in ensuring maximum precipitation of salts containing sulfate anion; chemically pre-treating the liquid phase of brine separated from precipitated salts by cooling to minimize sulfate anions in the liquid phase after cooling; pre-concentrating the pre-treated liquid phase to the maximum possible lithium concentration without precipitating lithium-containing salts; chemically treating the liquid phase of brine separated from precipitated salts to minimize the concentration of magnesium, calcium, boron and sulfate in the liquid phase; and concentrating the resulting liquid phase.

A system and method for generating base water and precipitate, including combining produced water with seawater to precipitate barium sulfate from barium in the produced water and from sulfate in the seawater, and separating the precipitate to give the base water and the precipitate. The base water may have less than a specified amount of sulfate and be utilized for hydraulic fracturing fluid. The precipitate may give a weighting agent for drilling.

The present invention relates to fine barium sulfate powder that can be readily and simply dispersed in resins or solvents; a resin composition, a coating composition, an ink composition, and a resin molded article each containing the barium sulfate powder; and a method for producing the barium sulfate powder. Provided is barium sulfate powder having a number average primary particle size of 1 to 100 nm, the powder including an organic compound on its surface, the powder in the form of compressed compact having a contact angle with distilled water of 10 to 170 degrees.

Processes for the recovery or purification of lithium species from various sources are described. Such sources include natural sources or deposits, such as in mining applications, and synthetic or non-natural sources, such as in the recycling of lithium species from batteries. In embodiments, the process comprises treating a Li.sub.2SO.sub.4-comprising aqueous solution with one or more barium salts to form a precipitate comprising barium sulfate (BaSO.sub.4). In embodiments, the processes may further comprise the preparation of a lithium sulfate-containing solution via treatment of the starting material or mixture with sulfuric acid. In embodiments, further treatments may be performed, for example prior to and/or subsequent to treatment with one or more barium salts, for example for initial or further sulfate removal, and/or removal of other metal species that may be present. The recovered lithium species be used directly, or converted into other forms, for use in a variety of applications.

The invention provides a low alpha dose barium sulfate particle having a silica content of 0.6% by weight or less, an average particle diameter of 1 μm or less, a sulfur content of 10 ppm or less, and an alpha dose of 0.07 cph/cm.sup.2 or less.