An alumina-based adsorbent and method of making exhibiting high affinity and capacity towards cations and oxyanions in a broad pH range and presence of large excess of competitive ions. Alumina based adsorbent is a mixed oxide of alumina existing in tetra-, penta-, and octahedral coordination at specific ratio, and oxides of polyvalent metals of elements titanium, zirconium, tin, cerium, lanthanum, iron, or combinations thereof. The alumina-based adsorbent may be used for selective removal of oxyanions of fluoride, phosphorus, arsenic, chromium, and/or selenium, and/or cations of lead, mercury, cadmium, copper, and/or zinc, from drinking water, industrial streams and wastes, in medicine and food industry.

An alumina-based adsorbent and method of making exhibiting high affinity and capacity towards cations and oxyanions in a broad pH range and presence of large excess of competitive ions. Alumina based adsorbent is a mixed oxide of alumina existing in tetra-, penta-, and octahedral coordination at specific ratio, and oxides of polyvalent metals of elements titanium, zirconium, tin, cerium, lanthanum, iron, or combinations thereof. The alumina-based adsorbent may be used for selective removal of oxyanions of fluoride, phosphorus, arsenic, chromium, and/or selenium, and/or cations of lead, mercury, cadmium, copper, and/or zinc, from drinking water, industrial streams and wastes, in medicine and food industry.

Zinc oxide-based sorbents, and processes for preparing and using them are provided, wherein the sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents contain an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two-phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl.sub.2O.sub.4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 50 nm (500 Angstroms). Preferably the sorbents are prepared by using an alkali metal base to convert a precursor mixture, containing a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component, with the resulting sorbent having a sodium level within a desired range.

Zinc oxide-based sorbents, and processes for preparing and using them are provided, wherein the sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents contain an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two-phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl.sub.2O.sub.4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 50 nm (500 Angstroms). Preferably the sorbents are prepared by using an alkali metal base to convert a precursor mixture, containing a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component, with the resulting sorbent having a sodium level within a desired range.

A system and method of pre-purification of a feed gas stream is provided that is particularly suitable for pre-purification of a feed air stream in cryogenic air separation unit. The disclosed pre-purification systems and methods are configured to remove substantially all of the hydrogen, carbon monoxide, water, and carbon dioxide impurities from a feed air stream and is particularly suitable for use in a high purity or ultra-high purity nitrogen plant. The pre-purification systems and methods preferably employ two or more separate layers of hopcalite catalyst with the successive layers of the hopcalite separated by a zeolite adsorbent layer that removes water and carbon dioxide produced in the hopcalite layers.

A system and method of pre-purification of a feed gas stream is provided that is particularly suitable for pre-purification of a feed air stream in cryogenic air separation unit. The disclosed pre-purification systems and methods are configured to remove substantially all of the hydrogen, carbon monoxide, water, and carbon dioxide impurities from a feed air stream and is particularly suitable for use in a high purity or ultra-high purity nitrogen plant. The pre-purification systems and methods preferably employ two or more separate layers of hopcalite catalyst with the successive layers of the hopcalite separated by a zeolite adsorbent layer that removes water and carbon dioxide produced in the hopcalite layers.

Provided are a method of purifying an alpha-olefin and a composition for purifying an alpha-olefin therefor. More specifically, a method of purifying an alpha-olefin having an excellent effect of removing impurities in the alpha-olefin and a composition for purifying an alpha-olefin therefor are provided.

A system, apparatus and methods are described for extracting carbon dioxide from air. The system may receive air blown over a contactor. The contactor can be coupled to a cooling tower. The contactor may comprise sorbent material to absorb carbon dioxide from the blown air. The sorbent material may be transported and placed into a regeneration reactor. The carbon dioxide in the sorbent material may be extracted via the regeneration reactor. The extracted carbon dioxide may be pressurized into and stored in a pressurized container.

A system, apparatus and methods are described for extracting carbon dioxide from air. The system may receive air blown over a contactor. The contactor can be coupled to a cooling tower. The contactor may comprise sorbent material to absorb carbon dioxide from the blown air. The sorbent material may be transported and placed into a regeneration reactor. The carbon dioxide in the sorbent material may be extracted via the regeneration reactor. The extracted carbon dioxide may be pressurized into and stored in a pressurized container.

This invention relates to a method for the preparation of lithium carbonate from lithium chloride containing brines. The method can include a silica removal step, capturing lithium chloride, recovering lithium chloride, supplying lithium chloride to an electrochemical cell and producing lithium hydroxide, contacting the lithium hydroxide with carbon dioxide to produce lithium carbonate.