Sk Innovation Co., Ltd.

Sk Global Chemical Co., Ltd.

Min Ji Sung

Ji Min Kim

Sung Real Son

Jung Yul Son

Hyeon Bae Ha

Sang Uk Kim

Yeon Hwa La

Seung Ok Lee

Suk Joon Hong

Young Bin Seo

In Ae Lee

Woong Chul Shin

Choon Hwan Song

In a method for recovering an active metal of a lithium secondary battery, a cathode active material mixture is prepared from a cathode of a lithium secondary battery. A first reductive process using a first reductive reaction gas and a second reductive process using a second reductive reaction gas that has a higher reaction source concentration than that of the first reductive reaction gas are performed sequentially and continuously to convert the cathode active material mixture into a preliminary precursor mixture. A lithium precursor is recovered from the preliminary precursor mixture. A lithium recovery ratio may be increased by a stepwise reduction while preventing an increase of heating value.

Method for recovering active metal of lithium secondary battery

A method for isolating a lithium precursor according to an embodiment of the present disclosure includes preparing a preliminary precursor mixture including a preliminary lithium precursor and a preliminary transition metal precursor, mixing the preliminary precursor mixture and a precipitation liquid in a reactor to form a precursor mixture, and injecting a non-reactive gas into the precursor mixture. Accordingly, the lithium precursor can be isolated with high yield and high efficiency.

Method for isolating lithium precursor and system for isolating lithium precursor

In a method for recovering active metals of a lithium secondary battery according to an embodiment, a cathode active material mixture is collected from the cathode of the lithium secondary battery, the cathode active material mixture is reduced by a reducing reaction to prepare a preliminary precursor mixture, an aqueous lithium precursor solution is formed from the preliminary precursor mixture, and an aluminum-containing material is removed from the aqueous lithium precursor solution with an aluminum removing resin.

A method of producing carbon nanotubes in a fluidized bed reactor includes preparing a carbon nanotube by supplying a catalyst and a carbon source to an interior of the fluidized bed reactor having an internal pressure of 0.5 barg to 1.2 barg (gauge pressure), thereby improving the yield and purity of carbon nanotubes.

Method of producing carbon nanotubes in fluidized bed reactor

Provided is a method of producing carbon nanotubes by supplying a catalyst and a carbon source to a fluidized bed reactor. The fluidized bed reactor has an expanded zone. A flow velocity (linear velocity) of a raw material supplied to the fluidized bed reactor is equal to or higher than a terminal velocity of an internal material in the fluidized bed reactor.

Disclosed is a method of purifying carbon nanotubes, including treating carbon nanotubes with an inert gas at a high temperature in a low vacuum in a reactor and obtaining ultrapure carbon nanotubes, wherein the ultrapure carbon nanotubes contain 50 ppm or less of each metal remaining therein.

Growing community of inventors

Daejeon, South Korea

Min Ji Sung