The global demand for raw lithium materials is rapidly increasing, accompanied by the demand for lithiumion batteries for next-generation mobility. The batch-type method, which selectively separates and concentrates lithium from seawater rich in reserves, could be an alternative to mining, which is limited owing to low extraction rates. Therefore, research on selectively separating and concentrating lithium using an electrodialysis technique, which is reported to have a recovery rate 100 times faster than the conventional methods, is actively being conducted. In this study, a lithium ion selective membrane is prepared using lithium lanthanum titanate, an oxide-based solid electrolyte material, to extract lithium from seawater, and a large-area membrane manufacturing process is conducted to extract a large amount of lithium per unit time. Through the developed manufacturing process, a large-area membrane with a diameter of approximately 20 mm and relative density of 96% or more is manufactured. The lithium extraction behavior from seawater is predicted by measuring the ionic conductivity of the membrane through electrochemical analysis.

분자체(molecular sieve)로 알려진 제올라이트 분리막 중에 8-membered ring(8 MR) 구조를 지닌 제올라이트를 다공성 지지층 위에 연속적인 분리막 형태로 제작하고자 한다. 8 MR 구조 중에서도 소수성을 띠는 제올라이트 기반으로 높은 이산화탄소 선택적인 분리 능력을 보이고자 한다. 특히, 이산화탄소를 분자 크기가 큰 질소나 메탄으로부터 분리하는 게 아니라, 도전적인 과제로서 수분이 존재하는 feed 조건에서 높은 이산화탄소 분리 능력을 지닐 수 있도록 분리막을 제작하고자 한다. 이번 발표에서는 최근에 얻은 제올라이트 분리막을 만드는 방법과 그 방법으로 제작한 제올라이트 분리막의 이산화탄소 분리능력에 대해 발표하고자 한다.

A ZIF-8 membrane was prepared via counter diffusion method. To control the diffusion rate, two supports with different pore structure were employed, conventional and modified α-Al2O3 disc; disc A and disc B. The ZIF-8 membranes are derived their name from the supports; ZIF-8-A and ZIF-8-B. While ZIF-8-A was grown at the surface of the disc A, ZIF-8-B was grown inside the disc B. At 200°C, ZIF-8-A and -B exhibited H2/CO2 separation factor (SF) of 6.69 and 8.21. In long-term thermal stability tests, both ZIF-8-A and -B were withstood their properties at 200 and 250°C for 72 h. At 300°C, SF of ZIF-8-A fell after ~2 h, however, that of ZIF-8-B dropped after ~10 h. To sum up these features, ZIF-8-B showed higher H2 selectivity and thermal stability than ZIF-8-A, since ZIF-8 membrane was synthesized inside of the support.

Sulfur copolymer (poly(S-r-CEA)) was synthesized via facile inverse vulcanization of elemental sulfur with 2-carboxyethyl acrylate (CEA). Polysulfide (PS) oligomer was soluble to common solvents including DMF, producing homogenous dope solution with PAN as filler. PS-PAN was electrospun resulting to nanofiber membrane effective for Hg2+ sequestration with recorded maximum capacity of 612 mg g-1 based on Langmuir model isotherm. Kinetics, selectivity and reusability were also evaluated. This work presents new and cheap yet effective material for heavy metal sequestration from contaminated water. This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (2015R1A2A1A15055407) and by the Ministry of Education (No. 2009-0093816).

There have been continuous research activities towards the designing of various separation technologies for the sequestration of CO2. Organic polymer membranes pay a great attention for its eco-friendliness, simple operation and energy-saving. Polymer membranes such as polyimides, polyethers, TRs and PIMs are well known for their high permeability and excellent mechanical, chemical, and thermal properties. However, the foremost challenge for these polymeric membrane materials is their enhanced selectivity to CO2 without sacrificing permeability. The selectivity problems would be overcome by ionic liquids (ILs), which lead to a considerable attention on RTILs-based sequestrations for CO2/N2 and CO2/CH4 separations. The current research trends based on RTIL polymer membranes, together with our original concept of applying RTIL to various polymeric structures will be presented.

This study was conducted to develop the domestic production of a controlled atmosphere (CA) storage system, including nitrogen generator and carbon dioxide eliminator using selective gas separation membrane and operating program. Generally, the gas composition inside general cold stores constantly changes due to the metabolic activity of the respiring vegetables and fruits and leakage of gases through doors and walls. However, the CA container developed by our research team is able to control of the level of oxygen and carbon dioxide inside the reefer, making it simple and effective in operation. The efficiency of the nitrogen generator to replace oxygen with nitrogen inside the CA container was approximately 1.33% per hour. The change in oxygen concentration inside the CA container during the operation refrigerator almost did not show any difference for 8 days. Therefore, CA storage container should be a promising approach to maintaining the high quality of agricultural products during storage.

본 연구는 nPr-BTP/nitrobenzene 추출 계에 의한 악티나이드(III)의 선택적 분리로, 우선 자연친화적 CHN 형 의 nPr-BTP (2.6-Bis-(5.6-n-propyl-1.2.4-triazin-3-yl)-pyridine)를 합성하고, 이의 희석제에 대한 용해성 및 질산에 대한 안정성 등을 평가하였다. 악티나이드(III)의 대표원소로는 Am을 선정하였으며, 0.1M nPr-BTP/nitrobenzene-1M , O/A=2의 조건에서 Am은 약 85%, RE 원소는 Eu가 8%, 기타 Nd, Ce, Y 등은 3% 이하가 추출되어 (이때 Am/Eu의 상호분리 계수 약 60정도) 악티나이드(III)의 선택적 추출에는 별 문제가 없을 것으로 판단되었다. 그러나 Am의 역추출의 경우 0.05M 질산용액으로 O/A=1 에서 약43%가 역추출 되었으며, O/A=0.3에서도 65% 정도만이 역추출 되어 질산 이외의 다른 역추출제의 개발이 요구되고 있다.

초음파 해쇄, 침강 분리 및 원심 분리 등의 물리적 처리 기술을 적용하여 감포 13호 및 35호 광구의 벤토나이트 원광석으로부터 몬모릴로나이트를 선택적으로 회수할 수 있는 습식 고순도화 공정 특성을 연구 개발하였다. 초음파를 이용한 해쇄는 슬러리의 농도가 7 wt.%인 경우 우수한 해쇄 결과를 나타냈으며 감포 13호의 경우는 30분, 감포 35호의 경우는 10분 이내에 대부분의 해쇄가 종료되었다. 30분간 침강 분리를 행한 결과 감포 13호은 원광의 약 52 wt.%, 감포 35호는 약 64wt.%를 정제된 산물로 회수하였으며, CEC는 각각 119.4, 124.5 meq/100 g이었다. 원심 분리를 이용한 입자 분리 결과, 원심 분리기의 회전수 1,000 rpm 이내에서 석영, 장석 등 대부분의 불순 광물들이 분리 제거되었다.