At present, rapid population growth, global warming, indiscriminate drain of industrial wastewater and oil spill incur dwindling resources of available fresh water, devastatingly affecting our living environment. Hence, oil/water separation has attracted considerable attention due to the serious water pollution caused by oil spill accidents and oily wastewater from industries, etc. This has led to active researches for the improvement of oil/water separation efficiency.

Superhydrophilic-superoleophobic membranes are not fouled by oil, which means high separation efficiency and long lifetime. Hence, they are a main target for the fabrication of oil/water separation membranes.

There are many superhydrophilic-superoleophobic materials available such as fabrics, metal meshes and polymer filtration membranes. Since they are usually hydrophobic, their wettability characteristics should be improved to be superhydrophilic-superoleophobic. Dopamine has attracted much attention recently due to its potent adhesion property. Based on the strong adhesion behaviour and the intrinsic capacity for facile secondary treatments, a great number of approaches have been put forward for surface modification of solid materials.

Kim Myong Hak, a researcher at the Faculty of Chemical Engineering, has proposed a novel method to improve the hydrophilicity of stainless steel mesh by coating a polydopamine (PDA) as a transition layer on the surface of a hydrophobic stainless steel mesh and modifying a hydrophilic triblock copolymer onto the surface.

The water contact angle on the triblock copolymer-modified mesh in the air is 0°, which proves the mesh to be superhydrophilic. The oil (dichloromethane) contact angle on the surface of the modified mesh in water is 155°, exhibiting greater underwater superoleophobicity than on the surface of mesh with only a polydopamine layer.

The triblock copolymer/polydopamine modified mesh could selectively separate oil from immiscible oil/water mixtures with high separation efficiency of above 96%.

This is an era of Industry 4.0. The IoT is the core technology of Industry 4.0, which tags information such as the shape, position, property and history of all things including human beings and manages them in real time by connecting them with the Internet. Being tagged and connected with the Internet by the Radio Frequency Identification Device (RFID), all things are in real-time Smart management.

If the spindle unit which is the core unit of a machine tool is in real-time management through the Internet by introducing Internet of Things (IoT) from the design stage, the quality of design can be further improved and put on a scientific basis.

Kim Son Ho, a researcher at the Faculty of Mechanical Science and Technology, defined the tag content of machine parts, tagged spindle unit parts of "RT-350" CNC lathe and introduced a 3D modeling algorithm for them. In addition, he programmatically implemented an RFID by identifying the shape, position, property and history information of the parts using the IF-THEN-module of rule-based reasoning (RBR) of the expert system.

As a result, the design quality of a spindle unit has further increased and the time for design has been reduced by 1/5. In addition, the design has become more intelligent.

Methanol is an important basic raw material for the chemical industry and it has many applications in organic synthesis, dyes, medicines, pesticides, etc. Methanol, which is chemically mass-produced from coal gasification and natural gas, is a feed ingredient of C1 chemical industry and organic chemical industry.

Low-pressure methanol synthesis using copper-based catalysts is widely used worldwide in the production of methanol by coal gasification. Since the methanol obtained from this process contains water and a mixture of various organic substances, it must be purified for the usage as a raw material for the organic synthesis industry. Distillation is the most matured separation process, which is widely used for the purification of methanol.

Ro Jin Hyok, a researcher at the Faculty of Chemical Engineering, has simulated a methanol distillation process for obtaining high-purity methanol from crude methanol produced from coal gasification, and investigated the influence of some factors on its purity.

The factors include the rate of extracted water in the pre-distillation column, and the reflux ratio, the amount of distillate and the temperature of feed in the main distillation column.

The results show that the optimum conditions for the process operation are as follows. The rate of extracted water in the pre-distillation column is 3 500kg/h and the reflux ratio, the rate of distillate and the feed temperature are 1.1, 17 000kg/h and 69℃, respectively, in the main distillation column.

Under these conditions, the purity of methanol is 99.93% and the recovery rate is over 98.9%.