Aiming to Become Chemical Engineers for the Global Stage

We conduct research on phenomena involving gas-liquid chemical reactions, particularly those involving bubbles, covering everything from fundamental to applied aspects. We are also developing foundational technologies to produce fine particles through reactive crystallization, where crystals are precipitated by chemical reactions. This research is closely related to pressing global issues such as global warming, environmental pollution countermeasures, and energy resource problems, and its results are highly anticipated. Furthermore, we are developing high-performance, high-value-added chemical equipment that will pave the way for a new era. Allow us to introduce a part of our work.

Microbubbles, which are currently attracting worldwide attention, are tiny bubbles of 10–40 μm. They have several characteristics: a small bubble diameter, a slow rising velocity (long residence time in the liquid), high internal bubble pressure (a self-pressurization effect), and a negatively charged bubble surface. We are advancing research on the following themes, taking advantage of these characteristics of microbubbles.

Production of purified water through water quality purification

Development of high-performance bubble columns

Decomposition of organic substances in the liquid phase

Use of microbubbles mixed with ozone

for sterilization

Application to bioreactors

In other research utilizing bubbles, we are tackling:

The development of a bubble injection method

in a complete absorption treatment unit for organic chlorine compounds

using molten salt

The elucidation of the dissolution mechanism

of gas into liquid

in a vibrating agitator.

Additionally, with the aim of effectively utilizing dissolved resources in seawater and using carbon dioxide from factory exhaust gas, we are studying the mechanism of reactive crystallization (crystal precipitation by chemical reaction) for the production of magnesium, lithium, and calcium carbonates from seawater. We are also advancing research on the recovery of calcium phosphate from cheese whey (a byproduct of cheese production) through reactive crystallization, and on the reactive crystallization of nickel hydroxide particles, which are the raw material for the positive electrode of nickel-metal hydride batteries.

For those of you interested in the environmental problems and the effective use of marine resources that the 21st century demands we solve, please be sure to visit our website.

This is a photo from our lab retreat in Hakone. All members participated: 4 fourth-year undergraduate students, 4 first-year master's students, 4 second-year master's students, and 1 second-year doctoral student.

We are discussing experiments on microbubbles, a topic of current interest, with Lihan, a second-year student in the Doctoral Programs.

Master's students Kuze, Sakamoto, and Tamura of the reactive crystallization research group are examining the properties of particles obtained from their experiments on a computer screen.