In this blog post, we’ll examine the fundamental differences between chemistry and chemical engineering and explore the roles and purposes each discipline serves in science and industry.
What is Chemical Engineering? And how do Chemistry and Chemical Engineering differ? As modern science has advanced and the range of academic disciplines has diversified, chemical engineering has emerged as a distinct branch of chemistry. However, most people still fail to distinguish between the two and tend to think, “Aren’t they both just about studying chemistry?” Yet, not only do the two disciplines cover different subject matter, but their respective objectives are also distinctly different.
Chemistry is a branch of the natural sciences that investigates and understands the substances and various phenomena found in nature. Its primary goal is to research and discover answers to questions such as, “What kind of substance is this, and what are its properties?” and “What causes this phenomenon to occur?” In other words, chemistry is a natural science that pursues the truth of knowledge, standing shoulder-to-shoulder with mathematics, physics, biology, and earth science.
On the other hand, chemical engineering is a branch of engineering that focuses on production and economic efficiency. It primarily investigates questions such as “How can this be produced on a large scale?” and “How can this be produced more cheaply and efficiently?” In other words, chemical engineering is a discipline that creates processes that did not previously exist, ultimately aiming to generate significant profits. For example, if a chemist discovers a substance called “A” and its properties, a chemical engineer investigates whether substance “A” is useful to humans and how it can be mass-produced. In summary, chemistry can be described as the discipline that answers the “what” and “why” questions regarding what has not yet been discovered, while chemical engineering is the discipline that creates something from nothing and seeks answers to the “how” questions.
The crown jewel of chemical engineering is the chemical process. A process refers to the entire sequence of steps involved in transforming relatively low-value raw materials into higher-value products through reactions, separation, and purification using equipment such as reactors and separators. The types of such processes are extremely diverse, ranging from those with low added value but capable of mass production—such as crude oil separation and processing, fertilizer production, and food processing—to those with relatively low production volumes but which produce high-value-added materials relative to their raw materials, such as pharmaceutical manufacturing, semiconductor processes, and polymer synthesis.
When these processes come together, they form a plant, which is also commonly referred to these days as an industrial park. The process of establishing a factory can be broadly divided into three categories: turnkey systems, license purchases, and custom manufacturing based on research institute requests.
A “turnkey system,” as the name implies, is a system where the factory can be put into operation immediately—simply by “turning the key.” In other words, it is a system in which all the necessary equipment, facilities, personnel, and other supplies are purchased in their entirety from overseas to begin production. The advantage of this system is that it can be implemented even without any technical expertise required to establish a factory, and since there is no responsibility for the factory itself, any errors that occur can be resolved at no cost. However, this system has the disadvantage of requiring enormous costs and royalty payments to establish the factory, and it does not grant ownership rights to the facility. The Chungju Fertilizer Plant in the 1950s and 1960s serves as a good example. At that time, South Korea was an agricultural nation, so the demand for fertilizer was very high. However, since South Korea lacked the technological capability to produce fertilizer, it had no choice but to receive a complete fertilizer production plant as foreign aid and produce fertilizer that way. Thus, the turnkey system is a method of building a plant when there is virtually no technological capability.
Next is the license purchase method. This involves purchasing only the core processes necessary for building the plant and constructing the rest independently. Currently, most of South Korea’s chemical plants are built using this method. When a country possesses some technical capability but lacks the technology for the core process, it pays only for that specific core technology. This approach also has the drawback of incurring high costs and royalty fees for the purchased core process.
Finally, there is the method of commissioning domestic research institutes to develop the technology. In other words, this involves providing research funding to national or university research institutes to develop the technology needed for the plant, thereby enabling independent production without reliance on foreign sources. While this approach has the advantage of eliminating dependence on foreign countries and fostering the development of domestic technological capabilities, it also has the drawbacks of uncertainty regarding technology development and the time-consuming nature of the process. Since South Korea’s technological capabilities are still insufficient and the patents for all publicly available processes are held overseas, there are almost no plants built using this method. However, if we abandon this approach and simply purchase technology from abroad, we will ultimately become technologically dependent on various foreign countries, which will hinder national development; therefore, we must not abandon this approach.
Chemical engineering is becoming increasingly important across various industrial sectors. With the recent rise in concern over environmental issues, chemical engineering is playing a crucial role in providing solutions for sustainable development. For example, various technologies related to environmental protection—such as the development of eco-friendly energy sources, waste treatment technologies, and water treatment processes—are emerging as research topics in chemical engineering. Furthermore, the field of biochemical engineering is contributing to the development of cutting-edge products—such as pharmaceuticals, biofuels, and biomaterials—through the convergence of biotechnology and chemical engineering.
In conclusion, chemistry and chemical engineering exhibit clear differences in their respective objectives and fields of research. While chemistry is the discipline that explores the principles of natural phenomena and the nature of matter, chemical engineering is the discipline that develops technologies and processes applicable to real-world industries based on this knowledge. The two disciplines are complementary and play an essential role in the development of modern society. Understanding the differences between these two disciplines and recognizing their respective importance will greatly contribute to the advancement of science and technology, as well as to improving our quality of life.
