Abstract: A short presentation of chemical engineering evolution, as guided by its paradigms, is exposed. The first paradigm-unit operations-has emerged as a necessity of systematization due to the explosion of chemical industrial applications at the end of 19th century. The birth in the late 1950s of the second paradigm-transport phenomena-was the consequence of the need for a deep, scientific knowledge of the phenomena that explain what happens inside of unit operations. In the second part of 20th century, the importance of chemical product properties and qualities has become essentially in themarket fights. Accordingly, it was requiredwith additional and even new fundamental approaches, and product engineering was recognized as the third paradigm. Nowadays chemical industry, as a huge materials and energy consumer, and with a strong ecological impact, couldn't remain outside of sustainability requirements. The basics of the fourth paradigm-sustainable chemical engineering-are now formulated.

Key words: Paradigms, Unit operations, Transport phenomena, Product engineering, Sustainable chemical engineering

摘要： A short presentation of chemical engineering evolution, as guided by its paradigms, is exposed. The first paradigm-unit operations-has emerged as a necessity of systematization due to the explosion of chemical industrial applications at the end of 19th century. The birth in the late 1950s of the second paradigm-transport phenomena-was the consequence of the need for a deep, scientific knowledge of the phenomena that explain what happens inside of unit operations. In the second part of 20th century, the importance of chemical product properties and qualities has become essentially in themarket fights. Accordingly, it was requiredwith additional and even new fundamental approaches, and product engineering was recognized as the third paradigm. Nowadays chemical industry, as a huge materials and energy consumer, and with a strong ecological impact, couldn't remain outside of sustainability requirements. The basics of the fourth paradigm-sustainable chemical engineering-are now formulated.

关键词: Paradigms, Unit operations, Transport phenomena, Product engineering, Sustainable chemical engineering