Chemical engineering

Lore & Background

The term 'chemical engineering' has disputed origins. A 1996 article cites James F. Donnelly mentioning an 1839 reference to chemical engineering in relation to sulfuric acid production, but George E. Davis, an English consultant, is credited with coining the term. Davis attempted to found a Society of Chemical Engineering, but the Society of Chemical Industry was formed instead in 1881, with Davis as its first secretary. By 1910, the profession 'chemical engineer' was common in Britain and the United States.

In the 1940s, the limitations of unit operations alone became clear, leading to a focus on transport phenomena and process systems engineering. Developments before and after World War II were largely driven by the petrochemical industry, but advances also occurred in biochemical engineering, enabling mass production of antibiotics like penicillin and streptomycin, and in polymer science, paving the way for the 'age of plastics'.

Safety and environmental concerns grew after incidents such as the 1974 Flixborough disaster and the 1984 Bhopal disaster. In response, the IChemE required safety to be part of accredited degree courses after 1982. By the 1970s, legislation and monitoring agencies were instituted in various countries, and process safety emerged as a specific discipline.

Reader's Guide

Chemical engineering is significant for its role in transforming raw materials into essential products, from medicines and petrochemicals to plastics, on an industrial scale. Its principles underpin the design and operation of chemical plants, including safety and hazard assessments, process design, and control engineering. The field's evolution from unit operations to transport phenomena and process systems engineering reflects its adaptability to new challenges, such as the need for safer and more environmentally responsible manufacturing. The development of biochemical engineering enabled the mass production of antibiotics, while polymer science led to the age of plastics. Advances in computer science, including programs like Aspen HYSYS, have simplified plant design and calculations. The Human Genome Project also advanced chemical engineering by enabling large-scale DNA sequencing. Chemical engineers work in industry, research, and project management, applying their knowledge to minimize costs and maximize safety and profitability. Their work is guided by professional bodies like the IChemE and AIChE, and they typically hold degrees in chemical or process engineering.

Did You Know?

• The term 'chemical engineering' may have been used as early as 1839 in relation to sulfuric acid production, but George E. Davis is credited with coining it.
• The 1974 Flixborough disaster in the United Kingdom resulted in 28 deaths and damage to a chemical plant and three nearby villages.
• The Institution of Chemical Engineers (IChemE) required safety to be part of every accredited degree course after 1982.
• Programs such as Aspen HYSYS were developed to complete multiple chemical engineering calculations.

A Discipline That Bridges Every Scale

Chemical engineering occupies a unique position among the engineering fields because it refuses to stay within a single scale or a single science. At one end of the spectrum, a chemical engineer might be working with nanomaterials in a laboratory setting; at the other, the same principles govern enormous industrial facilities that transform raw materials, living cells, microorganisms, and energy into commercially useful products. The discipline draws simultaneously on chemistry, physics, mathematics, biology, and economics, weaving them into a coherent framework for designing, producing, transporting, and transforming materials and energy. The day-to-day responsibilities of a practicing chemical engineer span an impressively wide canvas: safety and hazard assessments, process design and analysis, computational modeling, control engineering, chemical reaction engineering, nuclear engineering, biological engineering, construction specification, and the drafting of operating instructions. This breadth means that the field is not merely about making a reaction work in a flask but about ensuring that the reaction can be scaled, controlled, made economical, and kept safe across an entire plant.

From Unit Operations to a Second Paradigm

For much of the twentieth century, the backbone of chemical engineering education in Britain and the United States was the study of unit operations—discrete physical steps like crystallization, filtration, drying, and evaporation that handle reactants, purify products, recycle unspent materials, and manage energy transfer. Yet by the 1940s it became evident that unit operations alone could not adequately address the design of chemical reactors. The field needed a deeper analytical language, and that language arrived in the form of transport phenomena, which offered a rigorous mathematical framework for understanding how mass, momentum, and energy move through a system. Alongside this analytical shift came process systems engineering, a synthetic discipline concerned with control systems and holistic process design. Together these ideas constituted what has been called a second paradigm. The petrochemical industry was the primary engine behind many of these advances before and after World War II, but the ripple effects reached far beyond oil and gas. In the 1940s, biochemical engineering breakthroughs enabled the mass production of antibiotics such as penicillin and streptomycin, and in the 1950s, progress in polymer science opened the door to what is often called the age of plastics.

Disasters That Redefined Safety

The mid-twentieth century brought a wave of industrial catastrophes that permanently altered how the profession thinks about risk. Rachel Carson's 1962 book Silent Spring warned the public about the toxic legacy of DDT and other persistent insecticides, shifting the conversation from purely economic efficiency to environmental stewardship. Then came the 1974 Flixborough disaster in the United Kingdom, in which a chemical plant explosion killed 28 people and devastated three nearby villages. The 1984 Bhopal disaster in India proved even more devastating, claiming at least 4,000 lives. These tragedies, among others, dealt a serious blow to the industry's public reputation and forced a reckoning. In response, the Institution of Chemical Engineers made safety a mandatory component of every degree course it accredited beginning in 1982. Governments in France, Germany, and the United States established legislation and monitoring agencies during the 1970s. Over time, the systematic application of safety principles to chemical and other process plants matured into its own recognized discipline, now known as process safety, ensuring that the lessons of those dark decades are embedded in every new design.

Digital Tools and the Genomic Frontier

The late twentieth and early twenty-first centuries have introduced tools and scientific frontiers that would have been unimaginable to earlier generations of chemical engineers. Advances in computer science transformed plant design and management: calculations and drawings that once consumed weeks of manual labor can now be completed in hours using specialized software such as Aspen HYSYS, which handles multiple chemical engineering computations in a single workflow. On the biological side, the completion of the Human Genome Project stands as a landmark that touched chemical engineering directly. Chemical engineering principles were applied to produce DNA sequences in large quantities, bridging the gap between genomics and industrial-scale manufacturing. Meanwhile, the profession's practical side continues to evolve. Chemical engineering design involves creating plans, specifications, and economic analyses for pilot plants, new facilities, or modifications to existing ones, all constrained by funding, government regulations, and safety standards. Project engineering—coordinating construction and managing large-scale investments—remains one of the largest employers of chemical engineers, and in the United States, ABET-accredited baccalaureate programs typically complement this with specialized training, electives, or graduate study.