Tuesday, September 29, 2009

Chemist or chemical engineer

I am often asked what is the difference between a chemist and a chemical engineering. Many of my friends, who are not in academics, think it is the same. In my native town, where I have several friends, all of them introduce me a chemistry lecturer, who teaches only 3 hours a week and always wonder what I do for the rest of the time (the answer is write blogs). Anyway, there is an interesting discussion on the differences between a chemist and chemical engineering. Here is what one of the authors, Rich Lemert, wrote,

The two biggest differences between chemists and chemical engineers, however, are 1) chemical engineers are much more quantitative, whereas chemists are more qualitative; and 2) chemical engineers have an economic understanding that chemists usually lack.

1) While chemistry (along with physics) is more quantitative than many other sciences, there are still large areas within the field where you don't really need much more math than some high-level algebra. Organic chemistry, for example, is more concerned with understanding reaction mechanisms and can often care less about the details of how fast the reaction takes place. Chemical engineers don't worry so much about how a chemical forms, though, put are very concerned with how fast it forms, how much heat is evolved/consumed in the reaction, and yield.

2) A chemist's economic concerns pretty much start and end with "how much will it cost to do this experiment". Chemical engineers are trained to go much further. To give an example, let's say a company has two potential products in development, both of which will require the building of a new plant to produce. Product A is more expensive to produce, but the process is not too challenging and a plant could be on-line in less than a year. Product B offers a higher profit margin, but it requires the use of some exotic equipment that require two years lead time to purchase. The company cannot afford to build both plants, so it must decide which one to build. The engineer knows how to make that decision.

My tryst with chemistry was only after I joined IISc. I was fascinated by the materials synthesized by my colleagues in solid state chemistry unit (SSCU), whose building is opposite to the chemical engineering. Encouraged by the colleagues in this department, my students and I worked on using these materials as catalysts for various reactions. This has resulted in several joint students and publications and I have been most benefited by this association, which has finally resulted in me becoming an associate faculty in SSCU. Of course, CNR Rao, who founded SSCU, has been an inspiration and I was extremely delighted when he congratulated me on the Bhatnagar award mentioning that he got the award the same year I was born !


Anonymous said...

since you are talking of diff between chemistry and Chem engg thought what are your views on science education in India being by and large divorced from engg & technology. there are exceptions like IIT & IISc but by large there seems to be a disconnect.

Anonymous said...

A slightly different note:

How is the medieval subject of "alchemy" related to either? I have had some chemists angrily tell me that "alchemy is witchcraft and we don't like to call it an ancestor-field". Some others smile when alchemy is mentioned and refer to it fondly like they are talking about a "great grandfather that went senile".

In my field of Electrical Engineering, people are very fussy about our history and everyone takes pride in the accomplishments of Volta, Faraday and Gauss, although, we are a relatively "new kid on the block" :-)

Are Chemists and Chemical Engineers equally fussy about their history?

Giri@iisc said...

Except for me, there is no collaboration between chemical engineering and chemistry. Similarly, collaboration is minimal between sciences and engineering even in IIT/IISc. However, the director has instituted some interdisciplinary areas and the collaboration is now increasing. Still it is less than 10%.

Anonymous said...

since many univs abroad have started dedicated phd programs in chemical physics separate from physics and chemistry, where does chemical physics fall in this differentiation between chemistry and chemical engineering ?

Anonymous said...

Just today I heard, during a seminar, an illustration of this difference. A PhD student (btw, he is Indian) was presenting his research on a design of a new plant. Asked if the catalyst was in a powder form, he answered: "I don't know anything about this (the chemical part)".


Anonymous said...

Well, I think some branches of study within chemistry like physical chemistry, quantum chemistry and computational chemistry is more quantitative than chemical engineering. Chemical engineers (at least in industrial practice) like other engineers are experts at developing and optimizing high throughput systems than the scientific discipline of chemistry.
The science behind this scale up requires deeper understanding of mass transfer and hydrodynamics; this disciplines are emphasized in chemical engineering but not as much in chemistry.

Viswa said...

Dear Sir,

It was amusing to read the article. However I beg to differ. Let me elaborate... Let me cite a classical example of the manufacture a pharmaceutical molecule. The organic chemist in the industry is the one who decides on the steps and the "economics", safety and feasibility of the product. Then the quality control and analytical development lab(read analytical chemist) says that this is a feasible and "economical" method of testing and is safe for consumption as per international guidelines. Then the synthetic and analytical chemist hands it over for scaleup at kilo and tonne scale thro a process called tech transfer wherein the process is handed over to the production team (read chem enggrs). It is at this step that enggrs see the reaction think about optimisation and cost cutting.... They too try their part to reduce cost. But the part in the article depicting chemists to be ignorant of the cost considerations is really funny and foolish to comment since every person whether the chemist or the engineer has his own role to play.

And in this regard the chemists have a larger say in cost reduction :)