Re: chem vs. chem engineering


"Bill Penrose" <penrose@xxxxxxx> wrote in message
news:1189466875.181182.101870@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On Sep 10, 2:57 pm, RichD <r_delaney2...@xxxxxxxxx> wrote:
What is the difference between chemistry and
chemical engineering?

The difference is bigger than it used to be. When I was in college in
the 1960s, chemEs had to take two intensive years of basic chemistry
before starting engineering courses.

Until 2004, I taught analytical chemistry to classes of resentful
ChemEs. They were only required to take first year intro chem and
analytical in the second year. In the analytical class, they carped
endlessly, 'Why do we have to know this ***?' I found out that they
were getting that attitude from their engineering professors.

It turns out that after a quick glance at kindergarten level
chemistry, ChemEs start learning computer programming, simulations,
and something called 'unit processes', which takes the place of
knowing boring stuff like the periodic table or reaction kinetics.

The modern curriculum assumes that its graduates have nothing in their
futures but the control rooms of refineries and chemical plants. In
fact, many inventors, research chemists, safety engineers, and even
military types I know started their careers as ChemEs.

Dangerous Bill



I'll add a little to what Bill said. A chemist is in charge of determining
which reactions will yield a particular product. A chemical engineer takes
that knowledge and scales it up to an industrial process, works out the unit
operations required, figures out how to control it, the economics,
thermodynamics, etc around it. They meet somewhere in the middle at the
chemical equations.

A chemist worries about the chemistry at the molecular level and may
consider a few milliliters a large reaction. A chemical engineer worries
about implementing the reactions reactions on a very large scale (sometimes
in the thousands of tons per day range). That includes reactant handling,
heating, cooling, mixing, and separating, and the required equipment all on
a much larger scale.

Put in a room together, a good chemist and a good chemical engineer will
have a great deal of mutual respect. They can understand one another quite
well, and they have some overlap, but neither can really do what the other
does well.

Michael


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