Re: PhD (Chemical engg) in Switzerland
ETH Zurich and EPFL Lausanne would both have it, not sure what Chemical Engineering tranfers into for the swiss system though. Better to search for the proper research group (eg. Polymer Structures) rather than broad subject (Chem Eng) - for example the computational mineral physics group is not in the computer science, earth science or physics department, but material science....Both 'Technical Universities' will have a list of all Institutes on their website, start there.
Also remember that just because your undergrad is in one field a lot of people change departments for their PhD although they still work in the same field, like when a Chemist BSc deos a PhD in medicine or protein structure (physics department)
Not sure what of the non-ETH/EPFL domain schools would have a program.
As is general everywhere with PhD positions, don't approach the university, but find a potential supervisor (you should have a reasonable idea of the type of work you want to do) and contact him/her with your interests and if there is an open position in their group for something similar...