If you don't have very good ventilation/fume hood you may want to reconsider performing this reaction. I believe that this will produce the extremely carcinogenic bis(chloromethyl) ether. I believe that someone here recently posted some variations on this procedure that are supposed to reduce the bis(chloromethyl) ether production.
Edit:
Here we are: thread beginning with Post 250931 (https://www.thevespiary.org/talk/index.php?topic=12061.msg25093100#msg25093100)
(Antoncho: "A safe an easy way to chloromethylate.", Novel Discourse)
5 moles of HCl gas means about 500ml muriatic acid. Not too bad if you ask me. And the H2SO4 can either be boiled to concentrate it for reuse or it can be used for neutralisation, A/B etc.
https://www.thevespiary.org/rhodium/Rhodium/chemistry/hclgas.argox.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/hclgas.argox.html)
Post 253440 (https://www.thevespiary.org/talk/index.php?topic=11355.msg25344000#msg25344000)
(ChemicalSolution: "Easy(er?) chloromethylation", Novel Discourse)
SWIM posted this a while ago for review.. Not much was said. This seems 10x easier than the HCl method... But she wanted to try both of them to compare.
In the HCl method, what would the molar ratio of benzene:ZnCl2 be?
Julia