American Institute of Chemical Engineers - Organization for chemical engineering professionals. Website also offers information on chemical engineering processes & methods.
https://www.aiche.org/
Chem Consult - Is a non profit membership organization serving the chemical consulting needs of prospective clients.
https://chemconsult.org/
OCS Chemical Engineering - Chemical engineering service company providing water treatment chemicals and services for heating and cooling systems.
http://ocschemical.com/