I need help as to how can I send a professional follow-up email to a company (petroleum company) after requesting data from them a month ago. The data is in relation to natural gas volumes etc. The company has no obligation to send it however it's being requested by a university and I would like to know if they got the email since we got not reply and if any further assistance can be rendered.
Call the customer services number for the company in question and talk to somebody. Be friendly and approachable and hope that you're speaking with someone helpful. If they're not helpful, call again on a different day with the hope of speaking to someone else.
Describe who you are and the purpose of this request and ask what would be the best email address/phone number to use.
If you simply emailed the "contact" email address, it's likely that your email is in a large pit with many other spam and random emails, never to be read.
What you're trying to do here is target the person/department who can answer these questions directly. It's a good skill to develop.
You don't specify in your question whether this was an enquiry sent to particular person or whether it was sent to a generic account.
If you sent it to a named contact then you could follow-up with that person directly, calling them up would probably be best since it seems that e-mail hasn't gotten their attention.
If this was a "cold" request (i.e. there was no prior relationship with the contact) then it's entirely possible that they ignored the e-mail entirely, especially if the request involved sending any data the company doesn't typically make public or if it required any significant time/effort investment to complete. I would suggest contacting the main customer contact number for the company and enquiring as to whether a) your request is something they could accomodate and b) who the right person would be to contact regarding it.
If it was sent to a generic contact e-mail then chances are that exactly as Snow states in his answer it has never been seen, or has been seen and discarded. Generic mailboxes are rarely monitored in much detail (the spam levels are simply too high) and it is often a fairly low level employee who is tasked with looking for specific sorts of inquiries and forwarding them up the chain. It's not unexpected that anything outside of what they have been tasked to watch for will simply be discarded out of hand amongst the 'noise'.