Can I put the editor in the Acknowledgements?
There is nothing wrong with acknowledging an editor that goes beyond what can be expected. It is of course not customary to provide such acknowledgement in most cases. Editors do not expect it and it may simply appear as inappropriate attempts at flattery. It is difficult to draw the line where acknowledgements are appropriate but, I have probably acknowledged editors in a couple of percent of my own papers. I have also been acknowledged a couple of times in my capacity as editor (out of editing hundreds of papers), all in cases where I have felt my assistance would save a paper that could otherwise be buried undeservedly. In any case, your description seems to fit a case where the acknowledgement is appropriate, although no editor would probably expect it.