Folder on left side of the dock
Yes, this is possible, but it may not behave the way you want. 

What I mean is that adding a folder to the right-hand side of the Dock allows it to spring open, and also provides you with options as to how its contents should be viewed and sorted. Placing it on the left-hand side does nothing except open the folder for you within the Finder. If this is acceptable, then follow these steps:


Wthin the Finder, select your folder and press commandI (or go to File > Get Info)
In the Get Info window that pops up, you’ll see a Name &amp; Extension field. Add .app to the end of the folder name.
Press return and in the pop-up window that appears, click on the Add button
You’ll notice that the folder icon has changed - ignore this for now and leave the Get Info window open
Now add the folder to the location you want
Now go back to the Get Info window and remove the .app you added to the folder name at Step 2
Press return and in the pop-up window that appears, click on the Remove button
You can now close the Get Info window


In a few moments the folder’s icon should return to normal and you can now click on it within the Dock. Remember, doing so will only open the folder in the Finder.

Note: If you ever accidentally remove the folder from the Dock you will need to repeat the 8 steps above. However, you may find you need to restart your Mac before doing so.