Twelve hours is a very long time for a dog to be alone. There are probably some odd animals out there who would be able to handle such social isolation, but they would not be common and you would not be likely to find one of them.
If you really want a dog, you need to make some adjustments. Any of the breeds on this list would be okay but only if you have somone coming in during the day to walk and socialize your dog, consider a doggy daycare, and you have at least two dogs so that the first does not get so lonely.
As I suggest, the best thing you can do is to find an adult dog. Visit your local animal shelter and tell them of your need, and tell them what kind of dog you are looking for. It is possible they will turn you down because of the long time away from home. It is also possible that they will suggest another dog type that does not get along as well because they have too many available.
If turned down by the shelter, despite the suggestion of a dog walker and doggy daycare, you should also contact a breed rescue. Type in the breed, your area, and the word "rescue" into your search engine. You may not have a rescue in your area but you can call the one closest to you.