With the specs you are showing here it should take no longer than an hour, and probably significantly less. Plan for 2 hours is my suggestion, then if you have plenty of time left over, you’re good. Better to plan too much than too little!
Defragmenting the hard disk drive using any utility software such as Utility always depends on the capacity of the hard disk drive and the overall speed of the computer system. For instance if your hard disk drive has 1 terabyte of storage space, it has a longer time to take it to be defragged compared to 100 gigagbytes.