What is the diffrence of a 19MM bottom bracket and a 22MM bottom bracket?

The difference is the size of the hole in the center of the bearing. A 19mm bottom bracket will fit a 19mm crank spindle (profile cranks have a 19mm spindle). A 22mm bottom bracket will have a hole in the center that is 22mm. a 22mm spindle (eclat tibia cranks have a 22mm spindle) will fit in the 22mm bottom bracket. The size of the bottom bracket needed depends on the size of your crank's spindle size.