LM3524D as a StepUp regulator
Both the TIP48 and the 1N4001 are poor choices for a switcher: they're not fast enough. Switching has to occur fast if you want the coil's voltage to swing high when you cut off the current. A Schottky diode is better than the 1N4001, first because Schottky's don't have a reverse recovery time, and also they have a lower voltage drop, which improves efficiency.
The TIP48 has a transition frequency of only 10 MHz, what you need there is a switching transistor.