azeotrope can't be distillation and normal solution can distill by simple heatup the solution

The azeotrope concentration of a water-xylene system is approximately 71.4% xylene and 28.6% water by weight at a temperature of 73.5 degrees Celsius. This azeotrope forms when the vapor and liquid phases have the same composition, making it difficult to separate the two components by distillation.

Yes, the boiling point of the azeotrope is 70.3 °C and contains 8.5 wt% water. see: http://www.solvent--recycling.com/azeotrope_1.html

It forms an azeotrope.

Pressure Swing Adsorption refers to the process of purification of Hydrogen gas which is manufactured in a plant like rfinery. Hydrogen which is formed as a by-product in process like Reforming is also used as a raw material within the refinery process like Hydrotreating and Isomerization. So it has to be made impurities free for use. So Hydrogen is purified by the process known as pressure swing adsorption in which impurities are adsorbed on the surface and Hydrogen becomes clean.