Is there any simple methods available to replace sodium in the zeolite with Hydrogen ion without damaging the zeolite structure?

Exchanging Na ions by NH4NO3 solution (0.1 M), filtering, washing, drying, and then calcination at 400 oC for decomposition of NH4NO3, resulting in formaiton of proton within zeolite.

yes, yes

you Use NH₄NO₃ or Cr(NO)₃·H₂O or KOH and or .... for ion-exchange

Because Al-Si struture within zeolite could be destroyed by strong base, KOH is not used to exchanged ions. KOH, K2CO3 or NaOH in deluted solution is commonly chosen to create larger pore by chemically etching. If Cr(NO)3·H2O is used, Cr ions is possibily residual in zeolite, so I still suggest to use ammonium salt which could be thermally decomposed and result in proton.

Stability of zeolite structure depends on type of zeolite and Si/Al ratio. Zeolites as Y-type with Si/Al about 2.5-3 are very sensitive to action of even diluted mineral acids (collapse os structure), and H-form is necessary to prepare by REPEATED treatment with 1M HN4NO3 (depending on the desired degree of decationization even 5-10 times) and by thermal treatment MH4-form to convert ino H-form. Zeolites as mordenite with Si/Al=5 and more are stable in acid solution, but besides of decationization even partial dealumination proceeds without collapse of structure. Zeolites with high Si/Al ratio over 15-20 as ZSM-5 zeolites are very stable in solution of mineral acid (e.g. 0.5 M HCl), decationization could be realized without observable dealumination.

But, in all cases it is necessary to take into account content of sodium in parent zeolite, and desired degree of decationization - for zeolites with low Si/Al ration the higher content of Na it is necessary to exchange by repeated treatment with NH4NO3. Ion exchange is process that proceeds into equilibrium between solid phase (zeolite) and liquid phase (solution).

The use of KOH for preparing of H-form is nonsens from two points of view - you partially could exchange Na by K, that is not proponic form, and mainly, zeolites are very unstable in alkaline solutions.

maybe you can check this article Aboobucker Sithique Mohamed :

Synthesis and Characterization of Zeolite Na–Y and Its Conversion to the Solid Acid Zeolite H–Y