Here is a link to a procedure to produce HZSM-5:

http://www.ijnnonline.net/pdf_9097_883f0ab35db372ca7b19c940f3131d69.html

A high temperature calcination will do. (823K under flow air)

If you could not performed calcination then you could try to treat it with HCl, but be careful it can also result in a partial dealumination of the zeolite lattice. Suspend the sample in a 0.5 N HCl solution and stirred at, 353 K during at least 15 minutes: 10 ml of solution per gram zeolite. After filtering and thorough washing - repeated once again.

DOI: 10.6100/IR30334

Acid ion exchange at about 70 oC waterbath.

The procedure is given in this paper

Article Controlling the product selectivity in the conversion of met...

Calcination at 550 oC might be helpful.

http://www.rsc.org/suppdata/c6/ra/c6ra19035a/c6ra19035a1.pdf