SAP NW RFC PHP EXTENSION

Hello!

I can't figure this out:

I have a Centos 7 server with apache 2.4.6 and php 7.2.12.

I followed the instructions from here

https://gkralik.github.io/php7-sapnwrfc/installation.html

and here

https://gkralik.github.io/php7-sapnwrfc/building.html#building-on-linux

The php sapnwrfc.so extension built succesfully, it appears if I run php -m with no error.

But if I try to access my index.php from browser httpd error log shows:
LD_LIBRARY_PATH is currently set to <not set>

Please help me! What am I doing wrong?

Thank you!