oh okay. So we won't need wow for it.

First solution - pure hover :

<i class="fa fa-pencil swing green-text"></i>

It is enough to call animation on hover event :

.fa-pencil:hover {animation: swing 1s linear .5s infinite;}

Second solution - jQuery (we just toggle animation on mouseenter/mouseleave events) :

$('.fa-pencil').on('mouseenter mouseleave', function (evt) {
  if (evt.type === 'mouseenter') {
    $(this).css("animation", "swing 1s linear .5s infinite")
  } else {
    $(this).attr('style', '');
  }
});