Trying to center align button in td
I found that I had to combine the following attributes to center JSF controls on a page:
<h:form style="display: block; text-align: center; margin: auto; width: 200px">
<!-- components here -->
</h:form>
As I said in my comment above simply change the TD to have the align="center" property.
<td align="center"></td>
Since posting this I've discovered that this is deprecated in HTML5 so best just to use "text-align: center" on the TD in your CSS>
This worked for me
<td style="text-align: center">
You can use :
display: block;
margin: auto;
Here is your updated plunkr