PHP: how to directly convert xpath to node/attribute

I wonder if in PHP there is a direct way (without iterations) to convert xpath, say:

component_volume_concentration/component[1][@formula="CH4"]
component_volume_concentration/component[1][@unit="%"]
component_volume_concentration/component[1][@min="22"]
component_volume_concentration/component[1][@norm="25"]
component_volume_concentration/component[1][@max="30"]

to XML node and attribute structure:

<component_volume_concentration> 
<component formula="CH4" unit="%" min="22" norm="25" max="30" />
<component formula="C2H6" unit="%" min="22" norm="25" max="30" />
<component formula="C3H8" unit="%" min="22" norm="25" max="30" />
<component formula="i-C4H10" unit="%" min="22" norm="25" max="30" />
<component formula="i-C5H12" unit="%" min="22" norm="25" max="30" />
</component_volume_concentration> 

Thank you!