PCDATA invalid Char value 1 — ошибка при чтении XML

$text=preg_replace('/[^\x{0009}\x{000a}\x{000d}\x{0020}-\x{D7FF}\x{E000}-\x{FFFD}]+/u',' ',$text);

function prepare_to_xml($text){
	$text=preg_replace('/[^\x{0009}\x{000a}\x{000d}\x{0020}-\x{D7FF}\x{E000}-\x{FFFD}]+/u',' ',$text);
	$text=strip_tags($text);
	$text=htmlspecialchars($text);
	$text=str_replace("\t"," ",$text);
	$text=str_replace(" "," ",$text);
	$text=str_replace(" "," ",$text);
	$text=preg_replace("/[\r\n]+/i","",$text);
	$text=preg_replace('/ {2,}/',' ',$text);
	$text=trim($text);
	return $text;
}

function utf8_for_xml($string){
	return preg_replace('/[^\x{0009}\x{000a}\x{000d}\x{0020}-\x{D7FF}\x{E000}-\x{FFFD}]+/u',' ',$string);
}