Выборка CIBlockElement

<?require($_SERVER["DOCUMENT_ROOT"]."/bitrix/modules/main/include/prolog_before.php");

Bitrix\Main\Loader::includeModule('iblock');

$catalog = Bitrix\Iblock\ElementTable::getList([
  'select' => ['*', 'SECTION_' => 'IBLOCK_SECTION'],
  'filter' => ['IBLOCK_ID' => 1, '!IBLOCK_SECTION_ID' => false]
])->fetchAll();
echo "<pre>"; var_export($catalog); echo "</pre>";
// в $catalog[0]['SECTION_NAME'] будет название раздела