How to remove duplicate key value array in multidimensional array

[nilayadattract]

I have this array i want to remove array if it value are same from others

$appointments = array(
                      array('1','Monday', '5:30 PM'),
                      array('2','Friday', '6:00 PM'),
                      array('3','Monday', '5:30 PM'),
                      array('4','Tuesday', '4:15 PM'),
                      array('5','Wednesday', '8:30 PM'),
                      array('6','Thursday', '1:45 PM')
);

i want this result **Monday** and time is display two time so i have to display only one time i use below code for this so please provide better solution for this 
 
$one_dimension = array_map('serialize', $appointments);
$unique_one_dimension = array_unique($one_dimension);
$unique_multi_dimension = array_map('unserialize', $unique_one_dimension);
 
echo "<pre>";print_r($unique_multi_dimension);die;

[nilayadattract]

sollution of this is below,
thanks

$implodedColumns= array_map(function($data){
unset($data[0]);
return implode(“,”, array_map(‘trim’, $data));
}, $appointments);
$result=array_unique($implodedColumns);

array_walk($result, function(&$value,$key){
$value= array_merge(array($key), explode(“,”, $value));
});

print_r($result);