<?php
$path_file = 'file.txt';
$file_contents = file_get_contents($path_file);
$path_json = 'array.json';
$read_json = file_get_contents( $path_json );
$array_json = json_decode( $read_json, true );

$data=$array_json;
function batchChange( $data, $level)
{
    global $file_contents;
    foreach( $data as $key1 => $value1 )
    {
        $file_contents = str_replace($key1,$value1,$file_contents);
        echo $file_contents .  "<br />";
    }
}

echo "<pre>";
batchChange( $data, 0 );
echo "</pre>";
file_put_contents("file_new.txt",$file_contents); // write permissions !

// file.txt looks like this
old red dry shoe

// array.json looks like this
{
    "old": "new",
    "red": "blue",
    "dry": "wet",
    "shoe": "hat"
}

?>