Need to write a script to remove old products from the site 1C Bitrix

Good day! You need to address a number of issues with the upload of the website on 1C Bitrix. (Unloading on the side of the site is configured)

1.The site has a directory. In a catalogue produced by unloading of goods from 1C.
The catalog website has the goods not unloaded from 1C, with zero balances and so on. On the side 1S all right. Goods catalog of more than 200,000 pieces. You need to write a script that will pass the catalog on the website and remove the products with the specified parameters (date, etc.)

2.You need to complete when unloading on the site deaktivirati or removed products that are not available in this discharge. Using the standard import to achieve this does not work..