If you have enabled B2B Catalogs on any of your themes and want to uninstall the App from your store, you 

B2B Catalogs from any themes it is currently enabled on.

 B2B Catalogs for a theme, open the App within the Shopify admin and click the "disable" button on any currently enabled themes.

Once all themes have been disabled, you can uninstall the B2B catalogs app.

You will need to re-install the app temporarily and follow the instructions above.

B2B Catalogs is a free SparkLayer app that gives you control over which products are visible to different types of customers on your Shopify store.

Limitations

Removing B2B Catalogs