I'm sure Tesco used to have a recycling scheme. just take your old cartridge and drop it into Customer Services when you get your groceries.
I don't know whether they still do that as my use of inkjet cartridges has dropped to almost nil since acquiring a laser printer - which I do refill myself. The occasional colour photo is about all I print in colour now.
I can't see any recycling scheme being successful if it costs money, even just a stamp, to take part.