Here is some information to help you.
You need a enzyme cleaner.
Here several Hometalkers shared their ideas:
Odoban is best for any smell, we used if on an old animal control building at my work. Here is the link to the one I have used.
One solution is to use an enzyme cleaner from the pet store. Miracle Method is one. Another solution is to sprinkle baking soda all over. Then spray vinegar and let it foam. Rinse well.
Hi Hector, sorry you have cat urine smell on your patio furniture. Hope this help you fix the problem. Good luck. 10 Tips for Cleaning Cat Urine | Animal Planet
May 14, 2013 - If your cat is sick, has behavioral issues, is getting used to a new pet or child, or is ... We're sharing 10 tips for cleaning cat urine and preventing your furniture from being given ... Work the baking soda into the fabric or carpet.
Hello Hector: I have used a product called Odormute. Pet Supplies Plus used to carry it, but I'm not sure now. You can get it online. You need a product that will change the chemical properties of the urine, or an enzyme eater. Also, Odormute will clean the spot. I have used it for years and have not been disappointed. Even on cat pee stains that were over 16 years old under a carpet, through the padding, in a corner and onto the wooden floor. Never knew the cats were using that area:( AC takes care of a lot of smells. Also cleaned and whitened my son's baseball pants. The cats peed on them and I found out a year later (they were in a box) and the pants came out white and stink free. The stuff seems expensive, but you just use a little bit. It's environmentally safe, you can use it on your pet for skunk smells, and it's made in the USA! Doesn't get any better than that.
Good luck with whatever you use.
Hello....what I swear by believe it or not is the brown ( brown only) mouth wash that you buy at the Dollar Store. Only use the brown kind though! The other flavors will attract ants! The mouth wash will also clean and disinfect. I use it inside and outside for cat urine, dog urine, human urine around the floor when someone misses the toilet.... it works great! Just soak the cushions and let them sit(out of the sun) for about a half hour or if you have a cleaning machine...put the mouthwash in the machine (NO DILUTING MUST BE STRAIGHT MOUTHWASH)and use as usual. (NOTE:I have used this for years and have never had it ruin a machine). Hope this helps someone.
Vinegar and Unsweetened Lemon Juice. The Lemon juice is for the Scent.
Cover the affected areas with clumping (scoopable) cat litter and let sit for 24 hours. Sweep. The litter contains charcoal and other substances that neutralize the urine. NOTE: place citrus peels around to keep cats away...they hate the scent.
I used Natures Miracle. It is the only thing I could find that worked. https://amzn.to/2TC1rrJ