There are several different cleansing diets that are citrus based. I'm not aware of one actually called 'citrus cleanse' however.
Once good one to cleanse the body of toxins is the orange cleansing diet. Basically you spend 2-3 days fasting and only consume fresh squeezed orange juice. You can eventually work up to a week but start with a couple days.
It is called The Master Cleanse or Lemonade Diet. Basically you drink a mixture of fresh lemon juice, maple syrup, cayenne pepper and water for 3 to 10 days. No food at all. There is a book called "The Master Cleanse".
There is no proven benefit to doing a "cleanse". There have been numerous studies done w/ 2 groups of people (1 group doing the "cleanse" & the other eating regular meals consisting of veggies, protein & carbs) & the cleanse people actually came out of it w/ lower metobolic rate from the "starving" of oneself..... Clearing is bs. Your body is already made to "cleanse" itself of toxins. Try "liver health" teas if u feel ur body isn't doing it's job.