Dear Muhammad Ashraf many thanks indeed for your interesting technical question. This is certainly an important question in view of the fact that palladium is rather expensive. There are various methods reported on the literature to recover palladium metal from waste solutions. In this context I would recommend to have a look at the following articles entitled

1. Recovery of palladium and silver from process solutions by precipitation with thiocyanates and iron cyanides

Article Recovery of palladium and silver from process solutions by p...

2. Palladium(II) Recovery from Hydrochloric Acid Solutions by N,N′-Dimethyl-N,N′-Dibutylthiodiglycolamide

This article is Open Access and can be freely downloaded from the general internet. For your information please find attached a pdf file of this paper.

3. Recovery of Platinum and Palladium from Chloride Solutions by a Thiodiglycolamide Derivative

https://www.tandfonline.com/doi/abs/10.1080/07366299.2013.810969?journalCode=lsei20

4. A study of palladium recovery with thiourea from nitric acid solutions

Article A study of palladium recovery with thiourea from nitric acid solutions

Please note that there are many more articles on this topic available from the general internet. I also suggest that you use the "Search" function of RG to find other relevant articles. Just search for "palladium recovery" and then click on "Publications".

Please see also the following very very new method

Article A New Method of Determining Palladium

1-Spectrophotometric method for palladium determination using ...

http://chemetal-journal.org › ejournal14 › CMA0279

PDFby L LOZYNSKA · Cited by 3 — The method is based on the interaction of palladium(II) ions with 5-hydroxyimino-4-imino-1,3-thiazolidin-2-one at pH = 5.0, in a medium of acetate buffer

2. Gravimetric determination of palladium with di-2 ...

https://scholar.uwindsor.ca › cgi › viewcontentPDFby JT Gerard · 1968 — used to set up a gravimetric procedure for determining gold in the

Thank you very much