We were doing basic radical analysis in lab and we were asked to add aqua regia on the filtered PPT collected on the filter paper and collect the formed solution , my question is if aqua regia can dissolve even gold and platinum why didn't it burned the filter paper(or made holes in it )
For "burning" of paper by sulphuric acid, the better term would be "aggressive dehydration".
Note that aqua regia is rather a diluted acidic mixture without significant dehydrating or oxygen based oxidation behaviour, but manifests aggressive chloration behaviour, that dissolves precise metals.
Cellulose has quite good endurance against chlorine, which is used in various solutions for cellulose whitening.
Concentrated and strong acids like sulfuric acid are substances that extracts water anywhere and everywhere to react with and make H3O+ ions. They are even able to extract water from the cellulose of the paper, as cellulose is made of carbon plus water. So a drop of sulfuric acid on paper burns it, or rather transforms it into charcoal. The word "burn" is not appropriated, Aqua regia and concentrated hydrochloric acid will never do it, as these liquid substances are made of more than 50% water.