Calcite　is　one　of　the　most　common　gangue　minerals　in　mineral　processing.　The　efficient　separation　of　calcite　from　valuable　minerals　has　long　been　a　focus　and　challenge　in　the　field　of　mineral　processing,　and　especially　in　the　processing　of　calcium-containing　minerals　such　as　scheelite,　fluorite,　and　apatite.　In　acidic　pulp,　calcite　could　react　with　hydrogen　ions　to　form　CO2　bubbles,　which　are　sometimes　beneficial　for　minerals　separation.　The　process　of　CO2　bubble　generation　by　the　reaction　between　calcite　and　sulfuric　acid　was　systematically　studied　using　high-speed　camera　in　this　work.　The　effect　of　sulfuric　acid　concentration　and　calcite　particle　size　on　CO2　bubbles　production,　bubble　growth　rate,　detachment　diameter,　quantity　distribution,　apparent　specific　gravity　of　calcite　particles　and　surface　morphology　after　reaction　of　calcite　with　sulfuric　acid　were　investigated.　When　calcite　encountered　acid,　CO2　bubbles　generated　immediately　on　the　surface　of　calcite.　Once　grew　to　a　certain　size,　these　bubbles　would　detach　quickly　from　the　calcite　surface.　When　sulfuric　acid　concentration　was　in　the　range　of　1.0wt%~2.0wt%,　CO2　bubbles　production　on　the　calcite　surface　was　inversely　proportional　to　sulfuric　acid　concentration.　The　higher　the　concentration,　the　less　CO2　bubbles　was　produced,　and　the　faster　the　reaction　terminated.　As　sulfuric　acid　concentration　increased,　the　bubble　growth　rate　increased　and　the　detachment　diameter　reduced.　The　surface　of　the　calcite　would　always　adsorb　CO2　bubbles　during　the　reaction　time,　resulting　in　a　smaller　apparent　weight　of　calcite　and　the　change　of　surface　properties　of　calcite.　Calcium　sulfate　crystals　were　formed　by　the　reaction　of　calcite　with　sulfuric　acid,　which　prevented　the　further　reaction　of　calcite　with　acid.　The　apparent　specific　gravity　of　calcite　varied　with　the　particle　size,　but　only　at　small　values　of　6~7　seconds.　The　research　of　this　work　provided　a　fundamental　basis　for　the　separation　of　calcite　from　other　non-carbonate　minerals.　©　2020,　Science　Press.　All　right　reserved.