The　adsorption　process　is　a　highly　efficient　and　widely　applied　fundamental　technique　in　the　field　of　Geo-environmental　engineering.　Most　existing　adsorption　models　are　empirical　or　semi-empirical　and　lack　a　consistent　and　unified　scientific　theoretical　basis.　In　this　work,　a　new　adsorption　kinetic　model　with　dispersion-type　(D-type)　has　been　proposed　within　the　framework　of　irreversible　thermodynamics　for　investigating　the　adsorption　behavior　of　a　single　ionic　species　onto　a　solid　adsorbent.　Based　on　Ziegler＇s　maximal　rate　of　dissipation,　an　expression　for　mass　exchange　rate　was　determined　after　a　detailed　theoretical　deviation　by　defining　the　thermodynamic　force　and　thermodynamic　flow;　and　by　formulating　two　dispersion-type　free　energy　functions　and　a　dispersion-type　dissipation　rate　density　function.　The　mass　exchange　rate　expression　was　introduced　into　the　mass　balance　equation　as　further　validation　of　the　D-type　adsorption　kinetic　model　for　a　single　system.　Comparing　the　adsorption　process　predicted　by　the　presented　model　with　the　tested　adsorption　processes　of　Pb2+　and　Cd2+　onto　beidellite　and　Pb2+　on　bentonite,　the　results　reveal　good　agreement　with　experimental　data.　The　D-type　adsorption　kinetic　model　could　provide　a　correct　description　of　the　kinetics　of　adsorption　process　for　single　ionic　species　onto　solid　adsorbent.