Valonea　tannin-cellulose　composite　aerogel（VTCA）was　prepared　by　introducing　valonea　tannin　through　cross-linking　reaction　with　cellulose　as　the　raw　material，and　then　the　thiol-modified　cellulose-based　composite　aerogel（TVTCA）was　synthesized　by　introducing　thiol　functional　group　on　VTCA　through　esterification　reaction.　The　physicochemical　properties　changes　of　TVTCA　before　and　after　adsorption-reduction　were　analyzed，the　adsorption-reduction　effect　of　TVTCA　on　Ag（Ⅰ）in　water　was　investigated，and　the　mechanism　was　discussed.　The　results　showed　that　after　the　adsorption-reduction　of　Ag（Ⅰ），the　pore　structure　of　TVTCA　collapsed，as　well　as　the　thiol　group　and　phenolic　hydroxyl　group　underwent　adsorption-reduction　with　Ag（Ⅰ）.　Under　the　optimum　adsorption　conditions　of　pH　value=5，the　equilibrium　adsorption　capacity　of　TVTCA　for　Ag（Ⅰ）reached　111.　67　mg/g.　The　adsorption　was　consistent　with　the　pseudo-second-order　kinetic　model　and　the　Langmuir　isotherm　model.　It　was　a　chemical　adsorption　process　with　monolayer　adsorption，which　belongs　to　exothermic　reaction.　Additionally，the　influence　analysis　of　coexisting　ions　in　water　showed　that　the　adsorption　selectivity　of　TVTCA　was　enhanced　after　the　introduction　of　thiol　groups.　The　adsorption　of　Ag（Ⅰ）by　TVTCA　was　a　synergistic　action　of　electrostatic　attraction，chelation　adsorption　and　reduction.　Ag（Ⅰ）was　adsorbed　and　fixed　to　the　cellulose-based　aerogel　surface　of　TVTCA　through　electrostatic　attraction　and　chelation　of　—SH　and　phenolic　hydroxyl　group，and　85.　79%　of　Ag（Ⅰ）was　reduced　to　Ag0　through　phenolic　hydroxyl　group　from　tannin.　©　2025　China　Technical　Association　of　Paper　Industry.　All　rights　reserved.