The Preparation And Performance Of Inorganic Humidity Controlling Materials

This text has studied the humidity-control performance of mineral material-zeolite which has natural nanometer drill way. Its microstructure was adjusted by acid-activation and heat-activation and the experimental parameters optimization was carried out, the preferable humidity-control zeolite material was gained. On the other hand the mesoporous silica Was synthesized in acid and alkalescence medium which was chose the hexadecyltriethylammon um bromide (CTAB) as the template at room temperature, and then silica was been modified by adding 1,3,5-Trimethylbenzene (TMB). Study on relationship between microstructure of these materials and their self-humidity-control performance were carried out as well as studied on the inorganic material humidity-control theory.Zeolite humidity-control materials have been made through optimizing raw zeolite, kind of acid, acid concentration, gravimetric ratio of zeolite to acid, acid-activation time and temperature; heat-activation temperature and time. It proves to that, the acid-activation and heat-activation parameters are: clinoptiloite, 7% sulfuric acid, 1:5, 90℃, and 1.5 hour; 300℃and 3 hours. And the maximum amounts of water adsorbed rate are 6.643% and 5.414% which are advanced from the primary is 3.569% while the maximum amount of water desorbed rate is -3.942% and -3.209% from the primary is -0.333%.Mesoporous silica has been synthesized by template: (1) acid medium, the molar composition of the incipient mixture is 1TEOS:0.12CTAB:9HCl:130H₂O. (2) alkalescence medium, the molar composition of the incipient mixture is 1TEOS:0.12CTAB: 0.16 NaOH:130H₂O. The SH-2 and SOH-3-2 have been obtained by the heating-up rate is 2℃/min at 550℃for 6h which have well humidity-control performance. And which can be modified by adding TMB when the mol ratio of TMB and CTAB is 2 could improve the adsorption and desorption ability. The Mesoporous silica that has excellent humidity controlling quality has been gained.The theory of inorganic humidity controlling materials adsorbing water molecule can be explained by the solid surface absorption and capillary condensation effect, the microstructure, surface area, pore volume and pore distribution are the main factors influencing its humidity controlling performance. The moisture absorption ratio of humidity-control minerals augments along with the surface area and pore volume, the moisture desorption ratio increases in company with pore volume, and the more hole with aperture distributing in 3～5nm, the better of their humidity-control performance. And at medium RH (40%～70%), which is suitable for human most, the pore distribution at aperture is 3.35～7.40nm.