| Rectorite is a mineral with specific texture. In order to find ways to use the rectorite friendly environment, we present a method formation of rectorite, synthesis and characterizations of aluminum-pillared rectorite, and adsorption capacity of pillared rectorite to ammonia, phosphate, COD, acid blue, in this paper. We also present the catalytic characteristics of pillared rectorite immobilized with SiW12-Heteropolyacid. The main conclusions are as follows:⑴ Natural rectorite, whether Na-rectorite or Ca-rectorite, is easy to scatter and form gel solution with water. We found that rectorite became easy to separate with water after calcination and pillaring. It means that calcined and pillared rectorite could be better than natural rectorite used to treat wastewater.⑵ We present the synthesis and characterization of aluminum-pillared rectorite. The synthesis was conducted with both conventional heating and microwave irradiation. Microwave irradiation was found to enhance the intercalation and ion-exchange during synthesis, and produced rectorite with larger d001 and better uniformity. The specific surface area is 180m2/g and basal spacing is 3.2 nm. The optimized synthesis conditions with microwave irradiation are:Rectorite slurry was 4%(wt), concentration of aluminum was 2.5 mol/l, ratio of rectorite with aluminum was 4mmol/g(dry base), microwave reaction time was 7 min.We found main factors that affect synthesis with conventional heating are concentrations of rectorite slurry and aluminum gel.⑶ The adsorption capacity of modified rectorite with calcinations, pillaring and formation to NH4+,Cd2+ were studied. The results show that mechanism of removal ion like NH4+ and Cd2+ is ion-exchange with modified-rectorite. Saturated rectorite can be reprocessed with hydroxy. Rectorite calcined at 300℃ for 3h has stronger adsorption to Cd2+, and its isotherm fit Freundlich equation.⑷ The adsorption capacity of Ca-rectorite , Na-rectorite and modified rectorite with calcination and pillaring towere tested. The results show that both calcinations and pillaring can improve capability of modified rectorite to adsorb F-. After calcinations, Na-rectorite has larger capability to adsorb F- than Ca-rectorite.⑸ For the purpose of removal trace phosphates from water body, we test the capability of modified rectorite. The results show that both calcinations and pillaring can improve capability of rectorite to adsorb phosphates. Calcined rectorite at 500℃ for 3h has largest adsorption to phosphates from 200℃ to 800℃. We found that hydroxy and F- reduce the adsorption capability of modified rectorite, and that both ammonia and COD increase it under the same conditions. [6] Removal of acid blue GL from water by using modified rectorite was investigated. The results show that modified rectorite both organorectorite and pillared rectorite have strong adsorbed capacity to adsorb acid blue GL. The adsorbed capacity of organorectorite and pillared rectorite reached 18mgg-1 and 21mgg-1 for acid blue GL, respectively. Adsorption isotherms both of them fit Freundlich equation. Al-pillared rectorite has characteristics of larger adsorbed capacity, low cost, high speed adsorbing rate, capable of regeneration compared with CTMAB-rectorite. [7] A new type solid acid of SiW12/P-Rec was prepared through impregnation method and used to catalyze the esterification of acetic acid and butanol. XRD, IR are used to characterize supported catalysts with different loadings and calcined at different SiW12 immobilized on P-Rec. And in the esterification of n-butanol by acetic acid, it can be found that the loaded amount of SiW12 and calcination temperature have a significant effect on catalytic property.As above all, cross-linking can increase specific surface area, basal space, change the interlayer properties; improve adsorption capacity to ion and organic materials of rectorite. Hence, it can be used as adsorbents to treat wastewater that contains ion and organic materials. Meanwhile, owing to its high thermal stability, pi...
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