Studies On Modified Mechanism And Catalytic Activity Of Bentonite

Bentonite is one kind of mineral clays contaimng the aqueous alun-unosihcate and there is abundance storage in our country As it shows some special physical and chemical properties, it is widely used in industrial and agricultural production At present, most kinds of bentonite products are primary ones in inland The kinds of modified bentonite products are very few In order to make the best use of our country's bentonite resource, developing new type of modified bentonite products have become an important role in the research project of our country's bentonite production By use of its interbedded dilatability and cation exchange capacity, bentonite can be modified to bentonite catalyst by some ways, such as activation,being supported and cross-linked Comparing with liquid acid catalyst, bentonite catalyst has many advantages For example, bentonite catalyst would not only make itself more useful in acid-catalyzed reaction, in which the catalyst is often difficult to be separated from the reaction products, but also meet the conditions for utilizing the new technology of catalytic distillation So there is a perspective application of the modified bentonite catalyst in organic chemical reactions In this paper, Ningming bentonite, as raw material, was modified by some kinds of ways such as purifications sodium chloride treating and acid treating Finally on the basis of atlapulgite, hydroxyl-Zr cross-linked bentonite and La-loaded bentonite ware prepared The esterifyrng catalytic activity of modified bentonite ii catalyst was measured Bentonite catalyst was also characterized by XRD,potentiometric titration,SEM and BET measurement Base on the experiment results,the effect of catalySt's prepndlon factors on catalyst's esterifylng catalytlc actlvltyand physlc-chemlcal propCrtes were dlscussed The best preparat1on condltlons ofhydroxyl-Zr cross-llnked benionlte and La-loaded bentonlte were obtained Theresults show that hydroxyl-Zr cross-l1nked belltonlte and La-loaded belltonlte havegood esterfylng catalyt1c actlv1ty Physlcal chemlstTy propertles of the catalyst are alldributed to the lncrease of catalytlc estenficatlon actlvlty of bentomte Its sdseacld1ty played a more lmportam ro1e than the other factors ln the cataly'tlcestenficatlon The results of eStCrfying catalyst preparatlon glve an expenmentalbasls of Nlngmlng befitomte modlficat1on...