Adsorption Performance Of O-quaternary Ammonium Salt Modified Chitosan Cyclodextrin And Its Application In Drilling Wastewater Treatment

This paper mainly focus on the adsorption properties of O-HTACC-g-CD to the phenolic substance and metal ions,as well as the possible application in the drilling waste water,in particularly,there is less study about the application of chitosan bearing cyclodextrin in the drilling waste water treatments,which exhibits great significance in the oil field waste water treatment.In this paper,the chitosan bearing ?-cyclodextrin(CTS-g-CD)was obtained through Williamson ether synthesis,and in order to increase the surface hydratability of the target product,as well as improve its dispersibility and swelling property,3-chloro-2-hydroxypropyl trimethyl ammonium chloride(CTA)was brought to modified the chitosan's C6-OH to obtained the O-quaternary ammonium salt modified chitosan bearing cyclodextrin(O-HTACC-g-CD)product,and the content of P-cyclodextrin was 31.4087?mol/g which was measured by the colorimetric method,and the O-HTACC-g-CD was characterized by Fourier transforms infrared(FT-IR),Nuclear magnetic resonance(NMR),X-ray diffraction(XRD),Scanning electron microscope(SEM)and Thermo gravimetric-Differential scanning calorimeter(TG-DSC).Then,this paper mainly focused on the adsorption properties of O-HTACC-g-CD to phenol and Cr(III)in different conditions.On the foundation of single factor experiment including different pH,adsorbent dose,temperature and time,as well as the principle of BBD model,the design of three factors and three levels response surface analysis was adopted to optimized the conditions of phenol adsorption at 25? and Cr(III)adsorption at 35? and the results exhibited that the O-HTACC-g-CD showed efficient phenol adsorption ability when the pH was 6,adsorption dose was 0.06g and adsorption time was 3.5h,as well as the good Cr(III)adsorption ability when the pH was 5,adsorption dose was 0.05g and adsorption time was 3h.Meanwhile,with the analysis of kinetics and thermodynamics of phenol and Cr(III)adsorption process,the results showed that both of these two processes followed the pseudo-second-order rate equation and Langmuir isotherm.Moreover,the thermodynamic parameter of phenol ?H°<0,?S°<0 and ?G°<0 meat this was a exothermal,extropy decrease and spontaneity process,and | H|>| TS | meant this adsorption process was enthalpy driven;the thermodynamic parameters of Cr(?)?H°>0,?S°>0 and ?G°<0 meant this was a endothermic,extropy increase and spontaneity process,and | H|<| TS| meant this adsorption process was entropy driven.In addition,the Energy dispersive spectrometer(EDS)showed that the chromium content was 2.87%,which could prove that Cr(III)was adsorbed onto the surface of O-HTACC-g-CD.In this paper,the adsorption process of O-HTACC-g-CD to the organics(COD value was the main index for organics.)and metal ions in drilling waste water were investigated.According to the results of single factor experiment,O-HTACC-g-CD exhibited optimum adsorption capacity to the drilling waste water when the pH was 4,adsorbents dose was 0.2g,temperature was 25? and adsorption time was 4h.Moreover,the Energy dispersive spectrometer(EDS)result could prove that O-HTACC-g-CD showed effective adsorption to the metal ion,organics,sulfide and inorganic substance.