Research On Preparation, Adsorption And Photocatalytic Properties Of Compound Cucurbiturils

Cucurbiturils (Q [n]) with special structure and stable chemical properties hasunique advantages in the field of water treatment. However, after reaching adsorptionsaturation, it’s difficult to separate from wastewater so that limits its further application.Magnetic cucurbiturils was got by Fe3O4and Q [8] to solve this problem and itsadsorption behavious of three kinds of phenolic compounds were studied systematically.In addition, CdS has attracted much attention in the field of photocatalysis as its visiblelight response, but it easy to corrosion under light and hole-electron also recombinationeasily so that affect the photocatalytic efficiency. Therefore, by combining Q[5] ascarrier with CdS, the separation of photoelectrons from vacancies can be effectivelypromoted and it was used to degradate methylene blue.Specific content as follows:1. Fe3O4/Q[8] composite adsorbent was prepared by solvothermal method. Theeffect of different proportions of Fe3O4and Q[8], reaction temperatures and time on thesurface morphology was investigated. It was found that it has little effect on itsmorphology. The material was characterized by X-ray diffraction (XRD), scanningelectronmicroscopy (SEM), fourier transform infrared spectroscopy (FT-IR) andthermalgravimetric analysis (TG-DSC), respectively, indicating that they were heldtogether by hydrogen bonds. Composite adsorbent have paramagnetism by VSManalysis which realized the fast separation of cucurbiturils from solution.2. The removal of bisphenol A,2-naphthol, phenol from aqueous solution byFe3O4/Q[8] composite adsorbent was explored by ultraviolet spectrum. Fe3O4/Q[8]demonstrated good adsorption capacity. The maximum capacity of bisphenol A,2-naphthol, phenol at percentage of adsorption are95.6%、85.3%、54.2%，respectively, when composite adsorbent dosage, phenolic compounds concentration, temperature, pHand time are0.0800g,30mg·L-1,298.2K and360min. The composite adsorbent dosageand pH have great influence on the removal rate among those factors. Besides, differentanions have different influence on the removal rate. Adsorption isotherm could be wellinterpreted by Langmuir, Freundlich and Tempkin isotherm. The calculation ofthermodynamic functions indicated that adsorption process was spontaneous andexothermic. Adsorption Kinetic followed pseudo-second-order kinetics which indicatedthat the limit factor of adsorption HA was adsorption mechanism. Moreover, theadsorption capacity of Fe3O4/Q[8] was also above90%after being used for four times.3. The spherical CdS/Q[5] composite photocatalyst was prepared by water bathdeposition with the particle size of about200nm. Compared with pure CdS, thedegradation rate can reach99.3%increasing by58.8%when the compound amount Q[5] is55%, the dosage of CdS/Q [5] is0.1000g, initial concentration of methylene blueis10mg·L-1. The interaction and separation of electronic-hole between CdS and Q [5]were contained by fluorescence spectrum. The catalytic capability of CdS/Q [5] wasalso above93.6%after being used for four times.