The Modification Of Activated Carbon Fiber And Its Analytical Application Studies

In this thesis, activated carbon fiber (ACF) as a new adsorption material was modified by grafting amide and loading TiO₂ onto its surface, respectively. The aim of the modification is to adsorb, separate the inorganics and degrade organic compound in environmental Wastewater. Our researches have acquired some primary consequence. The main contents are listed as follows:1. The nano-sized titania (TiO₂) powders were synthesized at low tempereture by direct hydrolyzation method and loaded on ACF simultaneously in the reactor. The properties of the TiO₂/ACF combined photocatalyst were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photo spectroscopy (XPS) and thermogravimetry-differential thermal analysis (TG-DTA). SEM photos showed that the particles of TiO₂ aggregated into clusters and were fixed on the surface of ACF. From the XRD results we can found that the crystalline patterns of immobilized TiO₂ before and after calcination were rutile phase and their microcrystalline size was 7.02 nm and 9.88 nm, respectively. The quantity of TiO₂ loaded on ACF was around 0.88 g/gACF according the TG analysis. XPS results suggested that titanium really existed in the form of Ti⁴⁺ (TiO₂). TiO₂/ACF's photocatalytic degradation ability was studied using alizarin red S (ARS) as the target organic pollution without sparging air into the solution. The degradation experiments of ARS and cycling usage of photocatalyst indicated that the combined photocatalyst had good photocatalytic reactivity. This kind photocatalyst combined ACF's strong adsorption ability and TiCVs good photocatalytic reactivity perfectly. This method is of ease, convenience and low cost.2. The modification of ACF by two-step organic reaction of acylation and ammonolysis was carried out, which is never been reported before. It was obvious that amide was successfully grafted onto the surface of ACF according to the results of FT-IR and XPS. In the disposal of Cu²⁺, ACF before and after grafting was applied as its sorbent and ICP-AES was utilized to detect the change of Cu²⁺, concentration. Comparing the maximal adsorption capacity q_max, we found that the modified ACF had the higher adsorption capacity; its q_max value was about 1.5 times higher than the unmodified one's. The enhancement can be ascribed to the formation of coordination bond between N atom and Cu²⁺.