Research On Adsorption/Desorption Properties By Lignocellulose Based Nanocomposite Adsorbent For Dye

The cellulose-g-polyacrylic acid/acrylamide/montmorillonite nanocomposites adsorbent (LNC-g-PAA/AM/MMT) were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transimission electron microscope (TEM) and scanning electron microscope (SEM). Discussed to the effects of different monomer ratio of acrylic acid (AA) and acrylamide (AM), neutralization degree of AA, monomer concentration, initiator concentration, crosslinking agent, montmorillonite (MMT) content and other reaction conditions on the nanocomposite superabsorbent resin adsorption different cationic dye adsorption performance influence. Determine the three-dimensional network of nanocomposite superabsorbent best preparation conditions. At the same time the best preparation conditions in the different adsorption conditions were researched such as the initial concentration of dye solution, adsorption time, adsorption temperature and dye solution PH value and so on. And the adsorption kinetics and adsorption isotherm were studied. In addition, on the basis of the optimum adsorption conditions, a preliminary study of the three-dimensional network of nanometer composite superabsorbent desorption performance were studied. To investigate the influence of hydrochloric acid concentration, desorption temperature and desorption time, desorption conditions established for LNC-g-PAA/AM/MMT nanocomposite desorption properties of superabsorbent resin. To determine the best and explore its adsorption desorption condition renewable.The research results of this paper were summarized as follows:1. The effect of different preparation conditions on adsorption capacity of the LNC-g-PAA/AM/MMT nanocomposite adsorbent for methylene blue (MB) and fuchsin basic (FB) dye was studied and the structure of the adsorbent had been characterized. At the same time, the adsorption and desorption behavior of adsorbent for MB and FB dye, the adsorption kinetics and isotherms were also studied.The characterization results showed that LNC-g-PAA/AM intercalated into montmorillonite interlayer via destroying the crystalline structure of montmorillonite, and the intercalated-exfoliated structure was formed in LNC-g-PAA/AM/MMT nanocomposite. LNC-g-PAA/AM/MMT with better thermal stability than LNC-g-PAA/AM. The best preparation conditions of LNC-g-PAA/AM/MMT nanocomposites adsorbent for the removal of MB and FB from aqueous solution were studied. The results indicated that acrylic acid(AA) to acrylic amide (AM) monomer ratio of8:1, monomer concentration for24%, neutralization degree for50%, content of initiator for0.3%, crosslinking agent content for0.03%, MMT of nanocomposite hydrogels25%, the adsorption capacity of LNC-g-PAA/AM/MMT nanocomposites adsorbent for MB was achieved2038.7mg/g and FB was achieved2912.65mg/g under the optimum preparation conditions, respectively.2. Adsorption experiment in the best preparation conditions were researched the adsording capacity of LNC-g-PAA/AM/MMT nanocomposites adsorbent for MB dye, FB dye, mixed dye MB and FB dye. And discussed adsorption kinetics and adsorption isotherm of MB and FB dye.Adsorption experiment which was in the different adsorption conditions of MB was discussed such as the initial concentration, adsorption time, adsorption temperature and the dye solution pH value and so on. LNC-g-PAA/AM/MMT nanocomposite adsorbent was applied as adsorbent for the removal of MB dye adsorption amount of influence. The result showed that:The initial concentration for2500mg/L; the adsorption time for120min; adsorption temperature reach30℃; pH value reach5; the obtaining nanocomposite adsorbent showed the high adsorption capacity2038.7mg/g. It was showed that all the sorption processes were better tallied by pseudo-second-order equation and the Langmuir equation.Adsorption experiment of FB was discussed in the different adsorption conditions such as the initial concentration of dye, adsorption time, adsorption temperature, pH value and so on. LNC-g-PAA/AM/MMT nanocomposite adsorbent was applied as adsorbent for the removal of FB dye adsorption amount of influence. The results showed that:The initial concentration for3250mg/L; the adsorption time for120min; adsorption temperature reach30℃; pH value reach5.5; the obtaining nanocomposite adsorbent showed the high adsorption capacity2912.65mg/g. It was shown that all the sorption processes were better tallied by pseudo-second-order equation and the Langmuir equation.Adsorption experiment was studied in the different adsorption conditions such as the mixed dye solutions initial concentration, adsorption time and adsorption temperature, mixed dye pH value and so on. LNC-g-PAA/AM/MMT nanocomposite adsorbent was applied as adsorbent for the removal of MB and FB mixed dye adsorption amount of influence. The results indicated that:The mixed dye initial concentration rate of MB/FB for2/3, initial concentration in the mixed dye solution for1800/2700(mg/1); the adsorption time for120min; adsorption temperature reach30℃; pH value reach5.5; LNC-g-PAA/AM/MMT nanocomposite adsorbent showed the high adsorption capacity. The adsorbent adsorption for MB dye of1295.6mg/g and FB dye of2547mg/g.3. The effect of different desorption conditions such as hydrochloric acid concentration, desorption temperature and desorption time on MB and FB dye desorption rate of the LNC-g-AA/AM/MMT nanocomposite adsorbent and renewable were studied.Desorption results indicated that the desorption efficiency by the oscillator and the ultrasonic was73.16%and73,23%, using0.05mol/L HCl, desorption temperature30℃and desorption time of the oscillator for120minutes and the ultrasonic-wave for30minutes. Circulation desorption adsorption experiments showed that: LNC-g-PAA/AM/MMT nanocomposite adsorbent can cycle adsorption-desorption four times, the rate of desorption remains above61.9%.Desorption results indicated that:the desorption efficiency of LNC-g-PAA/AM/MMT nanocomposite adsorbent for FB was73.22%, using0.075mol/L HC1, desorption temperature30℃and desorption time120minutes. Circulation desorption adsorption experiments showed that:LNC-g-PAA/AM/MMT nanocomposite adsorbent can cycle adsorption-desorption four times, the rate of desorption remains above65.24%.