| In this paper, four biosorbents were prepared from peanut shells by the modification. The characterization of the modified peanut shells was obtained using Raman spectra, FTIR, XPS and Microscope. The adsorption behavior of the four biosorbents for three proteins under the different conditions, including the effect of pH, contact time, protein initial concentration, NaCl concentration and temperature on adsorption capacity was investigated. Adsorption mechanism of protein was also preliminary studied. The major study works and results are as follows:1. The pristine peanut shells was obtained by crushing, selecting 100 to 120 purpose particles, washing and drying. The crosslinked peanut shells was obtained by adding 1.25 mol L-1 NaOH solution 80mL and epichlorohydrin solution 30 mL to 10.0 g peanut shells, controlling reaction temperature at 40℃, mixing time for 1 h, filtering, waterwashing and drying. The reactive green 19(RG19) modified peanut shells was obtained by mixing 0.5 g RG19 and 1.0 g crosslinked peanuts shells, controlling reaction temperature at 80℃, mixing time for 4 h, filtering, waterwashing and drying.The characterization of the modified peanut shells was obtained from Raman spectra and FTIR. Hemoglobin was adsorbed by three adsorbents - pristine peanut shells, crosslinked peanut shells and RG19 modified peanut shells, the results indicated that at 25℃and pH 7.0, the adsorption equilibrium of hemoglobin was carried out after 24hour,and the maximum adsorption capability were 134.9mg·g-1, 109.2mg·g-1 and 283.2mg·g-1, respectively. The adsorption data of pristine peanut shells and crosslinked peanut shells were in agreement with the Langmuir model,but the RG19 modified peanut shells was not. The results indicated that the eluantion effect of 0.5 mol·L-1 NaSCN(pH=10.0,50% acetone)was the best,and eluantion rate was 78.6%. In the best condition, the seperation and purification of femoglobin from the cattle blood samples were achived, and the hemoglobin was enriched 9.4-fold in a single step.2. An absorbent was prepared from peanut shells by the modification with RG19.The dosage of RG19, reaction time and NaCl concentration were tested with orthogonal design,the results indicated that the dosage of RG19 was key factor, reaction time and NaCl concentration were general factors, and the level of three factors were 500 mg, 4 hour and 0.5 mol·L-1 respectively. The load quantity of RG19 was 114 mg·g-1 with the standard curve method. Lysozyme was adsorbed by three adsorbents - pristine peanut shells, crosslinked peanut shells and RG19 modified peanut shells, the results indicated that at 25℃and pH 7.4, the adsorption equilibrium of lysozyme was carried out after 3 hour, and the maximum adsorption capability were 59.2 mg·g-1, 23.6 mg·g-1and 149.6mg·g-1, respectively. The adsorption data of three adsorbents were in agreement with the Langmuir model. The results indicated that the eluantion effect of 0.7 mol·L-1 NaSCN was the best,and eluantion rate was 97.4%. In the best conditions, the seperation and purification of lysozyme from egg white were achived.The lysozyme was purified 31.0-fold in a single step with a recovery 64.2 %,and the vigor retention rate of lysozyme was 96.4 %.3. A novel biosorbent from peanut shells was prepared with epichlorohydrin as cross-linking reagent and with ethylenediamine as grafting reagent. 10mL ethylenediamine, 100mL water and 1.0 g NaCO3, were mixed controlling reaction temperature at 65℃, mixing time for 2 h, then filtering, waterwashing and drying. The characterization of the modified peanut shells was obtained using FTIR and XPS. The adsorption behavior for the two proteins(hemoglobin and lysozyme) had been studied. The results indicated that at 25℃and pH 7.0, the adsorption equilibrium of hemoglobin was carried out after 24 hour, and the maximum adsorption capability was 364.8 mg·g-1,and at 25℃and pH 7.4, the adsorption equilibrium of lysozyme was carried out after 5 hour, and the maximum adsorption capability was 34.9 mg·g-1. The adsorption capability of hemoglobin was better than that of lysozyme. The adsorption data for lysozyme was in agreement with the Langmuir model, but the adsorption data for hemoglobin was not. The results indicated that for hemoglobin the eluantion effect of 0.5 mol·L-1 NaSCN(pH=10.0,50% acetone)was the best, and eluantion rate was 82.5%,but for lysozyme, the eluantion effect of 0.5 mol·L-1 NaSCN was the best, and eluantion rate was 98.7 %. In the optimizing condition,the seperation and purification of hemoglobin from the cattle blood samples were achived, and the hemoglobin was enriched 12.7-fold in a single step.4. The adsorption behavior of three bioadsorbents- pristine peanut shells, crosslinked peanut shells and RG19 modified peanut shells for BSA was investigated. the results indicated that the adsorption capability of the pristine peanut shells for BSA was the best, at 25℃and pH 5.0, the adsorption equilibrium of BSA was carried out after 15 hour, and the maximum adsorption capability was 303.6mg·g-1 .The adsorption data of the pristine peanut shells was in agreement with the Freundlich equation more than the Langmuir equation. The results indicated that 0.5 mol·L-1 imidazole was good for the eluantion. |
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