Xia Hai-Feng, Lin Dong-Qiang, Yao Shan-Jing
Department of Chemical and Biochemical Engineering, Zhejiang University, 310027 Hangzhou, China.
J Chromatogr A. 2007 Mar 23;1145(1-2):58-66. doi: 10.1016/j.chroma.2006.12.098. Epub 2007 Jan 10.
New adsorbents Q HyperZ and CM HyperZ composed of hydrogel-filled porous zirconium oxide particles were evaluated for expanded bed adsorption applications in the present work. The HyperZ adsorbents have wet density of 3.16 g ml(-1), particle size of 44.5-100.8 microm and average sphere diameter of 67 microm. The bed expansion as the function of flow velocity and fluid viscosity was measured and correlated with Richardson-Zaki equation. The suitable expansion factor was considered less than 2.5, while the corresponding flow velocity was about 450 cmh(-1). Liquid mixing in the bed was determined to evaluate the stability of expanded bed. The Bodenstein numbers tested were higher than 40 and the axial mixing coefficients (D(ax)) were between 0.5 and 9.7x10(-6)m(2)s(-1), which demonstrated that a stable expanded bed could be formed under suitable operation conditions. Bovine serum albumin (BSA) and lysozyme were used as model proteins to estimate the adsorption capacities of Q and CM HyperZ, respectively. The maximum equilibrium adsorption of Q and CM HyperZ could reach 45.7 and 27.2 mg g(-1) drained adsorbents, respectively. It was found that yeast cells had little influence on the adsorption capacities of the two adsorbents tested. The dynamic adsorption capacity of BSA at 10% breakthrough with Q HyperZ was 35.9 mg g(-1) drained adsorbent at flow velocity of 100 cm h(-1) for packed bed adsorption. The values for expanded bed adsorption were 34.4 mg g(-1) drained adsorbent at flow velocity of 200 cm h(-1), 33.6 mg g(-1) drained adsorbent at 300 cm h(-1) and 31.7 mg g(-1) drained adsorbent 400 cm h(-1). The results demonstrated that Q HyperZ and CM HyperZ are suitable for expanded bed adsorption of biomolecules.
在本研究中，对由填充水凝胶的多孔氧化锆颗粒组成的新型吸附剂Q HyperZ和CM HyperZ进行了膨胀床吸附应用评估。HyperZ吸附剂的湿密度为3.16 g ml(-1)，粒径为44.5 - 100.8微米，平均球径为67微米。测量了床层膨胀随流速和流体粘度的变化，并与Richardson-Zaki方程相关联。合适的膨胀因子被认为小于2.5，而相应的流速约为450 cmh(-1)。测定了床层中的液体混合情况以评估膨胀床的稳定性。测试的 Bodenstein数高于40，轴向混合系数（D(ax)）在0.5至9.7×10(-6)m(2)s(-1)之间，这表明在合适的操作条件下可以形成稳定的膨胀床。分别使用牛血清白蛋白（BSA）和溶菌酶作为模型蛋白来评估Q HyperZ和CM HyperZ的吸附容量。Q HyperZ和CM HyperZ的最大平衡吸附量分别可达45.7和27.2 mg g(-1)（沥干吸附剂）。发现酵母细胞对所测试的两种吸附剂的吸附容量影响很小。在填充床吸附中，Q HyperZ在10%穿透时对BSA的动态吸附容量在流速为100 cm h(-1)时为35.9 mg g(-1)（沥干吸附剂）。在膨胀床吸附中，在流速为200 cm h(-1)时为34.4 mg g(-1)（沥干吸附剂），在300 cm h(-1)时为33.6 mg g(-1)（沥干吸附剂），在400 cm h(-1)时为31.7 mg g(-1)（沥干吸附剂）。结果表明，Q HyperZ和CM HyperZ适用于生物分子的膨胀床吸附。
