Using chitosan as raw material, liquid paraffin as dispersant, formaldehyde as pre-crosslinking agent and epichlorohydrin as crosslinking agent, crosslinked chitosan microspheres were prepared by reversed-phase suspension method. The adsorption properties of crosslinked chitosan microspheres on aromatics carboxy compounds in water were studied. The results showed that it had fast adsorption rate and large adsorption capacity, the saturated adsorption capacity of crosslinked chitosan microspheres for 2-hydroxy-3-naphthoic acid, α-naphthoic acid and benzoic acid were 702. 0 mg·g-1, 320. 1 mg·g-1, 176. 3 mg·g-1at the p H value of 3. 5and 288 K, respectively. The adsorption process conformed to the Lagergren-second-order kinetic equation, and the adsorption isotherm model conformed to the Langmuir isotherm adsorption equation, which was mainly monolayer adsorption. The adsorption process was a spontaneous, exothermic and entropic reduction process with physical adsorption and chemical action. The crosslinked chitosan microspheres had good recycling ability. After 8 cycles of regeneration, the adsorption capacity could still be stabilized above 97％.%以壳聚糖为原料、液体石蜡为分散剂、甲醛为预交联剂、环氧氯丙烷为交联剂,采用反相悬浮法制备交联壳聚糖微球,并研究其对水中2-羟基-3-萘甲酸、α-萘甲酸、苯甲酸3种芳香族羧基化合物的吸附性能.结果表明:1)在弱酸性介质(pH=3～4)中,交联壳聚糖微球对上述3种芳香族羧基化合物的吸附速度快、吸附容量大,当pH=3. 5,温度288 K条件下,其饱和吸附容量分别为702. 0 mg·g-1,320. 1 mg·g-1,176. 3 mg·g-1. 2)其吸附过程符合Lagergren二级动力学方程,吸附反应较容易发生;吸附等温模型符合Langmuir等温吸附方程,该吸附过程主要为单分子层吸附,吸附过程是一个以物理吸附为主,同时伴有化学作用的自发、放热、熵减过程. 3)交联壳聚糖微球具有较好的循环再生能力,经过8次循环再生过程,其吸附容量仍能稳定在97％以上.
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