CPC-B/CMC有机复合膨润土凝胶的制备及表征

Preparation and Characterization of CPC-B/CMC Organic Compound Bentonite Gel

以辽宁黑山钠基膨润土为原料,采用氯代十六烷基吡啶(CPC)和羧甲基纤维素钠(CMC)为改性剂对膨润土(B)进行改性处理,制得复合凝胶吸附剂(CMC/CPC-B)。采用单因素及响应面分析法对制备工艺进行了优化,并利用SEM和XRD测试手段进行结构表征分析。结果表明,CMC/CPC-B的最佳制备条件为:CMC与CPC-B投加量(质量)比为4∶1,p H值为4,温度为60℃,交联剂(Al Cl3)浓度为0.1 mol/L,制备的CMC/CPC-B吸附苯酚量最高,可达2.8329 mg/g。因素影响强弱顺序为p H值>温度>CPC-B投加量,交联剂浓度影响不显著。因素交互影响较小,只有p H值与配比交互影响显著,其它交互项影响均不显著。CPC-B/CMC结构上与原土及单改性土明显不同,由片层结构变为网状交联的凝胶结构;CPC-B与CPC-B/CMC的X射线衍射首峰与原土相比向小角度方向偏移,层间距明显增加,CPC-B/CMC的衍射峰位于原土与CPC-B衍射峰之间,经交联反应后层间距被交联结构占据而减小。

Using Liaoning Montenegro sodium bentonite as raw materials, cetylpyridinium chloride（CPC） and sodium carboxymethyl cellulose（CMC） as a modifier of the bentonite（B） modification treatment, produce composite gel adsorbents（CMC / CPC-B）. Single factor and response surface analysis method was used to optimize the preparation process, and by using testing means SEM and XRD for structural characterization analysis. The results showed that, the best preparation conditions were： When the CMC is 4 g, the optimal dosage of CPC-B is 1 g, p H=4, temperature is 60 ℃, cross linking agent（Al Cl3） concentration is 0.1 mol/L, CMC/CPC-B adsorbed phenol prepared by this process was the highest, up to 2.8329 mg/g. The order of the factors affecting the strength is： p H temperature dosage of CPC-B. Crosslinking agent concentration had no significant effect. CPC-B/CMC structure was significantly different from that of the original soil and the modified soil, lamellar structure becomes a network cross-linked gel structure; XRD diffraction peak of CPC-B and CPC-B/CMC two were offset to small angular direction compared with the original soil. Layer spacing also increased significantly, the diffraction peak shifts to a large angle and between the original soil and CPC-B diffraction peaks, layer spacing is reduced by cross linked structure.