13X分子筛涂层制备及用于脱除丹参中铅和镉

Preparation of 13X Zeolite Film and Its Application for Removal of Lead and Cadmium in Salvia Miltiorrhiza

摘要:

运用预涂溶胶、低温干燥、合成液中晶化生长的方法在α-Al2O3陶瓷管表面制备了13X分子筛涂层，优化得到了摩尔组成为n(Al2O3):n(SiO2):n(Na2O):n(H2O)=1:3.5:7.88:630的合成液，考察了制备条件对13X分子筛涂层的影响。结果表明：只有预涂溶胶的α-Al2O3陶瓷管表面可得到连续均匀的分子筛涂层，且采用预涂溶胶比凝胶更有利于制得连续的13X分子筛涂层。当溶胶干燥温度为35~45℃，干燥时间为12~18h时，XRD、SEM测试结果显示：陶瓷管表面可以得到结晶较好的连续涂层。将上述13X分子筛涂层用于丹参提取液中铅和镉的脱除，脱除率分别可达86.7%和44.2%，经过净化后的丹参提取液的含固量、丹酚酸B和迷迭香酸保留率分别为99.6%、96.8%、99.3%，与13X分子筛颗粒相比无明显变化。丹参提取液在处理前后的高效液相指纹图谱相似度接近100%。

Abstract:

13X zeolite films on α-Al2O3 ceramic tube were prepared by using the method of pre-coating sol, then drying in lower temperature and crystallizing in synthetic solution. The optimal molar composition of synthetic solution was n(Al2O3):n(SiO2):n(Na2O):n(H2O)=1:3.5:7.88:630, and the influences of preparation conditions on formation of 13X zeolite films were investigated. The results showed that continuous and uniform films were observed on α-Al2O3 ceramic tube only with pre-coating sol. It was easier to form continuous films with pre-coating sol than with pre-coating gel. Under the condition that drying temperature and drying time of the pre-coating sol were within 35~45℃ and within 12~18h respectively, continuous 13X zeolite films were easier grown on the surface of ceramic tube judging from XRD patterns and SEM images. By application of the 13X zeolite film to remove lead and cadmium in Salvia miltiorrhiza extract, the removal ratios of lead and cadmium were 86.7% and 44.2% respectively. During the removal process, there was nearly no significant change of active ingredients in Salvia miltiorrhiza extract compared with 13X zeolite particles. The retention rates of solid content, Salvia miltiorrhizanolic Acid B and Rosmarinci Acid were 99.6%, 96.8% and 99.3% respectively. In addition, HPLC fingerprint similarity of Salvia miltiorrhiza extract approached 100% before and after lead and cadmium removing process.