固相烧结法制备金属陶瓷及其在催化和分离领域中的应用研究

发布时间：2018-05-09 01:06

  本文选题：金属陶瓷 + 酶固定化　； 参考：《天津大学》2015年博士论文

【摘要】：本文借助陶瓷高稳定性,高机械强度等优点,通过掺杂各类金属,烧结制得高活性功能化金属陶瓷(MCP),分别应用于生物分子螯合吸附后的催化与纯化,臭氧催化氧化处理生活污水,以及重金属离子的分离及再利用等多类体系,具体包括:以MCP为载体高效固定化淀粉酶、脂肪酶等工业酶制剂并开展生物催化应用;以MCP为基质经螯合吸附,实现酪蛋白磷酸肽(CPPs)的富集纯化制备;以MCP为催化剂催化臭氧快速深度氧化难降解有机物,实现船舶生活污水的高效处理;去除重金属污染物,通过制备MCP实现重金属离子的再利用,主要结果如下:1.以掺杂铜的金属陶瓷作为淀粉酶的固定化载体(Cu-MCP),通过Cu2+对淀粉酶的特异性螯合作用,将淀粉酶固载于Cu-MCP表面,制得酶活收率为54.5%的固定化淀粉酶(Cu-MCP-amylase);Cu-MCP-amylase的最适催化温度为70oC,最适pH为7.0,最适应用范围和热稳定性,均较游离酶有所提高;Cu-MCPamylase在柱式反应器内具有高效催化淀粉水解制备还原糖的能力,当填充高度为18.0cm,停留时间为1.61min时,淀粉底物可获得81.94%的转化率。2.以掺杂镍的金属陶瓷作为脂肪酶的固定化载体(Ni-MCP),利用镍离子对脂肪酶的特异性螯合与激活作用,制得酶活收率为216%的固定化脂肪酶(NiMCP-lipase);Ni-MCP-lipase的最适催化温度为40oC,最适pH为6.0,贮存稳定性和热稳定性较游离酶均明显提高;Ni-MCP对脂肪酶展现出良好的生物亲和性和激活作用,在Ni-MCP-lipase加入量为3.0g,反应温度为35oC,酸醇比为2:1的15.0m L反应体系中,可以催化酸醇直接合成乙酸肉桂酯,并获得62.56%的收率,而游离酶几乎无催化此反应的能力。3.基于固定金属亲和层析技术,以掺杂钛的金属陶瓷(Ti-MCP)为富集材料,对酪蛋白酶解液经螯合吸附,分步洗脱等步骤高效富集制得酪蛋白磷酸肽(CPPs);当酪蛋白酶解物与金属陶瓷质量比为1:10时,1g金属陶瓷可以富集制备78mgCPPs,制备收率为78%,且Ti-MCP具有优异的稳定性,重复利用10次后,CPPs的制备收率仍超过75%;表明掺杂钛的金属陶瓷是一种具有较大比表面积,优异机械性能及高稳定性的陶瓷富集材料,可以高效重复纯化CPPs,具有传统制备方法所不具备的优势。4.以高稳定性金属陶瓷(Ni-MC,Ti-MC)为催化剂,可将臭氧催化分解为羟基自由基,深度氧化船舶生活污水中的难降解有机物,快速降低污水的COD指标:对于Ni-MC,在1小时内COD由600降低至222,COD去除率达到63%;对于Ti-MC,设计了电芬顿-臭氧催化氧化组合工艺快速处理生活污水,2h内两步法分别获得53.2%和51.7%的COD去除率,COD由1200降低至271,总体COD去除率为77.4%。且Ti-MC重复使用10次后,几乎无金属离子泄露,COD去除率仅从51.7%降低至48.7%;表明掺杂Ni或Ti的金属陶瓷是一种催化活性高,性质稳定的催化剂,可以高效、重复用于生活污水的快速、深度处理,较传统臭氧催化氧化过程中的催化剂具有特殊优势。5.壳聚糖和三聚磷酸钠反应生成的壳聚糖纳米颗粒对溶液中的重金属同时具有吸附和包埋作用,可将工业上常见的铬、镍等重金属污染物从水体中去除:Ni2+的去除率为99.4%,Cr3+的去除率为97.5%,Cr2O72-的去除率为81.2%;将壳聚糖分离的重金属污染物与陶瓷基质混烧,制得金属陶瓷[Ni-CP,Cr(III)-CP,Cr(VI)-CP];Ni-CP通过激活、螯合可实现脂肪酶的固载,酶活收率为164%;Cr(III)-CP和Cr(VI)-CP可以催化葡萄糖转化为重要平台化合物5-羟甲基糠醛,转化率85%,收率60%。上述工艺不仅能将重金属离子从水体中分离,而且还可将重金属离子固定于陶瓷内,制得金属陶瓷的同时,避免再次泄露,实现重金属污染物的资源化利用。
[Abstract]:In this paper, with the advantages of high stability and high mechanical strength of ceramics, high active functionalized metallized cermet (MCP) is prepared by doping various kinds of metals. It is applied to the catalysis and purification of bio molecular chelating adsorption, the treatment of domestic sewage by ozonation and oxidation, as well as the separation and reuse of heavy gold ions, including: MCP was used as the carrier to immobilize amylase, lipase and other industrial enzyme preparations and to carry out biocatalysis. The enrichment and purification of casein phosphopeptide (CPPs) was achieved by chelating adsorption with MCP as the matrix. The rapid and deep oxidation of refractory organic compounds with MCP as catalyst was used to achieve high efficiency treatment of marine sewage, and the heavy gold was removed. By preparing MCP for the reuse of heavy metal ions, the main results are as follows: 1. with copper doped cermet as a immobilized carrier of amylase (Cu-MCP), the amylase is immobilized on the surface of Cu-MCP through the specific chelation of Cu2+ to the amylase, and the immobilized amylase (Cu-MCP-amylase), which has the yield of 54.5%, is prepared, and Cu is prepared. The optimum catalytic temperature of -MCP-amylase is 70oC, the optimum pH is 7, the optimum application range and the thermal stability are higher than that of the free enzyme. Cu-MCPamylase has the ability to catalyze the hydrolysis of starch to prepare reducing sugar efficiently in the column reactor. When the filling height is 18.0cm and the residence time is 1.61min, the starch substrate can obtain 81.94% conversion of.2. A immobilized lipase immobilized carrier (Ni-MCP) with nickel doped cermets was used to produce a immobilized lipase (NiMCP-lipase) with an enzyme activity of 216%, using the specific chelation and activation of nickel ions to lipase. The optimum catalytic temperature of Ni-MCP-lipase was 40oC, the optimum pH was 6, and the storage stability and thermal stability were better than that of the free enzyme. The Ni-MCP showed good biological affinity and activation to lipase. In the Ni-MCP-lipase addition of 3.0g, the reaction temperature was 35oC, the acid alcohol ratio of 2:1 to 15.0m L reaction system could catalyze the direct synthesis of cinnamyl acetate with acid alcohol, and the yield of 62.56% was obtained, while the free enzyme had almost no ability to catalyze this reaction.3. based on solid. Metal ceramic (Ti-MCP) doped with titanium was used as the enrichment material, and the casein phosphopeptide (CPPs) was enriched by chelating adsorption and stepwise elution. When the quality ratio of casepase and cermets was 1:10, 78mgCPPs was prepared by 1g cermet, and the yield was 78%. Ti-MCP has excellent stability. After repeated use of 10 times, the yield of CPPs is still more than 75%. It shows that the cermet doped with titanium is a ceramic enrichment material with large specific surface area, excellent mechanical properties and high stability. It can be highly efficient to repeat the purification of CPPs with high stability gold. Ni-MC (Ti-MC) is a catalyst, which can catalyze the decomposition of ozone into hydroxyl radical, oxidize the refractory organic matter in marine sewage and reduce the COD index of sewage quickly. For Ni-MC, COD is reduced from 600 to 222 in 1 hours, and COD removal rate reaches 63%. For Ti-MC, the combination process of electric Fenton ozone catalytic oxidation is designed quickly. The removal rate of COD in 2H two step method was 53.2% and 51.7% respectively, and COD was reduced from 1200 to 271. The total COD removal rate was 77.4%. and Ti-MC was repeated for 10 times. There was almost no metal ion leakage, and the COD removal rate was only from 51.7% to 48.7%. It showed that the metal ceramics doped with Ni or Ti was a catalyst with high catalytic activity and stable properties. It can be used efficiently and repeatedly for the rapid and deep treatment of domestic sewage. Compared with the traditional ozone catalytic oxidation process, the catalyst has special advantages, such as.5. chitosan and sodium tripolyphosphate, which can also adsorb and bury the heavy metals in the solution. The removal rate of Ni2+ was 99.4%, the removal rate of Cr3+ was 97.5%, and the removal rate of Cr2O72- was 81.2%. The metal ceramic [Ni-CP, Cr (III) -CP, Cr (VI) -CP] were prepared by mixing the heavy metal pollutants separated by chitosan and ceramic matrix, and the lipase was immobilized by chelating, and the yield of the enzyme was 164%. And Cr (VI) -CP can catalyze the conversion of glucose into an important platform compound, 5- hydroxymethyl furfural, the conversion rate is 85%. The yield 60%. can not only separate heavy metal ions from the water, but also immobilized the heavy metal ions in the ceramics. At the same time, the metal ceramics can be made to avoid the re leakage and realize the resources of heavy metal pollutants. Use.

【学位授予单位】：天津大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TQ174.1
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本文编号：1863875