Metal Ceramic Preparation Via Solid Phase Sintering Method And Its Application In Catalysis And Separation

In this work, considering the excellent stability and mechanical strength of the ceramic, the metal ceramic(MCP) was prepared by doping of metal compound and turned into practial material with high activity. The metal ceramic was applied in many kinds of fields, such as chelation affinity of biomolecules for catalysis and purification, catalytic ozonation of sewage, separation and recycle of heavy metal pollutions. That is immobilization of amylase and lipase which are commonly used in industry on MCP, purification of casein phosphopeptides(CPPs) from casein enzymatic hydrolysis solution, applicaition in catalytic ozonation of ship sewage for rapid disposition by MCP, disposition and recycle of Cr, Ni heavy metal pollutant through preparation of MCP, and the main results were listed below:1. The metal ceramic doped with Cu(Cu-MCP) was used as carrier for amylase immobilization and the amylase immobilized on Cu-MCP through chelation of Cu2+ on MCP surface, then the Cu-MCP-amylase with 54.5% activity yield could be obtained. The optimal temperature of Cu-MCP-amylase was 70 oC and the optimal pH value was 7.0, moreover, the suitable application range and thermal stability were also improved compared with free amylase. Cu-MCP-amylase exhibited significant efficiency for reduced-sugar preparation through starch hydrolysis in column reactor. With 18.0cm column height packed by Cu-MCP-amylase, the.starch could obtain 81.94% conversion during 1.61 min.2. The metal ceramic doped with Ni(Ni-MCP) was used as carrier for lipase immobilization. Through the chelation and activation of Ni2+ on Ni-MCP surface, the immobilized lipase(Ni-MCP-lipase) could be obtained with activity yield of 216%. The optimal temperature of Ni-MCP-lipase was 40 oC and the optimal pH value was 6.0. Moreover, compared with free lipase, the storage stability and thermal stability of Ni-MCP-lipase were also improved. Ni-MCP exhibited excellent biocompatibility and activation to lipase. As the addition of Ni-MCP-lipase was 3.0g, the reaction temperature was 35 oC, the acid/alcohol ratio was 2:1 in 15.0m L reaction system, the Ni-MCP-lipase could catalyze the synthesis of cinnamyl acetate by cinnamyl alcohol and acetic acid, and 62.56% cinnamyl acetate yield could be obtained, while the free lipase had almost no catalytic capacity in the same conditions.3. According to immobilized metal ion affinity chromatography technology, the metal ceramic doped with Ti(Ti-MCP) was used for CPPs purification. CPPs was prepared through enzymolysis, adsorption, washing and enrichment processes. While the mass ratio of casein/Ti-MCP was 1:10, 1g metal ceramic could prepare 78 mg CPPs and the CPPs preparation yield was 78%. Moreover, the Ti-MCP exhibited significant stability. As the Ti-MCP was reused for 10 times, the CPPs preparation yield could also exceed 75%. Therefore, Ti-MCP was an enrichment material with large specific surface area, excellent mechanical strength and high stability, which could efficiently and steadily prepare CPPs, and these obvious advantages could not be found in traditional CPPs preparation process.4. Through application of metal ceramic catalyst(Ni-MC, Ti-MC) with high stability, the O3 could be decomposed into hydroxyl radicals. The hydroxyl radicals could decompose the refractory organic compounds in ship sewage and rapidly reduce the COD value. As for Ni-MC, the COD could decrease from 600 to 222 and the COD removal could reach 63% during 1h through catalytic ozonation process. As for Ti-MC, the Electro-Fenton and catalytic ozonation combination method for sewage disposition was established. The Eectro-Fenton process could supply 53.2% COD removal and catalytic ozonation could supply 51.7% COD removal. Then, the whole COD removal could reach 77.4% and the sewage COD could decrease from 1200 to 271. Moreover, as the Ti-MC was reused for 10 times, almost no Ti4+ leaked from TiMC and the COD removal just decreased from 51.7% to 48.7%. Thus, the metal ceramic(Ni-MC, Ti-MC) were ideal catalysts with high catalytic efficiency and excellent stability, which could be used efficiently and repeatly in rapid ship sewage disposition and deeply oxidation. Compared with traditional catalyst used in advanced oxidation, metal ceramic catalyst showed special advantages.5. Through application of chitosan nanoparticle formed via reaction of chitosan and TPP, the adsorption and entrapment of chitosan nanoparticle was combined and used to remove the common heavy metal pollutant(Ni, Cr) from water phase. Ni2+ removal could reach 99.4%, Cr3+ removal could reach 97.5% and Cr2O72- removal could reach 81.2%. Then the removed heavy metal pollutants were mixed with ceramic matrix and calcined to prepare metal ceramic [Ni-CP, Cr(III)-CP, Cr(VI)-CP]. The Ni-CP could be used in lipase immobilization through activation and chelation, and the lipase activity yield could reach 164%. Cr(III)-CP and Cr(VI)-CP could converse glucose into 5-hydroxymethylfurfural, which is an important platform chemical compound, and the glucose conversion could reach 85% and 5-HMF yield could reach 60%. Thus the process not only could remove the heavy metal pollutants from water phase, but also could immobilize the heavy metal ions in ceramic. The heavy metal ion leakage could be avoided and the heavy metal pollutant could be transformed into resource as the metal ceramic prepared.