利用三相相間轉移觸媒合成多苯氧基磷氮環化合物之鹼量影響

Base Effect of Synthesizing Partially Substituted- (phenoxy) cyclotriphosphazene by Triphase Catalysis

李忠錂(Chang-Lin Lee)

指導教授 ： 吳和生

元智大學/工程學院/化學工程與材料科學學系/碩士(1998年)

摘要

相間轉移觸媒催化技術應用於水油兩相之有機合成反應已十分普及，惟其存在有產物分離及觸媒回收之因素，本研究以固定化相間轉移觸媒分別在批次(bach)和全回流(total recycle)固定床反應器中進行六氯環三偶磷氮(hexachlorocyclotriphosphazene)和酚(phenol)的取代反應，將分別探討不同鹼量、溫度、六氯環三偶磷氮用量、觸媒種類及用量等變因，且求得相關之反應動力學常數。
由實驗研究結果得知其結論為：
（1） 隨著溫度、鹼量、觸媒用量增加，虛擬一次反應速率常數增加。
（2） 由溫度與活化能關係中得知，當氫氧化鈉量在0.9Ｍ時其活化能下降，其受到油水不連續相之擴散阻力影響而造成。觸媒顆粒愈小，活化能越低，受顆粒擴散影響愈明顯。
（3） 在六氯環三偶磷氮合成多苯氧基磷氮環化合物取代反應中，隨著鹼量增加磷氮環化合物產物隨之取代數增加，在三小時內僅在一、二取代有完整反應，因受到顆粒質傳影響，使反應緩慢進行。
(4) 由批式反應器模擬放大為全回流式固定床，無論使用巨孔隙、
微孔隙及不同環取代其調整流速反應均維持一定產率，而在不
同回流比之影響可明顯看出反應隨者回流比不同有不同變化。

關鍵字

相間轉移觸媒催化技術 ； 磷氮環化合物 ； 三相觸媒催化技術 ； 顆粒擴散影響 ； 環取代數 ； 離子交換 ； 批式反應 ； 固定座反應

並列摘要

Phase-transfer catalysis is usually applied for synthesizing an organic compound, in the organic-aqueous phases. However, the separation and rease of the catalyst in the reaction system need to encounter. In this study, the substitution reaction of hexachlorocyclotriphosphazene and phenol was investigated using polymer supported ammonium salt in the batch reactor and total recycle fixed bed reactor. The concentration of base, reactants and catalyst, temperature and the kinds of catalyst were studied to obtain the optimum reaction condition. The relative reaction-rate constants and activation eneries were also calculated.
According to the experimental result, same conclusions are listed as following:
(1) psendo-first-order reaction-rate constant was increased with increasing
temperature, the concentrations of base and phase-transfer catalyst.
(2) The arrherius activation energy for this substitution reaction had a minimum
value, the particle diffusion resistance of reactant from bulk solution to
active site was main an factor in increasing apparent reactivity. The
Arrherius activition energy was decreased by decreasing the particle size of
triphase catalyst. It is demonstrated that the particle diffusion is an
important factor in enhancing reaction rate.
(3) The substitution degree of hexachlorotricyclophosphazene reacting phenol
was increased with increasing base concentration. However, the
substitution procedures for the first and the second substitution products
were complete. The finding denstrated the particle diffusion can not
be neglected in this reaction system.
(4) The reaction rate of phosphazene replaced reaction in batch reactor was
rapid than that in total recycle fixed-bed reaction. The product yield of the
first to the third substitution reaction was decreased by decreaing recycle
ratio of effluent to recycle stream.

並列關鍵字

Phase transfer catalysis ； phosphazene ； tri-phase catalysis ； interparticle diffusion ； Number of ring-substitution ； ion-exchange ； batch reaction ； packing-bed reaction

參考文獻

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