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A more general mathematical analysis of the kinetics of polycondensation-depolycondensation reactions is given in the article. Three different types of reactions are considered, namely, (1) reactions between molecules AB and AB, (2) reactions between molecules AA and BB, (3) reactions between molecules AA and BC. One of the condensation products is assumed (without loss of generality) to be water.For reactions of the first type, [p_n], the number of molecules of the n-mer (AB)_n, obeys the following Flory... A more general mathematical analysis of the kinetics of polycondensation-depolycondensation reactions is given in the article. Three different types of reactions are considered, namely, (1) reactions between molecules AB and AB, (2) reactions between molecules AA and BB, (3) reactions between molecules AA and BC. One of the condensation products is assumed (without loss of generality) to be water.For reactions of the first type, [p_n], the number of molecules of the n-mer (AB)_n, obeys the following Flory distribution: [p_n]=N_0p~(n-1)(1-p)~2 where N_0 denotes the total number of AB segments (including the unreacted monomers). and p, as defined by is a measure of the degree of condensation. It is shown that p is the solution of the following differential equation: dp/dt=k/2N_0(1-p)~2-k_(-1)p[H_2O] where K and k_(-1) are velocity constants of condensation and hydrolysis respectively, and [H_2O] denotes the number of water molecules. Three special cases are discussed.For reactions of the second type, three different types of condensation products are possible besides water; they obey the following distributions: [p_(2n)]=2N′_0r~(n-1)p~(2n-1)(1-p)(1-rp) [p′_(2n-1)]=N′_0r~(n-1)p~(2n-2)(1-p)~2 [p″_(2n-1)]=N′_0r~(n-2)p~(2n-2)(1-rp)~2 where N′_0 and N″_0 denote the total number of segments AA and BB respectively, r denotes the ratio N′_0/N″_0, and p, as defined by is the solution of the following differential equation: dp/dt=kn′_0/r(1-p)(1-rp)-k_(-1)P[H_2O]For reactions of the third type, six different types of condensation products are possible besides water; they obey the following distributions: [P′_(2n)]=NP~(n-1)q~n(1-p/2-q/2)(1-p) [p″_(2n)]=Np~nq~(n-1)(1-p/2-q/2_(?))(1-q) [p_(2n-1)=Np~(n-1)q~(n-1)(1-p/2-q/2)~2 [p′_(2n-1)]=N/4p~(n-2)q~n(1-p)~2 [p″_(2n-1)]=N/4p~nq~(n-2)(1-p)~2 [p′″_(2n-n)]=∈(n)N/4p~(n-1)q~(n-1)(1-p)(1-q),where N denotes either the total number of segments AA or that of BC, while p and q, as defined by satisfy the following set of differential equations: dp/dt=k′N/2(1-p)(2-p-q)-k′_(-1)p[H_O] dq/dt=k″N/2(1-q)(2-p-q)-k″_(-1)q[H_2O] 本文討論AB型,AA和BB型以及AA和BC型分子间的缩聚-裂解反應,由動力学方程出發,得到这三种类型反應过程中高聚分子的分佈情况,并求得几种不同反應條件下的缩聚度p和q是何种時间的函数,利用它们和实验数值比較,可以求得縮聚反應速度常数K和水解反應速度常数k_(-1),并在AA和BC型分子间的反應中,可以求得K'和K″的此值,藉以比较官能團B和C的活潑度。还討論了三种平均分子量的表示式、数值以及它们相互的比值,後者僅在没有水解作用的情况下,才和Flory的结果相同。 1.The principal reactions of methylcyclohexane,methylcyclopentane and heptane on platinum-fluorine-alumina catalyst of various platinum and hydrogen fluoride contents(Pt,0~1%;HF,0~5%)have been investigated under fixed reaction conditions:temperature,472℃,pressure,20 atm.,LHSV,3,H_2:feed (mol.ratio),6:1.The main results of present investigation are found to be in good agreement with the reaction machanism and the dual function of“houdri- forming” catalyst suggested by Mills and Heinemann.Platinum-fluorine- alumina... 1.The principal reactions of methylcyclohexane,methylcyclopentane and heptane on platinum-fluorine-alumina catalyst of various platinum and hydrogen fluoride contents(Pt,0~1%;HF,0~5%)have been investigated under fixed reaction conditions:temperature,472℃,pressure,20 atm.,LHSV,3,H_2:feed (mol.ratio),6:1.The main results of present investigation are found to be in good agreement with the reaction machanism and the dual function of“houdri- forming” catalyst suggested by Mills and Heinemann.Platinum-fluorine- alumina catalyst consists of two important kinds of active sites,i.e.the dehy- drogenation(or metal)site and the isomerization(or acid)site;the former is derived from platinum and the latter from hydrogen fluoride.Dehydroisomeri- zation of methylcyclopentane and isomerization of n-heptane can proceed effec- tively only upon the dual site catalyst. 2.With platinum content fixed at 0.3%,the following results for the effect of hydrogen fluoride on the reactions of methylcyclopentane and n-heptane are obtained:for HF content below 1%,benzene yield of methylcyclopentane increases by increasing hydrogen fluoride content,for HF content greater than 1%,no further appreciable influence is observed.Isomerization of n-heptane is easier than dehydroisomerization of methylcyclopentane,so that catalyst of 0.2% HF is very efficient for isomerization of n-heptane.The major effect of hydrogen fluoride in excess of 0.2% is to accelerate hydrocracking reaction and thereby decrease liquid yield remarkably.A short discussion for these experimental re- sults is presented with the use of the recent information published by Wēbb, which shows how the surface acid strength of alumina is influenced by vary- ing the content of hydrogen fluoride. 铂-氟氢酸-氧化铝催化剂具有两种主要的活性中心;一种是由铂产生的脱氢中心,一种是由氟氢酸产生的异构化中心.甲基环己烷、甲基环戊烷、正庚烷在铂-氟氢酸-氧化铝催化剂上的主要反应结果符合于 Mills-Heinemann 提出的反应机理.催化剂的平均孔径随氟氢酸的含量增加而变大,孔径变大可能是正庚烷的加氢裂化反应随氟氢酸含量增加而显著加速的原因. ? ycTaHoBeHe HapaBeH paBT TexHk ypoBpbIBHbIx paoTHa oTeecTBeHHbIx pyHbIx Kapbepax oHo cxoTbc TpeoBaHpaBT HapoHoo xocTBa c yeToM obIToB poBocTBaKapbepoB, ocoeHHocT ppoHbIx pecypcoB oeHbIx cKoaeMbIxTexHecKoo paBT apyeHbIx kapepoB. 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