Analysis and Regulation of Catalytic Reaction Network in 1,4-Butynediol by Reppe Method
Within a triphasic(gas-liquid-liquid)reactor equipped with 26 candle filters,various side reactions occur between formaldehyde and acetylene,resulting in complex by-products that can cause filter blockage and affect the long-term operation of the reactor.The composition of the blockage material in the 1,4-butynediol production reactor was qualitatively and quantitatively analyzed using techniques such as scanning electron microscopy(SEM),transmission electron microscopy(TEM),inductively coupled plasma optical emission spectrometry(ICP),gel permeation chromatography(GPC),pyrolysis-gas chromatography-mass spectrome-try(Py-GC-MS),and in-situ infrared spectroscopy(in-situ IR).The catalytic reaction network responsible for the the formation of blockage was investigated,and significant factors influencing the network were experimen-tally verified.The results revealed that the blockage consisted of inorganic matter(w=39.4%)and organic matter(w=60.6%).The inorganic matter comprised catalyst fragments and the organic matter constituted copolymers derived from acetylene and oxygen-containing intermediates.Compared to fresh catalyst,the cata-lyst particles within the blockage undergone changes in both its macroscopic morphology and microscopic com-position.The active component Cu2+ transformed into Cu0,accompanied by the depletion of other constituents and notably a significant loss of Bi.Polyacetylene resulted from self-polymerization of acetylene on Cu0.The oxygen-containing polymers were intermediates formed from the nucleophilic addition reaction between formal-dehyde and acetylene.Based on the analysis of the blockage composition and the evolution of Cu species,a pos-sible catalytic reaction network within the 1,4-butynediol production reactor was proposed,and was verified by industrial catalysts in conjunction with parameters such as pH values,the volume fraction of acetylene,and the volume fraction of formaldehyde.The above reaction network offers guidance for the synergistic regulation of activation and reaction processes.
国家科技期刊平台
NSTL
万方数据
