摘要
以活性炭为载体,磷钨酸(HPW)为活性组分,通过浸渍法制备活性炭负载磷钨酸(HPW/C)催化剂,研究其对聚酰胺6(PA6)水解反应的影响。通过FT-IR、XRD、BET、GCMS和UV等对催化剂和水解产物进行表征分析。结果表明,当HPW负载量小于55%时,能均匀分散在活性炭的表面和孔隙;固相剩余物为未完全分解的PA6;液相产物的主要成分为己内酰胺(CPL); HPW/C催化PA6水解的优化条件为:HPW负载量为45%、催化剂质量分数为10%、反应温度为260℃、反应时间为1 h,此时,PA6降解率和CPL产率可分别达83%与56%。
HPW/C,an activated carbon supported phosphotungstic acid catalyst,is prepared by impregnation method with activated carbon as support and phosphotungstic acid( HPW) as active component. Its effects on the hydrolysis reaction of polyamide 6( PA6) are also studied.The catalyst and hydrolysis products are characterized by test methods like FT-IR,XRD,BET,GCMS and UV.It is shown that HPW disperses highly on the surface and in the pores of activated carbon when the loading amount of HPW is lower than 55%; the solid phase residue contains incompletely decomposed PA6 and the main component of the liquid phase product is ε-caprolactam( CPL).The optimum conditions of hydrolysis reaction are proved as follows: the loading amount of HPW is 45%,the dosage of the catalyst is 10%,the reaction temperature and time are 260℃ and 1 hour,respectively.Under optimum conditions,PA6 degradation rate and CPL yield can reach 83% and 56% respectively.
引文
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