钙镍基单/双金属催化甲壳素热解特性研究

STUDY ON CHITIN PYROLYSIS CHARACTERISTICS BY CALCIUM-NICKEL BASED MONO/BIMATALLIC CATALYSTS

以甲壳素为生物质模拟物,采用热重-质谱联用技术研究钙基单/双金属催化热解特性。相比于Ni单金属催化剂,NiFe双金属催化剂的比表面积、平均孔径和孔体积分别提高了309.01%、11.61%和100%,有利于改善热解气与催化剂的接触效果。催化甲壳素热解从易到难排序为Ni、Fe、FeCu=CuNi、Cu、FeNi;催化制氢效果从强到弱排序为Ni>CuNi>FeNi>Cu>FeCu>Fe。Ni单金属有最大产氢峰值,为0.5943 mmol/(g·min),过高温度不利于催化剂发挥活性。Ni和Cu单金属催化剂可增大NH3的析出峰值,分别增大了94.17%和72.96%;提高热解温度有利于NH3的析出,建议催化热解温度不超过600℃。研究探明钙基Ni、Cu、Fe及其双金属催化剂催化生物质(甲壳素)热解特性,并揭示NH3在热解过程中的释放特性。

In this paper,chitin was used as a biomass simulant,and thermogravimetric mass spectrometry was applied to study the hydrogen and NH3 release characteristics of calcium-based mono-and bimetallic catalytic pyrolysis.When Fe was added,the specific surface area,average pore diameter,and pore volume were 309.01%,11.61%,and 100%higher than that of the Ni monometallic catalyst,respectively,which is beneficial for improving the contact effect between the syngas and catalysts.In addition,the order of catalytic pyrolysis from easy to difficult is Ni、Fe、FeCu and CuNi、Cu、FeNi,meanwhile,the sequence of catalytic hydrogen production improvement is Ni、CuNi、FeNi、Cu、FeCu、Fe.The catalytic hydrogen production of Ni is the best,and the peak value is 0.5943 mmol/(g·min).Should be noted that,high temperature is not conducive to the activity of Ni-based catalysts.Ni and Cu mono-metallic catalysts increases the peak of NH3 by 94.17%and 72.96%,respectively.Further,the raising of pyrolysis temperature is beneficial for the release of NH3.It is suggested that the catalytic pyrolysis temperature should not exceed 600℃to control the release of NH3.This study can provide theoretical guidance for the preparation of high-grade clean syngas through the catalytic pyrolysis of biomass.This study investigates the pyrolysis characteristics of biomass(chitin)catalyzed by calcium-based Ni,Cu,Fe and their bimetallic catalysts.Furthermore,the release characteristics of NH3 during the pyrolysis process is obtained.