Cu-Ni掺杂多孔金属氧化物催化竹材的液化  

Catalytic Liquefaction of Bamboo by Cu-Ni Doped Porous Metal Oxide

作　　者：叶结旺[1,2] 蒋剑春 戴伟娣[2] 金贞福[1] 张晓春[1] Ye Jiewang;Jiang Jianchun;Dai Weidi;Jin Zhenfu;Zhang Xiaochun(National Engineering&Technology Research Center of Wood-Based Resources Comprehensive Utilization,Zhejiang Agriculture&Forestry University,Lin’an 311300;Institute of Chemical Industry of Forest Products, CAF, Nanjing 210042)

机构地区：[1]浙江农林大学国家木质资源综合利用中心,临安311300 [2]中国林业科学研究院林产化学工业研究所,南京210042

出　　处：《林业科学》2020年第4期143-149,共7页Scientia Silvae Sinicae

基　　金：国家自然科学基金项目(31530010);浙江农林大学科研发展基金项目(2019FR016)。

摘　　要：【目的】探究超临界甲醇介质中反应因素对Cu、Ni掺杂多孔金属氧化物(PMO)催化竹材液化产物的影响,以揭示活性组分在竹材液化过程的作用。【方法】以类水滑石为前驱体,通过共沉淀方法制备Cu、Ni掺杂的PMO催化剂,采用XRD、BET、SEM对催化剂进行表征。竹材液化在超临界甲醇介质中进行,液化产物采用GC-MS分析。通过单因素分析Cu/Ni比、催化剂用量、反应温度和反应时间对产物组成和分布的影响。【结果】XRD显示,Cu、Ni掺杂的镁铝水滑石结晶状况良好,呈现水滑石特有的7个衍射峰,未出现CuO、NiO的衍射峰。Cu、Ni的掺杂浓度越高,比表面积越小。SEM分析显示,类水滑石前驱体呈典型层状结构,经过焙烧后,层状结构消失,氧化物粒子发生团聚。随着Cu/Ni比增加,酮类产物收率呈逐渐增加趋势;在Cu/Ni比为1∶1时,醇类和烃类产物含量最多,而酚类和酯类含量最少。随着催化剂用量增加,酮类、醇类和烃类收率逐渐增加,特别是在用量20%时上升趋势尤为明显。反应温度高于甲醇的超临界温度时,酮类、醇类和烃类等含氧量相对较低的产物呈大幅度上升,而酯类和其他产物(主要包括醚类、酸类、呋喃类等)显著下降。【结论】CuO和NiO在复合氧化物中高度分散,掺杂的PMO具有更小的比表面积。甲醇的超临界温度是影响液化产物组成和分布的关键因素。随着竹材液化反应深入进行,不饱和官能团在甲醇裂解提供的原位供氢体系中发生加氢还原反应,生成含氧量相对较低的醇类、酮类和烃类产物。Ni的添加能够提高催化剂活性组分Cu的分散度,改善催化剂结构并提高其稳定性,从而提高催化剂对竹材液化的催化活性,同时Ni的加入和含量的增加可使混合氧化物的酸、碱性得到调变,改变PMO催化剂的催化活性,促进产物定向分布。【Objective】Here,we reported one-pot catalytic conversion of bamboo to liquid fuels,and investigated the effect of reaction factors on the liquefaction products of biomass catalyzed by Cu and Ni-doped porous metal oxides(PMO)in supercritical methanol,revealing the role of active components in liquefaction of bamboo.【Method】Cu-Ni-doped PMO catalysts were prepared through coprecipitation using hydrotalcite-like as precursors.The catalysts were characterized by XRD,BET and SEM.The liquefaction of bamboo was accomplished using a one-pot method in supercritical methanol,and the liquefied products were analyzed by GC-MS.Effects of Cu/Ni ratio,catalyst dosage,reaction temperature and time on the composition and distribution of bamboo liquefaction products were investigated by single factor analysis.【Result】XRD results suggested that the Cu and Ni doped Mg-Al hydrotalcite crystallized well,showing seven unique diffraction peaks of hydrotalcite and no diffraction peaks of CuO and NiO.The higher doping concentration of Cu and Ni,the smaller specific surface area of PMO.SEM analysis showed that the hydrotalcite-like precursor had a typical layered structure,while the layered structure disappeared and the oxide particles were agglomerated after calcination.The yield of ketones was increased gradually with the increase of Cu/Ni ratio.The yields of alcohols and hydrocarbons were the highest with a Cu/Ni ratio of 1∶1,while the phenols and esters were the least.The yields of ketones,alcohols and hydrocarbons were gradually increased along with the catalyst dosage increased.In particular,the rising trend was evident when 20%of catalysts were used.When the reaction temperature was higher than the supercritical temperature of methanol,the products with relatively low oxygen content,such as ketones,alcohols and hydrocarbons,showed a sharp rise.However,esters and other products(mainly including ethers,acids,furans,etc.)were decreased significantly.【Conclusion】CuO and NiO are highly dispersed in the complex oxides,and

关 键 词：液化 液体燃料 金属氧化物 超临界甲醇 加氢 

分 类 号：TK6[动力工程及工程热物理—生物能]