Bagasse was liquefied in supercritical water at 375-400 ℃,in the presence of Na_2CO_3,K_2CO_3,or NaOH as catalyst.The effects of liquid ratio,time,temperature and catalyst on the liquefaction were investigated.The minimum residue yield of 10 % was achieved at 20 min when liquefaction was conducted at 380 ℃ with liquid-solid ratio 18 : 1 and Na_2C0_3 (or NaOH) dosage 1 %.The residue was below 7 % under similar condition when the dosage of K_2CO_3 was 3 %.Liquid products of the reaction comprised of cyclic ketone and various phenolic compounds containing methyl and hydroxyl groups.Gaseous products formed during liquefaction,which were C_1-C_4 hydrocarbons,CO,CO_2 and H_2,varied with temperature.Solid residues were composed of char and residual lignin,according to FT-IR and SEM analysis.%以Na_2 CO_3、K_2 CO_3、NaOH为催化剂,在375 ~ 400℃的超临界水中进行蔗渣的液化反应.考察了液固比、反应时间、反应温度和催化剂对蔗渣液化的影响.在380℃、液固比18∶ 1(质量比)、反应时间20min条件下,NaOH或Na_2 CO_3催化剂用量为1%时, 液化残渣率降到10%以下,而在同样条件下,K_2 CO_3催化剂用量为3%时,液化反应的残渣率降到7%以下.对液化产物进行了表征.GC - MS分析表明,液体产物的主要组成是含环状结构的酮和一些含甲基、羟甲基等官能团的苯酚类化合物,气体产物主要为C_1～C_4烷烃和CO、CO_2、H_2等无机气体,且其组成因液化温度而变化.液化残渣经过FT - IR分析和扫描电镜分析,发现其主要由焦炭以及尚未完全分解的木质素组成.
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