CAJ | 학술논문

以尿素为沉淀剂制备了纳米Ca-Mg-Al水滑石,采用X射线衍射、傅里叶变换红外光谱和扫描电子显微镜对其进行了表征,以其煅烧后得到的纳米Ca-Mg-Al复合金属氧化物为固体碱催化剂,采用微水相超声波辐射协同固体碱催化小桐子油与甲醇进行酯交换反应制备了生物柴油,并研究了催化剂的失活原因.实验结果表明,纳米Ca-Mg-Al水滑石的柱撑阴离子为CO_3~(2-),晶粒大小均匀,呈良好的层状结构.在超声波功率210 W、占空比0.7、反应时间30 min、温度60 ℃、甲醇与小桐子油摩尔比4:1、催化剂用量1.5%(基于小桐子油的质量)的反应条件下,生物柴油收率达94.3%,精制后的生物柴油完全符合德国生物柴油标准DIN V 51606:1997.催化剂失活的主要原因是层状结构的塌陷和副产物甘油附着在催化剂表面,使用后的催化剂用乙醇洗去表面的甘油后,可连续使用12次.
이뇨소위침정제제비료납미Ca-Mg-Al수활석,채용X사선연사、부리협변환홍외광보화소묘전자현미경대기진행료표정,이기단소후득도적납미Ca-Mg-Al복합금속양화물위고체감최화제,채용미수상초성파복사협동고체감최화소동자유여갑순진행지교환반응제비료생물시유,병연구료최화제적실활원인.실험결과표명,납미Ca-Mg-Al수활석적주탱음리자위CO_3~(2-),정립대소균균,정량호적층상결구.재초성파공솔210 W、점공비0.7、반응시간30 min、온도60 ℃、갑순여소동자유마이비4:1、최화제용량1.5%(기우소동자유적질량)적반응조건하,생물시유수솔체94.3%,정제후적생물시유완전부합덕국생물시유표준DIN V 51606:1997.최화제실활적주요원인시층상결구적탑함화부산물감유부착재최화제표면,사용후적최화제용을순세거표면적감유후,가련속사용12차.
Nano Ca-Mg-Al hydrotalcite was prepared by coprecipitation using urea as precipitation agent, and characterized by means of XRD, FTIR and SEM. With the aid of ultrasonic radiation, biodiesel were prepared from Jatropha oil and methanol in microaqueous media with calcined nano Ca-Mg-Al hydrotalcite as solid base catalyst. The results showed that Ca-Mg-Al hydrotalcite existed in laminar structure, particle size distributed uniformly, and the interlayer pillared anion was carbonate. Under conditions:ultrasonic power 210 W, duty ratio 0.7, reaction time 30 min, temperature 60 ℃, mole ratio of methanol to Jatropha oil 4 : 1 and catalyst mass fraction of 1.5% (based on Jatropha oil), yield of biodiesel was 94.3 %. The specifications of biodiesel after purification completely met DIN V 51606:1997. The main causes of catalyst de-activation were surface absorption of by-product glycerol, aggregation of catalyst particles and partial collapse of laminar structure. After removing the glycerol from surface of catalyst by washing with ethanol, the catalyst could be reused for 12 times.