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Hyo Seon Kim Mi-Ra Park Sung-Koo Kim Gwi-Taek Jeong 《Korean Journal of Chemical Engineering》2018,35(6):1290-1296
As a potential renewable aquatic resource, chitosan is the second most abundant biopolymer. Methanesulfonic acid is a catalyst that is strongly acidic and biodegradable. We used chitosan and methanesulfonic acid to produce platform chemicals via an acid-catalyzed hydrothermal reaction. In the methanesulfonic acid-catalyzed hydrothermal conversion of chitosan, an optimal levulinic acid yield of 28.21±1.20% was achieved under the following conditions: 2% chitosan and 0.2 M methanesulfonic acid at 200 °C for 30 min. These results indicated that a combination of chitosan and methanesulfonic acid would be suitable for platform chemical production. 相似文献
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Whittaker JW 《Chemical reviews》2003,103(6):2347-2363
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采用柠檬酸络合法,通过调整CeO2含量(x=5%、10%、20%、30%)(以Al2O3的质量计,下同)制备出一系列xCeO2-Al2O3复合氧化物,以此为载体用沉积-沉淀法制备了Pd负载量(以Al2O3的质量计,下同)为5%的5%Pd/xCeO2-Al2O3催化剂.采用XRD、N2吸附-脱附、TEM、XPS对催化剂的物化性质进行了表征,探讨了催化剂对生物质基乙酰丙酸与腈类化合物"一锅法"还原胺化合成N-取代基-5-甲基-2-吡咯烷酮类化合物的催化性能.结果表明,在温和的反应条件下(90℃、1.5 MPa H2),催化剂5%Pd/10%CeO2-Al2O3上乙酰丙酸与苯甲腈反应5 h,N-苄基-5-甲基-2-吡咯烷酮收率高达87.5%.在该催化剂上,乙酰丙酸(酯)与其他多种腈类化合物反应同样获得了较高的吡咯烷酮类化合物收率(76.3%~87.4%).催化剂5%Pd/10%CeO2-Al2O3循环4次后,活性无明显下降. 相似文献
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Zhong-Ming Wang Jin-Suk Lee Ji-Yeon Park Chuang-Zhi Wu Zhen-Hong Yuan 《Korean Journal of Chemical Engineering》2008,25(4):670-674
As a kind of waste collected from restaurants, trap grease is a chemically challenging feedstock for biodiesel production
for its high free fatty acid (FFA) content. A central composite design was used to evaluate the effect of methanol quantity,
acid concentration and reaction time on the synthesis of biodiesel from the trap grease with 50% free fatty acid, while the
reaction temperature was selected at 95 °C. Using response surface methodology, a quadratic polynomial equation was obtained
for ester content by multiple regression analysis. Verification experiments confirmed the validity of the predicted model.
To achieve the highest ester content of crude biodiesel (89.67%), the critical values of the three variables were 35.00 (methanol-to-oil
molar ratio), 11.27 wt% (catalyst concentration based on trap grease) and 4.59 h (reaction time). The crude biodiesel could
be purified by a second distillation to meet the requirement of biodiesel specification of Korea. 相似文献
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农产品副产物生产乙酰丙酸 总被引:1,自引:0,他引:1
徐兆瑜 《精细化工原料及中间体》2006,(5):35-38
乙酰丙酸是一种可望作为制备多种化工产品的新型平台化合物和医药中间体,它可利用丰富的再生资源废弃物或副产物如:玉米芯、造纸废纤维、糠醛渣、木糖楂等来制备。目前制备方法有糠醇(醛)催化水解和生物质水解法,乙酰丙酸用途广泛,是重要的化工原料,市场前景看好。 相似文献
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Soares Dias Ana Paula Gomes Fonseca Frederico Catarino Mnica Gomes Joo 《Catalysis Letters》2022,152(2):513-522
Catalysis Letters - Current industrial methods of biodiesel production lead to an excess of crude glycerin which requires costly purification before commercialization. Production of oxygenated fuel... 相似文献
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硫酸催化葡萄糖制备乙酰丙酸的过程强化 总被引:1,自引:0,他引:1
采用高温下稀硫酸催化葡萄糖的方法制备乙酰丙酸。考察了反应温度、硫酸浓度和搅拌转速对葡萄糖转化率和乙酰丙酸收率的影响,并优化确定了最优反应条件。进一步,分析了最优反应条件下不同葡萄糖初始浓度对乙酰丙酸收率的影响。为了提高高浓度葡萄糖底物反应时乙酰丙酸的收率,采用两种不同的补料方法进行实验:分3次,依次加入7%、6%与5%的葡萄糖;每次均添加3%的葡萄糖,共6次。结果表明:①提高硫酸浓度、反应温度和搅拌速度有利于加快葡萄糖转化和乙酰丙酸生成;②高浓度葡萄糖底物不利于乙酰丙酸的生成,且浓度越高,乙酰丙酸收率越低;③通过补料操作,可使乙酰丙酸收率由 44.3%提高至65.9%。 相似文献
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Hartmut Widdecke 《Polymer International》1984,16(4):188-192
The present state of polymer-supported acid catalysis is considered. Models describing the catalytic action of gel-like and macroporous resin catalysts are presented. By chemical modification of poly (styrene-co-divinylbenzene) matrices, e.g. different ways of sulphonation, nitration, chlorination, fluorination and sulphoalkylation, the activity/selectivity and thermal stability of sulphonic acid resin catalysts can be improved. The synthesis of polymer-supported Lewis acids is described. By comparison to AlCl3 higher catalytic activities are obtained with the use of AlBr3. 相似文献
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以加拿大一枝黄花为原材料,提取α-纤维素,并制备乙酰丙酸。在符合生物炼制观念的基础上,考察温度、时间、酸浓度、固液比对乙酰丙酸的产率和还原糖残留量的影响。采用气相色谱法进行产率的分析。结果表明,压力为2.0 MPa时,在最佳温度230℃,时间45 min,硫酸浓度为6%,固液比1∶20的条件下,乙酰丙酸的产率为27.62%。反应结束之后,还原糖基本完全转化,残留量为1.02%。 相似文献
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An-Jie Zhang Ai-Min Zhu Jun Guo Yong Xu Chuan Shi 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2010,156(3):601-606
The topics on conversion and utilization of methane and carbon dioxide are important issues in tackling the global warming effect from the two greenhouse gases. In the present study, pure plasma and plasma catalytic activation of methane and carbon dioxide were investigated for syngas production. For pure plasma process, the effects of discharge power, CH4/CO2 ratios in the feed, total flow rate, as well as the concentration of the balanced gas of Ar were studied. Ar in the feed has great effects on the conversion and the stability of the reaction. At 120 °C and atmospheric pressure, the conversion of CH4 increased from 39% to 56% and that of CO2 increased from 23% to 30% when the Ar content in the feed increased from 0% to 50%, whereas Ar showed little effect on the H2/CO ratios in the products. Moreover, the conversions of CH4 and CO2 remained unchanged within the testing hours in the presence of 50% of Ar, which was contrastive with those obtained without Ar in the feed. When Cu–Ni/Al2O3 catalyst was filled in the discharge gap at 450 °C, the synergism between the catalyst and dielectric-barrier discharge (DBD) plasma was achieved. Conversions of CH4 for plasma alone, plasma-catalysis and catalysis alone were 13%, 69% and 10%, respectively. Selectivities to CO and H2 under the plasma-catalytic process were, respectively, 76% and 57%. 相似文献
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制备了一系列Brønsted-Lewis双酸性离子液体催化剂,并将其应用于纤维素制备乙酰丙酸的实验中。考察催化剂种类、催化剂用量、反应温度、反应时间和催化剂重复使用次数对乙酰丙酸收率的影响,得到最佳工艺条件:[HO3S-(CH2)3-mim]Cl-FeCl3(FeCl3物质的量分数为0.60)用量0.62 mmol、纤维素用量0.50 g、反应温度180 ℃、反应时间10 h、去离子水用量为30 mL。在该反应条件下,乙酰丙酸收率为49.47%。通过甲基异丁基酮萃取可以分离出乙酰丙酸和催化剂。催化剂重复使用5次后,乙酰丙酸收率仍大于44%。采用SEM、XRD和TG-DTG对固体残余物进行表征,结果发现,纤维素转化成乙酰丙酸的过程中伴随着腐殖质的生成。 相似文献
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Oligomerization of terminal and internal long-chain, linear olefins has been successfully demonstrated using large pore zeolites with high silica-to-alumina ratios as catalysts. Both reactant and product selectivities have been demonstrated using 12-membered ring zeolites for the oligomerization of C12–C18 olefins. The catalytic activity of these zeolites decreases in the order faujasite > mordenite > pentasil; the activity of the Y-zeolites depends primarily upon the silica-to-alumina molar ratio, but not on the total acidity. 1-tetradecene oligomerization, followed by oligomer hydrogenation, yields synthetic lubricant base stocks with excellent physical characteristics. 相似文献
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制备了一系列金属离子修饰的磷钨酸盐(MXH3-2XPW12O40,M=Zn,Cu,Cs,Ag)催化剂,并将磷钨酸银盐(Ag3PW12O40)用于水解葡萄糖制备乙酰丙酸的实验中。采用FTIR、XRD、SEM和EPMA等技术对磷钨酸盐性能进行了表征,并分析了磷钨酸银盐催化剂在反应前后结构和表面元素相对含量的变化。考察了反应温度、反应时间、催化剂用量和葡萄糖浓度等对乙酰丙酸得率的影响。结果表明:合成的磷钨酸盐具有磷钨酸的Keggin结构,并且Ag3PW12O40催化剂在多次使用后Keggin结构没有被破坏。在催化合成反应中,在反应温度200℃、反应时间2 h、Ag3PW12O40催化剂用量0.7 g和葡萄糖浓度40 g·L-1的条件下,乙酰丙酸的最大得率可达到81.61%,催化剂可重复利用。 相似文献