化学研究
化學研究
화학연구
CHEMICAL RESEARCHES
2015年
5期
460-463
,共4页
钯纳米粒子%石墨烯%苯醌加氢%氢醌
鈀納米粒子%石墨烯%苯醌加氫%氫醌
파납미입자%석묵희%분곤가경%경곤
palladium nanoparticles%graphene%hydrogenation of benzoquinone%hydroquinone
采用微波辅助加热还原法合成了钯／石墨烯（Pd／G）、钯／活性炭（Pd／AC）、钯／石墨（Pd／Graphite）和钯／二氧化硅（Pd／SiO2），并使用透射电子显微镜观测了钯的形貌及在载体上的分散性。将负载型钯催化剂用于苯醌加氢反应，结果显示，Pd／G催化剂的活性最高，苯醌的转化率达到99％，氢醌的选择性为100％，并且循环7次后催化剂仍保持着较高的转化率和选择性。结构表征表明，石墨烯担载的钯纳米粒子的粒径约为5 nm ，无明显团聚。实验进一步考察了反应溶剂（甲醇、乙醇、丙酮、正丙醇、异丙醇、正丁醇）对 Pd／G催化苯醌加氢反应的影响，结果表明该反应对溶剂较为敏感，其中甲醇和丙酮较适宜作为反应溶剂。当以甲醇作为溶剂时，苯醌的转化率为98％，氢醌选择性为99％；以丙酮为溶剂时，苯醌转化率为98％，氢醌选择性为90％。研究工作表明，作为载体，石墨烯对钯催化剂的催化效果起着稳定和增强作用。
採用微波輔助加熱還原法閤成瞭鈀／石墨烯（Pd／G）、鈀／活性炭（Pd／AC）、鈀／石墨（Pd／Graphite）和鈀／二氧化硅（Pd／SiO2），併使用透射電子顯微鏡觀測瞭鈀的形貌及在載體上的分散性。將負載型鈀催化劑用于苯醌加氫反應，結果顯示，Pd／G催化劑的活性最高，苯醌的轉化率達到99％，氫醌的選擇性為100％，併且循環7次後催化劑仍保持著較高的轉化率和選擇性。結構錶徵錶明，石墨烯擔載的鈀納米粒子的粒徑約為5 nm ，無明顯糰聚。實驗進一步攷察瞭反應溶劑（甲醇、乙醇、丙酮、正丙醇、異丙醇、正丁醇）對 Pd／G催化苯醌加氫反應的影響，結果錶明該反應對溶劑較為敏感，其中甲醇和丙酮較適宜作為反應溶劑。噹以甲醇作為溶劑時，苯醌的轉化率為98％，氫醌選擇性為99％；以丙酮為溶劑時，苯醌轉化率為98％，氫醌選擇性為90％。研究工作錶明，作為載體，石墨烯對鈀催化劑的催化效果起著穩定和增彊作用。
채용미파보조가열환원법합성료파／석묵희（Pd／G）、파／활성탄（Pd／AC）、파／석묵（Pd／Graphite）화파／이양화규（Pd／SiO2），병사용투사전자현미경관측료파적형모급재재체상적분산성。장부재형파최화제용우분곤가경반응，결과현시，Pd／G최화제적활성최고，분곤적전화솔체도99％，경곤적선택성위100％，병차순배7차후최화제잉보지착교고적전화솔화선택성。결구표정표명，석묵희담재적파납미입자적립경약위5 nm ，무명현단취。실험진일보고찰료반응용제（갑순、을순、병동、정병순、이병순、정정순）대 Pd／G최화분곤가경반응적영향，결과표명해반응대용제교위민감，기중갑순화병동교괄의작위반응용제。당이갑순작위용제시，분곤적전화솔위98％，경곤선택성위99％；이병동위용제시，분곤전화솔위98％，경곤선택성위90％。연구공작표명，작위재체，석묵희대파최화제적최화효과기착은정화증강작용。
In the present study ,we exploited G as a support for palladium nanoparticles by mi‐crowave assisted reduction of palladium acetate with graphene under hydrogen atmosphere .In the same method ,we also employed graphite ,active carbon and silica as carrier for synthesis palladium graphite (Pd/Graphite) ,palladium active carbon (Pd/AC) and palladium silica (Pd/SiO2 ) .The hydrogenation of benzoquinone reaction has been selected as model reaction for e‐valuating G -based palladium catalysts (Pd/G) ,and the morphology and dispersion of palla‐dium on the carrier were observed by TEM .We utilized the supported palladium catalysts for benzoquinone hydrogenation reaction .The results imply that the Pd/G catalyst shows the high‐est activity .T he conversion of benzoquinone reached 99% and the selectivity to hydroquinone was 100% .In addtion ,the catalytic performance of Pd/G catalyst remained high even after seven reaction cycles .Structural characterization indicates palladium nanoparticles with an aver‐age size of 5 nm were uniformly distributed on the G support and they didn’t show obvious ag‐gregation .The study also found that the species of solvent(methanol ,ethanol ,acetone ,n‐pro‐panol ,isopropanol ,n‐butanol) had a great influence on catalytic hydrogenation of benzoqui‐none using Pd/G as catalysts .Methanol and acetone was suitable solvent for this reaction . When using methanol as solvent ,the conversion and selectivity were 98% and 99% ,respec‐tively ;for acetone ,the data were 98% and 90% .Research shows that G is an ideal carrier for palladium nanoparticles in hydrogenation reaction .
