工业催化
工業催化
공업최화
INDUSTRIAL CATALYSIS
2015年
8期
609-613
,共5页
王跃华%李婷婷%任开路%葛裕华
王躍華%李婷婷%任開路%葛裕華
왕약화%리정정%임개로%갈유화
催化化学%高分子%螯合反应%负载催化剂%选择性氯化%回收利用
催化化學%高分子%螯閤反應%負載催化劑%選擇性氯化%迴收利用
최화화학%고분자%오합반응%부재최화제%선택성록화%회수이용
catalytic chemistry%polymer%chelation%sUpported catalyst%selective chlorination%recycling
通过金属铁离子与高分子载体进行螯合反应，制备高分子负载铁催化剂，用原子吸收光谱法测定催化剂中 Fe3﹢含量，并利用傅里叶变换红外光谱仪、扫描电子显微镜、热重分析对制备的催化剂分子结构、微球形貌和热稳定性进行表征，并研究有机硫助催化剂的添加对高分子负载铁催化剂催化甲苯选择性氯化性能的影响。结果表明，铁离子与乙酰丙酮基的两个氧原子形成了六元螯合环的强相互作用，使 Cl2分子更易极化，提高了催化反应速率；有机硫助催化剂不仅改变 Cl—Cl键的强度，而且增大了亲电试剂的空间位阻，从而显著提高对位选择性和稳定性。1%（占甲苯的质量分数）高分子负载铁催化剂/0.05%（占甲苯的质量分数）有机硫助催化剂催化甲苯选择性氯化反应表现出最佳的催化性能，氯化反应2 h，甲苯转化率超过90%，对氯甲苯选择性55.74%，多氯甲苯质量分数低于1%。催化剂可重复使用。
通過金屬鐵離子與高分子載體進行螯閤反應，製備高分子負載鐵催化劑，用原子吸收光譜法測定催化劑中 Fe3﹢含量，併利用傅裏葉變換紅外光譜儀、掃描電子顯微鏡、熱重分析對製備的催化劑分子結構、微毬形貌和熱穩定性進行錶徵，併研究有機硫助催化劑的添加對高分子負載鐵催化劑催化甲苯選擇性氯化性能的影響。結果錶明，鐵離子與乙酰丙酮基的兩箇氧原子形成瞭六元螯閤環的彊相互作用，使 Cl2分子更易極化，提高瞭催化反應速率；有機硫助催化劑不僅改變 Cl—Cl鍵的彊度，而且增大瞭親電試劑的空間位阻，從而顯著提高對位選擇性和穩定性。1%（佔甲苯的質量分數）高分子負載鐵催化劑/0.05%（佔甲苯的質量分數）有機硫助催化劑催化甲苯選擇性氯化反應錶現齣最佳的催化性能，氯化反應2 h，甲苯轉化率超過90%，對氯甲苯選擇性55.74%，多氯甲苯質量分數低于1%。催化劑可重複使用。
통과금속철리자여고분자재체진행오합반응，제비고분자부재철최화제，용원자흡수광보법측정최화제중 Fe3﹢함량，병이용부리협변환홍외광보의、소묘전자현미경、열중분석대제비적최화제분자결구、미구형모화열은정성진행표정，병연구유궤류조최화제적첨가대고분자부재철최화제최화갑분선택성록화성능적영향。결과표명，철리자여을선병동기적량개양원자형성료륙원오합배적강상호작용，사 Cl2분자경역겁화，제고료최화반응속솔；유궤류조최화제불부개변 Cl—Cl건적강도，이차증대료친전시제적공간위조，종이현저제고대위선택성화은정성。1%（점갑분적질량분수）고분자부재철최화제/0.05%（점갑분적질량분수）유궤류조최화제최화갑분선택성록화반응표현출최가적최화성능，록화반응2 h，갑분전화솔초과90%，대록갑분선택성55.74%，다록갑분질량분수저우1%。최화제가중복사용。
A polymer-sUpported iron catalyst(YCH2 CHAcAc-Fe3 ﹢ )was prepared by chelation reaction of Fe3 ﹢ and polymer sUpport. The molecUlar strUctUre,microsphere morphology and thermal stability of the as-prepared catalyst was characterized by foUrier transform infrared spectrometer,scanning electron micro-scope and thermogravimetric analysis,and its iron content was determined by atomic absorption spectrom-etry. The effects of sUlfUr-containing cocatalyst(OS)on the catalytic properties of polymer-sUpported iron catalyst( YCH2 CHAcAc-Fe3 ﹢ )for the selective chlorination of tolUene were investigated. The resUlts showed that iron ions formed a chelated six-member ring with two oxygen atoms of acetylacetone,and Cl2 molecUles were easier to be polarized dUe to the strong interaction between iron ions and oxygen atoms,so the chlorination rates was improved;sUlfUr-containing cocatalyst(OS)not only changed the bond strength of Cl—Cl,bUt also increased the steric hindrance of electrophilic reagent,which greatly improved the catalytic selectivity and stability. YCH2CHAcAc-Fe3 ﹢ catalyst(1% of tolUene mass)with sUlfUr-containing cocatalyst(0. 05% of tolUene mass)exhibited the best catalytic performance Under the condition of room temperatUre and chlorination reaction time 2 h and coUld be recycled. TolUene conversion and the selec-tivity to p-chlorotolUene reached over 90% and 55. 74% ,respectively,and the mass fraction of byprodUct mUlti-chlorotolUene was controlled less than 1% .
