Single Chromium Atoms Supported on Titanium Dioxide Nanoparticles for Synergic Catalytic Methane Conversion under Mild Conditions
作者:Qikai Shen、Changyan Cao、Runkun Huang、Lei Zhu、Xin Zhou、Qinghua Zhang、Lin Gu、Weiguo Song
DOI:10.1002/anie.201913309
日期:2020.1.13
of methane to value-added chemicals with high selectivity undermildconditions remains a great challenge in catalysis. Now, single chromium atoms supported on titanium dioxide nanoparticles are reported as an efficient heterogeneous catalyst for direct methane oxidation to C1 oxygenated products with H2 O2 as oxidant undermildconditions. The highest yield for C1 oxygenated products can be reached
The kinetics of complex formation between Ti(IV) and hydrogen peroxide
作者:Daniel W. O'Sullivan、Michael Tyree
DOI:10.1002/kin.20259
日期:2007.8
The kinetics of the formation of the titanium-peroxide [TiO2+2] complex from the reaction of Ti(IV)OSO4 with hydrogen peroxide and the hydrolysis of hydroxymethyl hydroperoxide (HMHP) were examined to determine whether Ti(IV)OSO4 could be used to distinguish between hydrogen peroxide and HMHP in mixed solutions. Stopped-flow analysis coupled to UV-vis spectroscopy was used to examine the reaction kinetics
Direct methane oxidation into value‐added organic oxygenates with high productivity under mild condition remains a great challenge. We show Fe‐O clusters on nodes of metal–organic frameworks (MOFs) with tunable electronic state for direct methane oxidation into C1 organic oxygenates at 50 °C. The Fe‐O clusters are grafted onto inorganic Zr6 nodes of UiO‐66, while the organic terephthalic acid (H2BDC)
在温和条件下以高生产率将甲烷直接氧化成增值有机含氧化合物仍然是一个巨大的挑战。我们显示了在可调节电子状态下,金属-有机骨架(MOF)上的Fe-O团簇可在50°C下将甲烷直接氧化成C1有机含氧化合物。Fe-O团簇接枝到UiO-66的无机Zr 6节点上,而UiO-66的有机对苯二甲酸(H 2 BDC)配体被乙酸(AA)或三氟乙酸(TFA)的单羧酸调节剂部分取代。实验和理论计算表明,TFA基团与Zr 6配位UiO-66的节点由于其吸电子能力而增强了相邻Fe-O团簇的氧化态,促进了甲烷的CH键的活化并增加了其选择性转化率,从而导致C1的C1含氧化合物的收率异常高4799μMOlg cat -1 h -1,选择性为97.9%,比AA调制的高约8倍。
Oligomerization Reaction of the Criegee Intermediate Leads to Secondary Organic Aerosol Formation in Ethylene Ozonolysis
作者:Yosuke Sakamoto、Satoshi Inomata、Jun Hirokawa
DOI:10.1021/jp408672m
日期:2013.12.5
Ethylene ozonolysis was investigated in laboratory experiments using a Teflon bag reactor. A negative ion chemical ionization mass spectrometer (NI-CIMS) using SO2Cl– and Cl– as reagent ions was used for product analysis. In addition to the expected gas-phase products, such as formic acid and hydroperoxymethyl formate, oligomeric hydroperoxides composed of the Criegee intermediate (CH2OO) as a chain
We carried out reactions of methyl-substituted cyclohexenes and α-pinene with ozone in air and elucidated the mechanisms of formation of the minor products (peroxides and formic acid). Peroxyacetic acid was formed only from the cyclohexenes with a methyl group on the double bond, whereas formic acid was produced in higher yields from the cyclohexenes without a methyl group on the double bond. These