摘要:
Supported catalysts include a solid support such as silica that is functionalized to have inorganic acid functional groups attached thereto. Active catalyst particles are supported on the functionalized support material. The acid functionalized support material is made by reacting a solid support with an inorganic acid containing agent such as sulfuric acid or para-toluene sulfonic acid. An organic anchoring agent is used to form and anchor catalyst nanoparticles to the acid functionalized support material. The supported catalyst can be sized and shaped for use in any type of reactor, including a fixed bed or fluidized bed reactor. The methods of the present invention also include a process for the direct synthesis of hydrogen peroxide using the supported catalyst.
摘要:
A process is disclosed for the direct catalytic production of aqueous solutions of hydrogen peroxide from hydrogen and oxygen in the presence of a small amount of one or more water soluble organic additives (about 0.1-10% by weight). Suitable catalysts include nanometer-sized noble metal catalytic crystal particles. The catalyst particles preferably have a controlled surface coordination number of 2 to increase the selectivity of hydrogen peroxide production. The water soluble additive(s) increases catalytic activity causing significant increases in the apparent first order reaction rate constant for the direct production of aqueous hydrogen peroxide.
摘要:
Method for making a direct synthesis hydrogen peroxide catalyst includes (i) mixing together a solvent, a plurality of noble metal catalyst atoms, and a plurality of organic dispersing agent molecules, the organic dispersing agent molecules each including at least one functional group capable of bonding with the noble metal catalyst atoms; (ii) reacting the organic dispersing agent with the catalyst atoms to form complexed catalyst atoms and forming a plurality of catalytic nanoparticles from the complexed catalyst atoms; (iii) supporting the catalytic nanoparticles on a support material; and (iv) reducing the catalyst atoms at a temperature of at least 351° C. to yield a supported and activated direct synthesis hydrogen peroxide catalyst.
摘要:
Disclosed are nanoparticles formed from a plurality of two or more different components. The two or more components are dispersed using a dispersing agent such that the nanoparticles have a substantially uniform distribution of the two or more components. The dispersing agents can be poly functional small organic molecules, polymers, or oligomers, or salts of these. The molecules of the dispersing agent bind to the particle atoms to overcome like-component attractions, thereby allowing different and/or dissimilar components to form heterogeneous nanoparticles. In one embodiment, dissimilar components such as iron and platinum are complexed using the dispersing agent to form substantially uniform heterogeneous nanoparticles. Methods are also disclosed for making the multicomponent nanoparticles. The methods include forming suspensions of two or more components complexed with the dispersing agent molecules. The suspensions can also be deposited on a support material and/or anchored to the support.
摘要:
Metal-containing colloids are manufactured by reacting a plurality of metal ions and a plurality of organic agent molecules to form metal complexes in a mixture having a pH greater than about 4.25. The metal complexes are reduced for at least 0.5 hour to form stable colloidal nanoparticles. The extended reduction time improves the stability of the colloidal particles as compared to shorter reduction times. The stability of the colloidal particles allows for colloids with higher concentrations of metal to be formed. The concentration of metal in the colloid is preferably at least about 150 ppm by weight.
摘要:
A process is disclosed for the direct catalytic production of aqueous solutions of hydrogen peroxide from hydrogen and oxygen in the presence of a small amount of one or more water soluble organic additives (about 0.1–10% by weight). Suitable catalysts include nanometer-sized noble metal catalytic crystal particles. The catalyst particles preferably have a controlled surface coordination number of 2 to increase the selectivity of hydrogen peroxide production. The water soluble additive(s) increases catalytic activity causing significant increases in the apparent first order reaction rate constant for the direct production of aqueous hydrogen peroxide.
摘要:
Supported reactive catalysts having a controlled coordination structure and methods for their production are disclosed. The supported catalysts of the present invention are useful for the preparation of hydrogen peroxide with high selectivity in addition to other chemical conversion reactions. The supported catalyst comprises catalyst particles having top or outer layer of atoms in which at least a portion of the atoms exhibit a controlled coordination number of 2. The catalyst and methods may be used for the concurrent in situ and ex situ conversion of organic compounds. In addition, a process is provided for catalytically producing hydrogen peroxide from hydrogen and oxygen feeds by contacting them with the catalysts of the invention and a suitable organic liquid solvent having a Solvent Selection Parameter (SSP) between 0.14×10−4 and 5.0×10−4.
摘要:
Supported reactive catalysts having a controlled coordination structure and methods for their production are disclosed. The supported catalysts of the present invention are useful for the preparation of hydrogen peroxide with high selectivity in addition to other chemical conversion reactions. The supported catalyst comprises catalyst particles having top or outer layer of atoms in which at least a portion of the atoms exhibit a controlled coordination number of 2. The catalyst and methods may be used for the concurrent in situ and ex situ conversion of organic compounds. In addition, a process is provided for catalytically producing hydrogen peroxide from hydrogen and oxygen feeds by contacting them with the catalysts of the invention and a suitable organic liquid solvent having a Solvent Selection Parameter (SSP) between 0.14×10−4 and 5.0×10−4.