Integrated process for hydrogenation and catalytic cracking of hydrocarbon oil (China Petroleum And Chemical)

CATEGORY: HYDROGENATION
Integrated process for hydrogenation and catalytic cracking of hydrocarbon oil (China Petroleum And Chemical)

Type	Patent
Inventor	Yongcan Gao
Inventor	Chaogang Xie
URL	Free Full Text Source:  http://www.google.com/patents/US9309467
Assignee	China Petroleum And Chemical Corp.,
Patent Number	US9309467 B2
Issue Date	Apr 12, 2016
Abstract	Disclosed is a combination process for improved hydrotreating and catalytic cracking of hydrocarbon oils, including: contacting residual oil, catalytic cracking cycle oil, and optional distillate oil with a hydrotreating catalyst under hydrotreating conditions in the presence of hydrogen followed by separation of the reaction products to obtain gas, hydrogenated naphtha, hydrogenated diesel oil, and hydrogenated tail oil; contacting the hydrogenated tail oil and optional normal catalytic cracking feedstock oil with a cracking catalyst under catalytic cracking conditions followed by separation of the reaction products to obtain dry gas, hydrogenated naphtha, liquefied petroleum gas, catalytic cracked gasoline, catalytic cracked diesel oil, and catalytic cracking cycle oil; wherein the hydrogenated tail oil and/or normal catalytic cracking feedstock oil are separated into at least two fractions, the light and the heavy fractions or normal catalytic cracking heavy feedstock oil and normal catalytic cracking light feedstock oil, prior to contacting the hydrogenated tail oil and/or normal catalytic cracking feedstock oil with the cracking catalyst. The process according to the present invention is especially suitable for conversion of hydrocarbon oils to produce more products of gasoline or diesel oil.

A Hydrogenation Catalyst, Its Method of Preparation and Use (ExxonMobil)

CATEGORY: HYDROGENATION
A Hydrogenation Catalyst, Its Method of Preparation and Use (ExxonMobil)
United States Patent Application 20160193592
Bai; Chuansheng ;   et al.   July 7, 2016
Applicant: Exxonmobil Chemical Patents Inc
Abstract
A method of preparing a hydrogenation catalyst, for example, a phthalate hydrogenation catalyst, comprising contacting a silica support having a median pore size of at least about 10 nm with a silylating agent to form an at least partially coated silica support, calcining said coated silica support to form a treated silica support, and depositing a noble metal, preferably ruthenium, on the treated silica support, and optionally contacting the treated silica support with an optional chelating agent to form the hydrogenation catalyst; a hydrogenation catalyst prepared by that method; and a method of hydrogenating unsaturated hydrocarbons, such as phthalates, in which an unsaturated hydrocarbon is contacted with hydrogen gas in the presence of the hydrogenation catalyst of the invention.
FIELD OF THE INVENTION
[0002] The present invention relates to hydrogenation catalysts, in particular to methods for the preparation of noble metal catalysts, such as ruthenium (Ru) catalysts, for use in the hydrogenation of phthalates.
BACKGROUND
[0003] Plasticizers are incorporated into resins to increase their flexibility, workability, and dispensability. Phthalates, especially, the high molecular weight phthalates (HMWP), are used as plasticizers in PVC. Alternatives to phthalates are desirable due to environmental, legislative and regulatory concerns. In particular, the uses of phthalates as plasticizers are under severe pressure. Hydrogenation of phthalates produces 1,2-cyclohexyl dicarboxylates, hereinafter also referred to as cyclohexanoates, which can be also used as plasticizers.
[0004] Previous research showed that catalysts consisting of Ru supported on alumina (Al.sub.2O.sub.3) with low surface areas are active for the hydrogenation of phthalate to cyclohexanoates. U.S. Pat. No. 5,936,126 (BASF) discloses the hydrogenation of phthalates to cyclohexyl dicarboxylates using catalysts consisting of Ru supported on low surface area alumina at 80 to 120.degree. C. and under 10-20 MPa (100-200 atmospheres) pressure. US 2002/0019559 (BASF) discloses a catalyst for hydrogenation of phthalates comprising ruthenium deposited on an alumina support material that comprises macropores of greater than 50 nm in diameter.
[0005] It has also recently been discovered that materials consisting of Ru supported on a silica (SiO.sub.2) support with "remnant structure" produced by deposition of an organic ruthenium compound on a silica support to form an organic ruthenium complex on or in the support, followed by decomposition of the complex, have much higher activities and stabilities in the phthalate hydrogenation than reported Ru/Al.sub.2O.sub.3 catalysts. WO 2004/046076, WO 2004/045767 and WO 2004/046078 (ExxonMobil) disclose catalysts of Ru on silica supports prepared with the remnant structures. US 2012/0296111 (BASF) discloses an eggshell catalyst for hydrogenating carbocyclic aromatic compounds, such as phthalates, comprising a noble metal, such as ruthenium, deposited on a silica support material in which at least 90% of the pores present have a pore diameter of 6 to 12 nm. The catalysts may be prepared by depositing ruthenium acetate on the silica support and then reducing.
[0006] Large pore extruded silica is a commercial catalyst support. US 2010/0133148 (ExxonMobil) discloses a hydrodesulfurization catalyst comprising cobalt and molybdenum salts impregnated on large pore silica supports. The catalyst is prepared by impregnating the silica support with a solution containing the metal ions, an organic additive, which is an alcohol or aminoalcohol, an organic acid and an inorganic acid. US 2012/0184430 (Samsung) discloses the synthesis of a metal oxide support material, such as mesoporous silica, that has surface hydroxyl groups, including hydroxyl groups within its pores, and the preparation of a carbon dioxide reforming catalyst comprising a metal deposited onto that support material. However, the use of large pore silica as an effective support for ruthenium in a phthalate hydrogenation catalyst has not previously been achieved.
[0007] It has also been found that large pore silica support can facilitate the mass transfer of large molecules of phthalate during catalytic reactions, which can be beneficial to the catalyst activity for phthalate hydrogenation to cyclohexanoates. However, in order to have large pores and high crush strength, the silica support is steam-treated at high temperature. During the high temperature steam-treatments, improved extrudate crush strength and large porosity are accompanied by decreases in hydroxyl group concentration and surface area of the steamed silica support. As a consequence, known strong and large pore silica supports usually have low surface areas and low concentration of hydroxyl groups due to high temperature steaming. Si--OH hydroxyl groups are required for complexion to noble metals, such as ruthenium. Therefore, commercially available large pore silica are not particularly suitable for use as ruthenium supports for phthalate hydrogenation catalysts.
[0008] There remains a need for metal oxide-supported noble metal catalysts which are highly active in phthalate hydrogenation. In particular, there remains a need for a metal oxide support that can both facilitate the mass transfer of large molecules of phthalate during catalytic reactions and which has a high concentration of hydroxyl (Si--OH) groups for complexion to noble metals, such as ruthenium.
SUMMARY OF THE INVENTION
[0009] In a first aspect, the invention provides a method for the synthesis of a silica-supported noble metal catalyst, in particular a silica-supported ruthenium catalyst, in which a noble metal, preferably ruthenium, and optionally a chelating agent, is deposited onto a silica support that has been treated to add a fresh layer of silica onto the surface of the silica support material. Advantageously, the treatment of the silica support increases the concentration of hydroxyl (Si--OH) groups on the surface. In one embodiment, the invention provides a method for the preparation of a silica-supported noble metal (e.g., ruthenium) hydrogenation catalyst comprising the steps of: (a) contacting a silica support with a silylating agent to coat at least a part of the silica support to produce a coated silica support; (b) calcining the coated silica support obtained in step (a) to produce a treated silica support; and (c) depositing a noble metal (e.g., ruthenium) on the treated silica support obtained in step (b), such as by contacting the treated silica support obtained in step (b) with a solution comprising said noble metal (e.g., ruthenium) and an optional chelating agent, for instance triethanolamine (TEA), to produce a noble metal-containing silica support. The noble metal-containing silica support obtained in step (c) may be used as such as hydrogenation catalyst or it may be subjected to further processing steps before being used as a catalyst. The silica support used in step (a) is preferably a large pore silica support, for example, produced by steam-treating. The silica may, for example, have a median pore size of at least 10 nm, especially at least 20 nm.
[0010] Additionally or alternatively, the silica support may have a high crush strength, for example, a crush strength of at least 800 g/mm, in particular at least 1000 g/mm. The method may further comprise the step of steam-treating a silica to produce the silica support used in step (a). The silylating agent is preferably a polysiloxane. In a preferred embodiment, the coated silica support of step (a) comprises at least a partial coating of a silylating agent on a large pore silica support. The method of the present invention optionally further comprises drying the coated silica support prepared in step (a), prior to calcining in step (b). The method of the first aspect of the invention optionally further comprises the step of drying and/or (d) calcining the noble metal-containing silica support obtained in step (c). The method optionally further comprises the step (e) of activating the catalyst for instance by contacting the noble metal-containing silica support obtained in step (c) or (d) with hydrogen gas to form an activated catalyst.
[0011] In a second aspect, the invention provides a silica-supported noble metal catalyst comprising a noble metal, preferably ruthenium, dispersed on a large pore silica support coated with a fresh silica layer. In particular, the invention provides a silica-supported noble metal hydrogenation catalyst comprising a noble metal, preferably ruthenium, dispersed on a silica support, wherein the median pore size of the catalyst is at least about 10 nm, especially at least 20 nm. Advantageously, the catalyst of the second aspect of the present invention has a hydrogen to noble metal chemisorption ratio of at least about 0.50, especially at least 0.60.
[0012] Advantageously, the catalyst of the second aspect of the invention has a crush strength of at least 800 g/mm, in particular at least 1000 g/mm. The silica-supported noble metal, preferably ruthenium, catalyst of the second aspect of the invention may, for example, be prepared by the method of the first aspect of the invention. The hydrogenation catalysts of the invention are suitable for the catalysis of hydrogenation processes, for example, processes in which unsaturated hydrocarbons, such as aromatic compounds, are hydrogenated using hydrogen gas, especially for use in phthalate hydrogenation processes.
[0013] In a third aspect, the invention provides a method of hydrogenating phthalates comprising the step of contacting a phthalate with a catalyst of the second aspect of the invention or a catalyst obtainable or obtained by the method of the first aspect of the invention, for example, in the presence of hydrogen gas.
[0014] In a fourth aspect, the invention provides a method of increasing the concentration of hydroxyl (Si--OH) groups on the surface of a silica catalyst support material, for example, a large pore silica support, such as a silica support having a median pore size of at least 10 nm, especially at least 20 nm, comprising the step of treating the silica support with a silylating agent. For example, the invention provides a method of increasing, for example, repopulating, the hydroxyl group concentration of a silica support following steam treatment, the method comprising the step of treating the silica support by contacting with a silylating agent and then calcining.
[0015] In a fifth aspect, the invention provides a silica support having a median pore size of at least 10 nm, especially at least 15 nm, and a hydroxyl group concentration sufficient to provide a catalyst having hydrogen to noble metal chemisorption ratio of at least 0.5, especially at least 0.6, following deposition of the noble metal on the catalyst surface. Advantageously, the large pore silica support of the fifth aspect of the invention or prepared by the fourth aspect of the invention has a crush strength of at least 800 g/mm, for example, at least 1000 g/mm. The silica support of the fifth aspect of the invention may, for example, be prepared by increasing the hydroxyl (Si--OH) group concentration of a large pore silica support, such as a commercially available large pore silica support, or a silica support which has been steam-treated, in accordance with the method of the fourth aspect of the invention.
[0016] It has been found that treating silica supports with a silylating agent to form a silica coating or silica layer at the surface of the silica support improves the dispersion of noble metals, for instance ruthenium, onto the silica support. Without wishing to be bound by any theory, it is believed that treating a silica support that has been modified by high temperature steaming with a silylating agent, repopulates the hydroxyl groups on silica surface increasing the concentration of hydroxyl groups for noble metal anchoring and restores the surface areas which were lost during the high temperature steaming. It has also been found that following coating of the silica supports with fresh layers of active silica, the properties of high crush strength and large porosity of a steam-treated silica support are preserved. Hydrogen chemisorption experiments have demonstrated that noble metal dispersion on a large pore silica support suitable for phthalate hydrogenation is greatly improved with treated silica supports of the invention. To form silica-supported noble metal hydrogenation catalysts of the invention, the noble metal is preferably dispersed on a treated silica support with a chelation aid. Suitable chelation aids include amino alcohols, such as triethanolamine (TEA). For instance, TEA and Ru ions form complexes of Ru-TEA, which are anchored to the silica surface via the interactions with hydroxyl groups of a silica support. The hydroxyl groups of the silica support are the anchoring points for noble metal dispersion.
Free Full Text Source:  http://appft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=OR&d=PG01&s1=exxonmobil.AS.&s2=exxonmobil.AANM.&OS=AN/exxonmobil+OR+AANM/exxonmobil&RS=AN/exxonmobil+OR+AANM/exxonmobil

Fluorescence-marked mesoporous silica core–shell nanocatalyst for asymmetric transfer hydrogenation

CATEGORY: CATALYSIS: HYDROGENATION
Fluorescence-marked mesoporous silica core–shell nanocatalyst for asymmetric transfer hydrogenation

Type	Journal Article
Author	Juzeng An
Author	Junwei Zhao
URL	http://www.sciencedirect.com/science/article/pii/S0925400515305268
Volume	224
Pages	333-337
Publication	Sensors and Actuators B: Chemical
Date	March 1, 2016
Abstract	Researchers fabricated fluorescence-marked core–shell structured nanocatalyst using the co-condensation method. The catalyst displayed good catalytic efficiency for asymmetric transfer hydrogenation of aromatic ketones and could be recovered and reused several times. The strong fluorescent emission easily tracks the recovery process of the nanocatalyst.