A skeletal isomerization process for isomerizing olefins is described. The process includes the steps of feeding an olefin-containing feed to a reactor at a space velocity of 1-100 hr.sup.−1 for a first period of time at a first temperature, followed by discontinuing, or stopping, the olefin-containing feed for a second period of time while maintaining the reactor at a second temperature, before resuming the flow of the olefin-containing feed for a third period of time. The methods of this disclosure increase the yield of the skeletal isomers product while reducing the production of C5+ heavy olefins. Additionally, the methods of this disclosure can be applied to feeds containing iso-olefins (for the production of linear olefins) or linear olefins (for the production of iso-olefins).

A skeletal isomerization process for isomerizing olefins is described. The process includes the steps of feeding an olefin-containing feed to a reactor at a space velocity of 1-100 hr.sup.−1 for a first period of time at a first temperature, followed by discontinuing, or stopping, the olefin-containing feed for a second period of time while maintaining the reactor at a second temperature, before resuming the flow of the olefin-containing feed for a third period of time. The methods of this disclosure increase the yield of the skeletal isomers product while reducing the production of C5+ heavy olefins. Additionally, the methods of this disclosure can be applied to feeds containing iso-olefins (for the production of linear olefins) or linear olefins (for the production of iso-olefins).

A skeletal isomerization process for isomerizing olefins is described. The process includes the steps of feeding an olefin-containing feed to a reactor at a space velocity of 1-100 hr.sup.−1 for a first period of time at a first temperature, followed by discontinuing, or stopping, the olefin-containing feed for a second period of time while maintaining the reactor at a second temperature, before resuming the flow of the olefin-containing feed for a third period of time. The methods of this disclosure increase the yield of the skeletal isomers product while reducing the production of C5+ heavy olefins. Additionally, the methods of this disclosure can be applied to feeds containing iso-olefins (for the production of linear olefins) or linear olefins (for the production of iso-olefins).

A skeletal isomerization process for isomerizing olefins is described. The process includes the steps of feeding an olefin-containing feed to a reactor at a space velocity of 1-100 hr.sup.−1 for a first period of time at a first temperature, followed by discontinuing, or stopping, the olefin-containing feed for a second period of time while maintaining the reactor at a second temperature, before resuming the flow of the olefin-containing feed for a third period of time. The methods of this disclosure increase the yield of the skeletal isomers product while reducing the production of C5+ heavy olefins. Additionally, the methods of this disclosure can be applied to feeds containing iso-olefins (for the production of linear olefins) or linear olefins (for the production of iso-olefins).

Disclosed are heterostructured silica catalysts (modified Haider heterostructured silica) and methods of their use and preparation. The heterostructured silica catalysts include a transition metal, an alkaline earth metal oxide, and silica, wherein the transition metal, the alkaline earth metal from the metal oxide thereof, and silicon (Si) from silica are each present in the crystal lattice structure of the catalyst. The catalyst can have application in, e.g., the hydrogenation of carbon monoxide.

The present disclosure discloses a method for preparing caprolactam including: (1) contacting cyclohexanone oxime with a catalyst to carry out reaction in the presence of ethanol and under the condition of gas phase Beckmann rearrangement reaction of cyclohexanone oxime; (2) separating the reaction product obtained in step (1) to produce an ethanol solution of crude caprolactam, and then separating the ethanol solution of crude caprolactam to obtain ethanol and crude caprolactam; (3) removing impurities with boiling points lower than that of caprolactam in the crude caprolactam to obtain a light component removal product; (4) mixing the light component removal product with a crystallization solvent to carry out crystallization and solid-liquid separation to obtain a crystalline crystal; (5) subjecting the crystalline crystal to a hydrogenation reaction; wherein the crystallization solvent contains 0.1-2 wt % of ethanol.

This invention belongs to the technical field of green preparation of environmentally friendly catalysts, and discloses a preparation method and application of mesoporous FeCu—ZSM-5 molecular sieve, in particular to a method for synthesizing mesoporous FeCu—ZSM-5 molecular sieve by one-pot method and the application in selective catalytic reduction (SCR) denitration reaction. This invention firstly proposes to combine the two calcinations after demolding and ion exchange into one, that is, the original powder is directly calcined to prepare a FeCu—ZSM-5 molecular sieve. The molecular sieve has several advantages such as window with wide temperature window, low cost, good hydrothermal stability and high SCR denitrification activity. Besides, the synthesis process does not use a (large) pore template, nor does it use a post-treatment method to construct the mesopores. Therefore, the method of the invention not only has the advantages of simple process, simple operation, but also good economic and environmental benefits.

The present disclosure provides a sound absorbing material. The sound absorbing material comprises MFI-structural-type zeolite. The MFI-structural-type zeolite comprises a framework, and the framework comprises SiO.sub.2 and AlO.sub.3, and the mass ratio of Si to Al in the framework is less than 200 and not less than 50. The present disclosure also provides a speaker box applying the sound absorbing material. The sound absorbing material provided by the present disclosure and the speaker box using the sound absorbing material can further improve the performance of the speaker box, reduce the failure of zeolite and improve the performance stability of the speaker box.

The present invention deals with a process for catalytic cracking of hydrocarbons comprising vacuum gas oil, hydrotreated vacuum gas oil, unconventional light crude oil, preferably unconventional light crude oil type shale/tight oil and its blends with conventional vacuum gas oil, in order to generate products of major commercial value in the field of fuels, getting improved gasoline and coke yield, as well as the procedure for the preparation of a catalyst with essential physical properties of density and particle size to uphold it in a fluidized bed under the operation conditions in the catalyst evaluation unit at micro level, wherein the catalyst particles achieve a catalytic performance similar to fluidized microspheres in a reactor, without appreciable generation of fine particles.

A method of cementing may include preparing a cement composition comprising water, a hydraulic cement, and an agglomerated zeolite catalyst; placing the cement composition in a wellbore.