A method of manufacture of high-solids hydroxide slurries from caustic calcined carbonate powder is described, whereby the properties of the slurry are its low resistance to shear thinning to facilitate transport, a high stability for transport and storage, ease of reconstitution after long periods of storage, and, as required, a high concentration of chemically reactive species at the particle surface. The method achieves these specifications by mixing caustic calcined carbonate or hydroxide powder with water in an insulated reactor vessel, and agitating the slurry sufficiently such that the hydration reaction causes the water to spontaneously boil, such that the remaining hydration proceeds spontaneously under the fixed conditions of boiling through the water loss. The mixing process is preferably carried out by a shear pump. A viscosity modifier, such as acetic acid, is used to thin the slurry to enable the mixing system to maintain uniform mixing. The reaction is terminated when the boiling has spontaneously ceased and the temperature has spontaneously dropped to a set point though the reactor heat losses, where the processing time is sufficiently long that the slurry meets the desired specifications.

A system and method for charging a chromium-based catalyst to a mix vessel; introducing a reducing agent through an entrance arrangement into the mix vessel, and agitating a mixture of the chromium-based catalyst, the reducing agent, and a solvent in the mix vessel to promote contact of the reducing agent with the chromium-based catalyst to give a reduced chromium-based catalyst.

A polyester with ultra-high flowability and good stability over time is provided. The polyester can be polybutylene terephthalate (PBT) or another aliphatic polyester, whose intrinsic viscosity (IV) is less than 0.6 dL/g and a carboxylic end group (CEG) content is 15 meq/kg or less, and characterized by having a melt volume rate (MVR) of greater than 400 cm.sup.3/10 min at 250° C. A resin composition of this polyester is provided, which can be meltblown into microfibers of a uniform diameter and a concentrated diameter distribution, forming a fabric with a uniform small pore size.

Disclosed is a reactor for solution polymerization process using a metallocene catalyst for preparing polyolefin. The reactor includes: a reaction vessel for mixing a hydrocarbon-based solvent and an olefin monomer to produce polyolefin; a feed inlet installed at a lower portion of the reaction vessel to feed a feed including an unreacted monomer, a solvent, and a catalyst into the reaction vessel; a guide pipe having a cylinder shape being open at respective ends, installed along a central axis of the reaction vessel, and dividing an internal space of the reaction vessel into an up-flow region where a reaction mixture flows upward and a down-flow region where the reaction mixture flows downward; a swirling flow-inducing blade attached to the exterior surface of the guide pipe, causing the reaction mixture in the reaction vessel to rise along the exterior surface of the guide pipe while forming a swirling flow.

The present disclosure provides device comprising a cylindrical reaction vessel having one or more permeable cylindrical membranes disposed therein separating the cylindrical reaction vessel into at least a first portion and a second portion, wherein the one or more permeable cylindrical membranes are configured to permit first reactants from a first solution in the first portion or reactants from a second solution in the second portion to percolate or seep to a reaction zone proximate a surface of the one or more cylindrical membranes. A lifting device (mechanism) located above the first portion of the cylindrical reaction vessel configured to continuously draw a preform two-dimensional polymer tube formed by continuous reaction of the first and second reactants out from the reaction zone.

The present disclosure provides Lazarev reactor that sustains reaction of two dimensional polymerization on the interface of two immiscible solutions A and B carrying components of reaction to the interface where reaction takes place and produces film of two dimensional polymer layers that are pulled out of reactor and rolled up on roll after drying excess of solvent out.

A polyester with ultra-high flowability and good stability over time is provided. The polyester can be polybutylene terephthalate (PBT) or another aliphatic polyester, whose intrinsic viscosity (IV) is less than 0.6 dL/g and a carboxylic end group (CEG) content is 15 meq/kg or less, and characterized by having a melt volume rate (MVR) of greater than 400 cm.sup.3/10 min at 250° C. A resin composition of this polyester is provided, which can be meltblown into microfibers of a uniform diameter and a concentrated diameter distribution, forming a fabric with a uniform small pore size.

The present relates to the field of iron-doped TiO.sub.2 nanocrystals/photocatalysts and to a method of their production. The method comprising the steps: a) dissolving a compound comprising Fe (III); b) mixing an alcohol to the ferric solution to obtain a mixture; c) adjusting the pH of the mixture by adding a suitable acid to the mixture to obtain an acidic composition; d) producing a gelation reaction by mixing a titanium (IV) complex to the acidic composition, to obtain a dispersion comprising Fe-doped TiO.sub.2, e) drying the dispersion, to obtain a dried product substantially free of iron oxide contamination; f) grinding the dried product, to obtain a powder; g) washing the powder with an aqueous liquid, to obtain a washed powder comprising a Fe-doped TiO.sub.2 photocatalyst precursor; and h) drying the washed powder, to obtain the Fe-doped TiO.sub.2 photocatalyst precursor. The method further comprising calcining and grinding steps.

Disclosure relates to modified sulfur, preparation method thereof, preparation equipment thereof. The modified sulfur has spinnability or includes micro-structures such as fiber-, film- and network-like structure. The modified sulfur can be prepared by inducing polymerization with ultrasonic or ageing. The modified sulfur has various excellent features such as anticorrosiveness, waterproofing, strength, and fast drying and can control the features depending on its viscosity or polymerization degree. In addition due to the above features, the modified sulfur can be applied to anticorrosive or waterproofing material and can prepare anticorrosive or waterproofing material which has good workability, hardening, salt spray resistance, and weldability exceeding a certain level, and specially improved adhesiveness. Furthermore, when applying the modified sulfur to asphalt composition, gelation and depression are reduced, properties such as bending strength and tensile strength are improved, and it is possible to obtain asphalt composition with good working stability at RT.

The present invention relates to a method for preparing ZSM-5 zeolite. The present invention can provide a method for preparing ZSM-5 zeolite comprising the steps of: preparing a first solution in a solution state by heating a mixture comprising a silica source, an alumina source, a neutralizing agent and a crystalline ZSM-5 nucleus; preparing a reaction mother liquid by mixing a second solution comprising salts into the first solution; and continuously crystallizing by continuously supplying the reaction mother liquid to a hydrothermal synthesis reactor, wherein formula [1] below is satisfied.

0.20≤W.sub.a/W.sub.b≤0.40  Formula [1]