摘要:
The invention relates to a process that results in a fluoropolymer composition with improved chemical, thermal and color stabilities, and a reduced level of residual surfactants (both fluorosurfactants and non-fluorosurfactants. Such improvements, as indicated by total oxidizable carbon (TOC) and pellet yellowness index (YI), can be accomplished in a cost-effect manner through the use of a dewatering extruder. The dewatering extruder combines several typical unit operations into a single operation, producing solid fluoropolymer having a significantly reduced total oxidizable carbons, a lower yellowness index and minimal amounts of surfactants.
摘要:
In the process of removing heavy metals from aqueous solutions by precipitation of a salt thereof at increased pH, multiple stage precipitation by upward stepwise pH adjustment and solid separation at each stage is used to facilitate the manufacture of a product of high purity.
摘要:
A process for removing sulfur from an organic polysulfide by reaction with an aqueous stripping solution of at least one sulfide salt and/or hydrosulfide salt in a multi-stage, continuous, countercurrent flow, reaction system wherein the sulfur is stripped from the polysulfide into the aqueous stripping solution phase which is separated from the polysulfide organic phase.
摘要:
Waxy distillate feedstocks are dewaxed by passing the waxy feedstock over a catalyst bed containing a mixture of medium pore zeolite and large pore zeolites having a Constraint Index less than 2 and having hydroisomerization activity in the presence of a hydrogenation component.
摘要:
There is provided a catalyst comprising a zeolite component and a microcrystalline, microporous aluminum phosphate component. Examples of the zeolite component are ZSM-5 and zeolite Beta, and an example of an aluminum phosphate component is AlPO.sub.4 -5. The aluminum phosphate component provides increased catalyst activity and lifetime. Also provided for in this disclosure are a method for making the zeolite/aluminum phosphate composite and a process for using this composite in the preparation or conversion of hydrocarbons, e.g., in a dewaxing process.
摘要:
The present invention relates to a process for the removal of solvent from a polymer emulsion or suspension, by use of a decanter centrifuge (10). The decanter centrifuge (10) provides an efficient thickening method. The process is especially useful for emulsion or suspension polymer compositions having high levels of solvent (low polymer solids) that could benefit from a thickening or dewatering step prior to drying in a dryer (14).
摘要:
In the process of removing heavy metals from aqueous solutions (groundwater) by precipitation of a salt thereof, an oxidizing agent is optionally used to increase the valence of said metal, and a precipitation-enhancing agent is added to maximize particle size of the precipitate and to facilitate its separation from said solution.
摘要:
Hydrocarbon lubricating oil feedstocks are dewaxed by passing the waxy feedstock over a catalyst bed containing a mixture of medium pore zeolite and large pore zeolite catalysts havig a Constraint Index less than 2 and having hydroisomerization activity in the presence of a hydrogenation component.
摘要:
Sulfur-laden liquid organic phase dimethyl polysulfide (DMPS) is caused to rise from a sour gas well by reaction of the gaseous sulfur component within the well with a sulfur solvent, typically dimethyl disulfide (DMDS). The DMPS is contacted by an extraction or stripping liquid in a vertical column continuous multistage countercurrent flow extractor especially designed to promote high interfacial area contact between the liquids while flowing in opposing directions within the column.
摘要:
Hydrocarbon feedstocks are dewaxed in a dual catalyst cascade process by passing the waxy feedstock over a crystalline silicate zeolite catalyst having a Constraint Index between 2 and 12, and then over a different crystalline silicate zeolite catalyst having a Constraint Index no less than 2.