摘要:
The invention concerns a process for the removal of gaseous acidic contaminants, especially carbon dioxide and/or hydrogen sulphide, in two or more stages from a gaseous hydrocarbonaceous feedstream (1) comprising hydrocarbons and said acidic contaminants, using one or more membranes in each separation stages. The gaseous hydrocarbonaceous feedstream is especially a natural gas stream. The process is especially suitable for feedstreams comprising very high amounts of acidic contaminants, especially carbon dioxide, e.g. more than 25 vol. %, or even more than 45 vol. %. In a first stage (2) a pure or almost pure stream of acidic contaminants is separated from the feedstream, the acidic contaminants (4) stream suitably containing less than 5 vol % of hydrocarbons. The remaining stream (3) comprises the hydrocarbons and still a certain amount of gaseous acidic contaminants. In a second stage (5) a pure or almost pure stream of hydrocarbons (8) is separated from the remaining stream, where after the then remaining stream (6) is combined with the feed for the first stage (1), the hydrocarbon stream suitably containing less than 5 vol % of acidic contaminants.
摘要:
A method of absorbing gases into a liquid comprising providing a stream of at least one desirable gas and at least one undesirable gas, exposing the gas stream to a liquid, so that the liquid absorbs more of the desirable gas than the undesirable gas, and releasing the liquid and gas mixture into an underground formation.
摘要:
A method of making a supported gas separation molecular sieve membrane. In this method a porous support, which is preferably pretreated, is contacted with a molecular sieve synthesis mixture under hydrothermal synthesis conditions. The contacting step is conducted for a shortened crystallization time period. The resulting coated porous support is calcined to yield the supported gas separation molecular sieve membrane having particularly good gas separation characteristics.
摘要:
Disclosed is a process for purifying 2,6-naphthalene dicarboxylic acid produced by disproportionation and more efficiently recycling byproduct dipotassium salts which includes the steps of: a) Contacting an aqueous solution containing the disalt of 2,6-NDA(2,6-K2NDA) with carbon dioxide to form as a precipitate the monopotassium salt of 2,6-NDA (KHNDA) and an aqueous solution containing 2,3-KHNDA, K2NDA, and potassium bicarbonate; b) Disproportionating said monopotassium salt (KHNDA) to form 2,6-NDA and an aqueous solution containing K2NDA, and potassium bicarbonate; c) Separating said 2,6-NDA and concentrating said aqueous solution containing K2NDA and potassium bicarbonate by reverse osmosis.
摘要:
Disclosed is an integrated process for producing 2,6-naphthalene dicarboxylicacid comprising oxidizing a methylnaphthalene feedstock, hydrodebrominating the crude naphthoic acid product under conditions different from any work known in the art, forming a potassium salt of the acid; disproportionating the potassium salt to produce 2,6 potassium salts of NDA; selectively precipitating K2NDA; selectively precipitating the monopotassium salt of 2,6 NDA(KHNDA); disproportionating the KHNDA into 2,6 NDA and K2NDA; further reacting the 2,6 NDA in a pipe reactor; and drying the product 2,6 NDA by conventional means or directly slurrying directly into a PEN process. The process can tolerate impurities in the economical methylnaphthalene feed and the resulting 2,6 NDA is of high quality with
摘要:
There is provided a method of removing metal residues from a polymer cement, the method comprising polymerizing a monomer with a metal-based polymerization initiator to give a polymer cement having metal polymerization initiator residue; adding an organic-soluble acid having a pKa no greater than about 4.5 to the polymer cement, thereby forming an acid containing organic phase; mixing the organic phase with an aqueous phase containing a mineral acid; and recovering the polymer cement substantially free of metal residue.
摘要:
A process for preparing a polymer cement which is relatively free of alkali metal salt by preparing the polymer cement with a polymerization terminating agent which is a diketone which leaves alkali metal salt in the cement which is readily removable by centrifugation.
摘要:
A process is provided comprising the steps of contacting a Group VIII metal hydrogenation catalyst residue containing polymer solution with from about 2 to about 50 parts by weight water based on 100 parts by weight of polymer solution, centrifuging the polymer from metal containing particles with a centrifugal force such that the centrifugal force times the time duration of centrifugation divided by the viscosity of the polymer solution equals or exceeds about 50 G-minutes/cp, and recovering a polymer solution comprising less than 10 ppm by weight, based on the polymer, of the Group VIII metal.
摘要:
In producing CO.sub.2 from subterranean reservoirs at conditions apt to cause both aqueous and CO.sub.2 -rich liquid phases to flow in pipes conveying the fluid, the formation of hydrates is prevented by adding a specified type of inorganic electrolyte hydrate inhibitor in proportions capable of maintaining an effective concentration within the aqueous liquid phase.
摘要:
A process for the removal of HCN from gaseous streams is described, the process being characterized by reaction of the HCN in the gaseous stream with an ammonium polysulfide solution, formation of ammonium thiocyanate in solution, decomposition of ammonium polysulfide and precipitation of sulfur from the ammonium thiocyanate solution in a stripping zone, and hydrolysis of the ammonium thiocyanate. Recycle or recovery of sulfur and hydrolysis products are contemplated.