Patent classifications
C01D1/04
Sodium hydroxide production with carboxylic acid and sulfur dioxide intermediates
The present application pertains to processes producing oxides using a weak acid intermediate. In one embodiment a material comprising calcium carbonate is reacted with a solution comprising aqueous carboxylic acid to form a gas comprising carbon dioxide and a solution comprising aqueous calcium carboxylate. The solution comprising aqueous calcium carboxylate is reacted with sodium sulfate to form a solution comprising aqueous sodium carboxylate and a solid comprising calcium sulfate. The solution comprising aqueous sodium carboxylate is reacted with sulfur dioxide to form sodium sulfite and an aqueous carboxylic acid. The sodium sulfite is separated from said aqueous carboxylic acid and reacted to form a solid comprising calcium sulfite which is decomposed to form calcium oxide and sulfur dioxide.
METHODS OF REDUCING COLOR IN ALKANOLAMINE COMPOSITIONS AND COMPOSITIONS PRODUCED THEREBY
A method of reducing color in an alkanolamine, the method comprising: contacting the alkanolamine with an amount of an aqueous solution effective to provide 5 to 1000 parts per million by weight of an alkali metal borohydride, based on parts by weight of the alkanolamine; and 0.5 to 10,000 parts per million by weight of an alkali metal hydroxide, based on parts by weight of the alkanolamine; preferably wherein the color-reduced alkanolamine is not distilled after the contacting.
METHODS OF REDUCING COLOR IN ALKANOLAMINE COMPOSITIONS AND COMPOSITIONS PRODUCED THEREBY
A method of reducing color in an alkanolamine, the method comprising: contacting the alkanolamine with an amount of an aqueous solution effective to provide 5 to 1000 parts per million by weight of an alkali metal borohydride, based on parts by weight of the alkanolamine; and 0.5 to 10,000 parts per million by weight of an alkali metal hydroxide, based on parts by weight of the alkanolamine; preferably wherein the color-reduced alkanolamine is not distilled after the contacting.
SYSTEM AND METHOD OF REDUCING OXIDANTS IN A CHEMICAL STREAM
The invention is a system and method of reducing, reacting, and/or removing an oxidant or unwanted chemical species from a chemical stream. Particularly, the system and method include the use of one or more reductants that react with the undesired chemical species. The reductant and the chemical stream are added to a reactor and allowed to react for a desired amount of time. The reductant will reduce, react with, and/or remove the chemical species from the stream. The excess reductant and reaction products are then removed from the reactor, as described in more detail herein below.
SYSTEM AND METHOD OF REDUCING OXIDANTS IN A CHEMICAL STREAM
The invention is a system and method of reducing, reacting, and/or removing an oxidant or unwanted chemical species from a chemical stream. Particularly, the system and method include the use of one or more reductants that react with the undesired chemical species. The reductant and the chemical stream are added to a reactor and allowed to react for a desired amount of time. The reductant will reduce, react with, and/or remove the chemical species from the stream. The excess reductant and reaction products are then removed from the reactor, as described in more detail herein below.
Method for preparing 3-carbamoymethyl-5-methylhexanoic acid in recycling way
The present invention provides a method for recycling 3-carbamoylmethyl-5-methylhexanoic acid from 3-carba carbamoylmethyl moymethyl-5-methylhexanoic acid chiral resolving mother liquor. The method comprises the following steps: (a) distilling 3-carbamoylmethyl-5-methylhexanoic acid chiral resolving mother liquor, adding aromatic hydrocarbon, heating to dissolve, keeping the temperature and stirring; (b) after completing the reaction in step (a), cooling the reaction solution to 30-60 C., then adding alkali liquor dropwise, keeping the temperature and reacting; and (c) after completing the reaction in step (b), cooling the reactant to 20-30 C., layering, adjusting the pH of the separated water layer to 1 to 2, performing extraction by using an organic solvent, distilling an organic phase under a reduced pressure, and crystallizing at 05 C. to obtain 3-carbamoylmethyl-5-methylhexanoic acid. The method provided in the present invention is convenient to operate, and the recycled product is high in purity (99.8%) and yield.
Preparation method of 4-(4-amino-3-fluorophenoxy)-N-methylpyridine-2-formamide
The present invention relates to a preparation method of 4-(4-amino-3-fluorophenoxy)-N-methylpyridine-2-formamide capable of enabling 4-chlorine-N-methylpyridine-2-formamide to react with 4-amino-3-fluorophenol in the presence of an inorganic base. The present invention employs the inorganic base to replace potassium t-butoxide in the prior art, thus effectively solving the problem of a potential safety hazard of the potassium t-butoxide in industrial production. In addition, after the reaction is completed, the present invention employs a crystallization method for separation to obtain a reaction product; thus compared with the methods of extraction, concentration and column isolation and purification employed in the prior art, the present invention has a simpler operation and a lower cost, results in less environment pollution and a higher yield, and is very suitable for industrial production.
Preparation method of 4-(4-amino-3-fluorophenoxy)-N-methylpyridine-2-formamide
The present invention relates to a preparation method of 4-(4-amino-3-fluorophenoxy)-N-methylpyridine-2-formamide capable of enabling 4-chlorine-N-methylpyridine-2-formamide to react with 4-amino-3-fluorophenol in the presence of an inorganic base. The present invention employs the inorganic base to replace potassium t-butoxide in the prior art, thus effectively solving the problem of a potential safety hazard of the potassium t-butoxide in industrial production. In addition, after the reaction is completed, the present invention employs a crystallization method for separation to obtain a reaction product; thus compared with the methods of extraction, concentration and column isolation and purification employed in the prior art, the present invention has a simpler operation and a lower cost, results in less environment pollution and a higher yield, and is very suitable for industrial production.
Chemical solution production
Solution production devices, systems, and methods. The system includes a base portion configured to receive a vessel containing a liquid. Upon the base portion receiving the vessel, liquid is transferred from the vessel and into the base portion where it undergoes an electrochemical reaction to produce a cleaning solution. The cleaning solution is then circulated back into the vessel.
NOVEL PEROXIDE STABILIZERS
Methods for stabilizing one or more peroxide compounds in solution comprising adding to the solution an effective amount of at least one compound selected from the group comprising (i) cyclic carbonates; (ii) poly-phosphonic acid chelating agents and salts thereof, and alkaline pH adjusting agents with a pKb value of up to 3.0, wherein the w/w ratio of the poly-phosphonic acid chelating agent or salt thereof to alkali or alkaline earth metal hydroxide is from about 1:1 to about 50:1; and (iii) mixtures thereof. Also disclosed are solutions comprising the above compounds, uses of the above compounds to stabilize peroxide compounds in solutions, and compounds recited above for use as novel stabilizers.