摘要:
Arthropodicidally and fungicidally active heavy metal salts of nikkomicin are produced by reacting nikkomicin with a water-soluble heavy metal salt in an aqueous medium.
摘要:
A process for concentrating nikkomicins (X) and (Z) from a dilute impure aqueous solution thereof, comprising contacting the solution with a weakly basic ion exchanger and eluting the adsorbed material with an acid thereby to obtain a concentrated mixture of nikkomicin (X) and nikkomicin (Z). The dilute solution being treated can directly be a filtered microbial cultivation liquor or such a liquor can be prepurified by contact with an acid ion exchanger followed by elution with a base. The recovered material is of relatively high purity.
摘要:
The metallization of porous solid bodies, such as, for example, ion exchange materials, by loading the surfaces of the metal-free substrates with transition metal ions and subsequently treating them with reducing agents can be improved by activating the substrates, before or after the loading with metal ions, with elements of group 1 or 8 of the periodic table or compounds thereof and sensitizing any activating ions still present. The metallization products are useful hydrogenation catalysts.
摘要:
Cyclic N-vinylacylamines are prepared by heating carbonic acid esters of cyclic N-2-hydroxyethylacylamines in the presence of a catalytic amount of alkali or alkaline earth metal compound having an alkaline reaction and subsequently distilling the reaction mixture.Cyclic N-vinylacylamines are valuable precursors for preparing plant protection agents and medicaments and serve as polymerization and copolymerization components for preparing plastics, surface coatings, paints and ion exchange materials.
摘要:
The invention relate to a process for reducing the wash water required by weakly basic anion exchangers containing primary and/or secondary amino groups when fed with water containing carbon dioxide; in accordance with the process the exhausted, weakly basic anion exchangers are treated with dilute aqueous mineral acids before being regenerated.
摘要:
A process for the preparation of pure alkyl tertiary alkyl ethers and hydrocarbon raffinates which are substantially free from tertiary olefins and alkanols. An alkanol and a hydrocarbon mixture containing at least one tertiary olefin are contacted with the alkanol being present in a stoichiometric excess. The reaction product is removed from the reaction zone and excess alkanol in the reaction product or a partial stream thereof is absorbed on a synthetic ion exchanger containing groups which exchange cations or anions or mixtures of such ion exchangers. After absorption of at least a portion of the alkanol on the synthetic ion exchanger, the alkanol is desorbed by contacting the same with a hydrocarbon mixture containing at least one tertiary olefin.
摘要:
In the purification of acarbose by contacting an acarbose-containing solution with a cation exchanger to adsorb the acarbose, eluting the ion exchanger and collecting an eluate fraction enriched in purified acarbose, the improvement wherein the cation exchanger is a polymer obtained by polymerizing an aromatic compound possessing at least one vinyl group and at least one hydrophilic monomer in the presence of a solvent for the monomer which is a precipitant for the crosslinked polymer formed, isolating the resistant polymer, and sulphonating the polymer in the presence of a swelling agent for the polymer. The invention gives sharp separation and other processing advantages.
摘要:
A new method of diazotization consists in using as the diazotizing agent in an aqueous, aqueous organic or organic medium the system comprising salt of nitrous acid+acid insoluble in the reaction medium, in particular organic or inorganic cation exchangers having acid groups. The diazonium salt solutions thus prepared are immediately reacted with coupling components to give azo dyestuffs, the insoluble acid and/or its salt being separated off before or after the coupling.
摘要:
Stable, concentrated aqueous solutions of, in particular, anionic reactive dyestuffs are obtained in a comparatively simple manner by freeing from salts, preferably by means of membrane separation processes, solutions of these substances just as they are obtained in the course of synthesis, and by replacing, with the aid of ion exchangers, the cations which cause sparing solubility.
摘要:
New Synthetic resins useful as inert material for separating layers in ion exchanger mixed bed filters. The new synthetic resins are copolymers of(a) substituted styrenes and/or methacrylates,(b) methacrylates of polyhydric alcohols and/or aromatic polyvinyl compounds and(c) unsaturated hydrocarbons which have at least two allyl groupings in the molecule, and/or polyvinyl ethers of polyhydric alcohols, and optionally(d) styrene.