摘要:
A method is disclosed for immobilizing material contaminated with heavy metal ions, said metal ions in a liquid environment being allowed to react with a metal-complexing agent with the formation of a metal complex, the metal-complex formed being mixed, in the presence of water, with an inorganic, hydraulic binder comprising blast furnace slag cement, fly ash cement or a combination thereof to form a matrix having reductive properties in the form of a hard, rocklike material, which method is characterized in that said metal complex is formed in the presence of a metal-complex bond activator. Said metal-complex bond activator is preferably a water-soluble salt of a transition metal element, expediently ferric chloride or manganese sulphate. The invention also relates to a fixant for immobilizing heavy metal ions comprised in waste material.
摘要:
A body of carbonaceous or other material for use in corrosive environments such as oxidizing media or gaseous or liquid corrosive agents at elevated temperatures, in particular in molten salts such as cryolite, is coated with a protective surface coating which improves the resistance of the body to oxidation or corrosion and which may also enhance the bodies electrical conductivity and/or its electrochemical activity. The protective coating is applied in one or more layers from a colloidal slurry containing reactant or non-reactant substances, or a mixture of reactant and non-reactant substances, in particular mixtures containing silicon carbide and molybdenum silicide or silicon carbide and silicon nitride, which when the body is heated to a sufficient elevated temperature reaction sinter as a result of micropyretic reaction and/or sinter without reaction to form the protective coating.
摘要:
Composition propre à améliorer les propriétés rhéologiques des produits à base de ciments et notamment à augmenter la durée d'ouvrabilité des bétons prêts à l'empoi, caractérisée par le fait qu'elle comprend, sous la forme d'un mélange ternaire
un agent superplastifiant ou réducteur d'eau à effet dispersant, un agent stabilisant susceptible de former un chélate avec les ions calcium du produit à base de ciment, et un agent dispersant polycarboxylique polymère.
摘要:
Die Erfindung betrifft ein Mittel und ein Verfahren zur Herstellung einer Dichtwandmassen-Suspension, insbesondere für die Erstellung von Dichtungsschlitzwänden nach dem Einphasenverfahren auf der Basis von Bentonit, gemahlener Hochofenschlacke und Anreger für die Hochofenschlacke, wobei der Anreger für die Hochofenschlacke bis zum Anmachen der Suspension getrennt von der Trockenmischung, die im wesentlichen aus Bentonit und gemahlener Hochofenschlacke besteht, gehalten ist.
摘要:
Stable vermiculite dispersions which are substantially free of settling and a method of preparing them are provided: the dispersions are obtained by treating vermiculite crystals with an anionic non-citrate chelating agent. The anionic chelating agent enhances the rate and degree of swelling of the vermiculite in an aqueous medium. The swollen vermiculite is delaminated by shearing to provide the aqueous vermiculite dispersions of the invention.
摘要:
There are disclosed methods and compositions for retarding the room temperature gelation and eventual hardening of phenolic resole resins when such resins are mixed with lightburned magnesium oxide or magnesium hydroxide hardening agents with or without an ester functional hardening agent. Retardation of gelation and hardening is achieved by incorporating into said mixture a retarder compound such as one which decreases the solubility of magnesium in said mixture. Additionally, hardening at higher temperatures, thermal curing, coated abrasives, polymer concrete, and other methods and compositions of this invention are disclosed.
摘要:
Fluid compositions containing a silica-particle suspension with no intrinsic cementitious properties may be pumped into a wellbore. Upon making downhole contact with previously placed well cements from primary-cementing or previous remedial-cementing operations, the silica suspension reacts to form a gel that seals voids, cracks or fissures in the cement sheath. Portland cement is the preferred cement with which the silica-particle suspensions interact downhole.
摘要:
The present disclosure is related to a family of metals chelates for use as a hydrogen sulfide scavenger in asphalt, and the preparation thereof. The metal chelates, in particular amino acid metal chelates, are particularly efficient at reducing the hydrogen sulfide emissions of asphalt.
摘要:
An air void-forming agent, more particularly for cementitious systems, contains at least one air void-forming material with foaming effect, at least one air void-forming material with defoaming effect, and water.