摘要:
Stable aqueous suspensions of zeolite 4A which can be easily pumped, containing from 0.5 to 65% of zeolite and from 0.05 to 6 g (per 100 g of zeolite) of a suspending agent, composed of mixtures of ethoxylated alkanols, said mixtures being obtained by ethoxylating: a) biodegradable branched alkanols, having from 10 to 18 carbon atoms and having a single branching in position 2, said mixtures containing at least 2 alkanols having a different number of C atoms; or b) mixtures containing 40-100% of branched alkanols as in a) and 60-0% of linear alkanols having from 10 to 18 C atoms.
摘要:
Raw gaseous formaldehyde is purified by passing it through a first series of superimposed fluidized beds of solid adsorbent, maintained at 80.degree.-140.degree. C., while continuously circulating solid adsorbent from each bed to the underlying bed and discharging from the lowermost bed the spent adsorbent, delivering the latter to the uppermost bed of a second series of superimposed fluidized beds of solid adsorbent, passing through the latter a stream of inert gas to strip the adsorbed formaldehyde at 130.degree.-150.degree. C., while continuously circulating said spent adsorbent from each bed to the underlying bed and discharging from the lowermost bed the adsorbent thus treated, delivering the latter to the uppermost bed of a third series of fluidized beds of solid adsorbent, and passing through the latter a stream of inert gas to regenerate the adsorbent at 145.degree.-250.degree. C., while continuously circulating the adsorbent from each bed to the underlying bed, discharging the regenerated adsorbent from the lowermost bed and recycling said regenerated adsorbent to the uppermost bed of the first series.
摘要:
Process for the separation of trioxane from aqueous solutions containing it together with formaldehyde, which comprises subjecting the said solutions to evaporation at temperatures of 100.degree. C or lower, at pressures lower than atmospheric, and with residence times of less than 1 minute under the evaporation conditions, with vaporization of a quantity of from about 5 to about 15% by weight of the solution introduced, and recovering the trioxane from the products evaporated in this way.
摘要:
Polyformaldehyde is prepared by feeding anhydrous formaldehyde to a reaction medium containing a liquid organic diluent non-solvent for the polyformaldehyde and non-reactive towards the other constituents of the reaction medium, and containing in a dispersed form a copolymer A-B, whereinA is a polylactonic block of recurring units ##EQU1## B is a polylactamic block of recurring units ##EQU2## wherein PM.sub.1 and PM.sub.2 are linear polymethylene chains having from 2 to 13 and 3 to 13 carbon atoms, respectively.
摘要:
Polyformaldehyde is prepared by polymerizing anhydrous monomeric formaldehyde in an organic, liquid and inert diluent which is a non-solvent for polyformaldehyde, in the presence of a catalyst of the formula: ##STR1## wherein A.sup.(-) is a lactamate group: ##STR2## in which PM is a linear polymethylene chain with from 3 to 13 carbon atoms, possibly substituted with one or more alkyl, cycloalkyl, aryl or alkylaryl radicals, and wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently are an alkyl, cycloalkyl, aryl or alkylaryl radical.
摘要:
Formaldehyde present in a waste water containing lower carboxylic acids is recovered by reacting said waste water at 0.degree. to 90.degree. C. with the amount of ammonia required for converting said formaldehyde into hexamine and the latter is recovered in solid form by evaporating the resulting solution.The solid hexamine thus recovered has a content in lower carboxylic acids not exceeding 0.05 wt.%, is practically free from other impurities and is suited for any conventional use.
摘要:
A stabilized polymeric composition comprising an acetal polymer and as stabilizer a copolymer R--D--A--B--D--R, in which:A is a block of recurring units: ##EQU1## B is a block of recurring units: ##EQU2## D is a block of recurring units: ##EQU3## R is an ester, ether or urethane group wherein PM.sub.1 and PM.sub.2 are linear polymethylene chains having 2 to 13 and 3 to 13 carbon atoms, respectively, non substituted or having at least one hydrogen atom replaced by an alkyl, aryl, alkylaryl or cycloalkyl radical; the said stabilizer being used in a proportion of from 0.02 to 12 parts by weight to 100 parts by weight an acetal polymer.
摘要:
Process for the synthesis of ZMS-5 zeolites essentially consisting of: a. preparing two aqueous solutions of sodium aluminate and silicate; b. putting the two solutions in contact with each other under stirring at room temperature; c. adding a solution of a mineral acid to solution (a) or to solution (b) or to solution (a)+(b), in such a quantity that the molar ratio OH−/H2O ranges from 0.02 to 0.03; d. adding a quantity of water sufficient for maintaining fluid the reacting mixture and the molar ratio OH−/H2O from 0.017 to 0.022; e. pre-heating the final mixture obtained at the end of steps (a)-(d) at a temperature ranging from 20 to 60° C.; and f. heating the mixture, under stirring, at a temperature ranging from 100 to 200° C.
摘要:
A process for purifying a polymerisable monomer selected from the group consisting of cyclic ethers, hydrocarbon olefins, vinyl compounds, aldehydes, lactams of the formula: ##EQU1## wherein x is an integer from 3 to 13 and lactones of the formula: ##EQU2## wherein n is an integer of from 1 to 4 and wherein R represents an hydrogen atom, an alkyl group or an aryl group; said process comprising contacting a liquid consisting of said monomer at a temperature of not greater than 130.degree. centigrade and at a pressure sufficient to keep said monomer in liquid form, with a solid absorbent consisting essentially of a porous reticulated macromolecular alkali metal or alkaline earth metal salt of a cationic exchange resin containing carboxylic, sulfonic or phosphoric acid groups, said cationic exchange resin having a specific surface area of at least one square meter per gram and a pore diameter of from 10.sup.1.3 to 10.sup.5 angstroms and recovering the purified monomer.
摘要:
Composition of lubricating oil which comprises: a) a greater portion of synthetic lubricating component or a mixture of synthetic lubricating component and a mineral base for lubricating oils, the synthetic lubricating component being prepared by the oligomerization and subsequent hydrogenation and the possible removal of low-boiling by-products, of a composition of olefins basically consisting of: 1) a mixture of n-olefins having a content of olefins from C.sub.14 to C.sub.17, preferably from C.sub.15 to C.sub.16, of at least 80%, preferably greater than 85%, 2) alpha olefins from C.sub.15 to C.sub.17, preferably basically C.sub.16, the content of the alpha olefin (2) being from 5 to 25% by weight, preferably from 10 to 20%, with respect to the sum of (1)+(2).