Patent GB-615405-A (GB)
Title: Improvements in the manufacture of moulded products
IPC: C10L5/12
Filed: 1942-03-26
Abstract: Moulded products such as briquetted ores are obtained by mixing a pulverulent mass with a small proportion of a dispersing and wetting agent, water, 2-8 per cent of sodium silicate based on the weight of the mass, and an agent capable of decomposing the sodium silicate to form nascent silica.  The pulverulent mass may consist of any material which has no tendency to swell when wetted.  The dispersing agents which are preferably used in an amount of 2 per cent of the weight of the sodium silicate may be the condensation and sulphonation products of aromatic hydrocarbons and derivatives thereof, with aldehydes and alkyl-and aralkyl-naphthalene sulphonates; sulphonate derivatives from aliphatic substances, aliphatic alcohols, fatty acids and amides of said acids, amines and esters derived from fatty acids; sulphonation products of the distillation residues from benzaldehyde; the water soluble products obtained by reacting ethylene oxide on water-insoluble substances containing an active hydrogen atom and other insoluble substances; liquorice, saponine, hydrolysed albumens, and the residual liquors from the treatment of ligneous materials with sulphites.  The preferred catalytic agent is sodium fluosilicate, but any of the fluosilicates, fluotitanates or fluozirconates of sodium or potassium, or silica ground to an impalpable powder may be used.  In addition acid liberating substances such as bicarbonates and other carbonates which can be made to liberate carbon dioxide, aluminium sulphate, sulphides or ortho-or para-toluene sulphoxyl-chloride may be added.  In Example 5 powdered ores, such as those of lead, zinc and iron are agglomerated with the aid of a sodium silicate solution of 36 DEG  Be if the ores are dry, or of sodium silicate in the solid form if the ores are damp.ALSO:Moulded products are obtained by mixing a pulverulent mass may consist of any material dispersing and wetting agent, water, 2-8 per cent of sodium silicate based on the weight of the mass, and an agent capable of decomposing the sodium silicate to form nascent silica.  The pulverulent mass may consist of any material which has no tendency to swell when wetted.  The dispersing agents which are preferably used in an amount of 2 per cent of the weight of the sodium silicate, may be the condensation and sulphonation products of aromatic hydrocarbons and derivatives thereof, with aldehydes and alkyl-and aralkyl-naphthalene sulphonates; sulphonate derivatives from aliphatic substances, aliphatic alcohols, fatty acids and amides of said acids, amines and esters derived from fatty acids sulphonation products of the distillation residues from benzaldehyde; the water soluble products obtained by reacting ethylene oxide on waterinsoluble substances containing an active hydrogen atom, and other insoluble substances; liquorice, saponine, hydrolysed albumens, and the residual liquors from the treatment of ligneous materials with sulphites.  The preferred catalytic agent is sodium fluosilicate, but any of the fluosilicates, fluotitanates, fluotungstates or fluozirconates of sodium or potassium, or silica ground to an impalpable powder, or ashes may be used.  In addition acid liberating substances such as bicarbonates and other carbonates which can be made to liberate carbon dioxide, aluminium sulphate, sulphides or ortho- or para-toluene sulphoxyl-chloride may be added.  In examples coke dust, coal or anthracite is briquetted, the sodium silicate being in the form of a solution of 36 deg.  Be if the coke is dry, and in the solid form if the coke is damp.  The wetting agent used for coal is sodium butyl-naphthalene sulphonate.  In further examples powdered ores, such as those of lead zinc and iron, foundry sands, for use in the manufacture of foundry cores; and silica and zirconium fireclay for refractories are agglomerated by similar processes, glycols, glycerine, sawdust, balls of rice or other cereals being added to assist casting.  In another example graphite for use in the manufacture of electrodes, retorts, muffles and crucibles is pretreated by conversion to graphitic acid which is then heated to 1000 DEG  C. out of contact with air.