摘要:
A passivation method for the metallic surface of a nickel and iron-based superalloy which is used as the constituent material of reactor or furnace walls is described, in which the superalloy is coated on at least one of its surfaces which comes into contact with a corrosive atmosphere containing either hydrocarbons at high temperature or containing oxidizing gases at high temperature, with at least two successive layers resulting from successive chemical vapour deposition of its one or more constituent elements, the external phase, resulting from chemical vapour deposition of at least one silicon compound and the layer(s) deposited between the superalloy surface, and the external layer resulting from chemical vapour deposition of at least one of a metal or metalloid.
摘要:
Coated steel articles are described which exhibit anti-coking properties, and a process for producing such articles by depositing an anti-coking coating on a matrix constituted by a steel, in general a refractory steel. These articles comprise: a refractory steel substrate comprising at least 0.2% by weight of carbon; a carbon-rich diffusion barrier; and an outer layer containing 90% to 99% by weight of chromium, coated by a cementation method. More particularly, the coated steel articles constitute tubes for reactors or stills used in various refining or petrochemical processes.
摘要:
A process for sequestrating carbon emitted into the atmosphere in the form of CO2 comprises: a) a step for concentrating CO2 in the liquid phase; b) a step for electro-reduction in an aprotic medium to a compound in which the carbon changes to oxidation number +3 in the form of oxalic acid or formic acid; c) if appropriate, a step for re-extracting oxalic or formic acid in the aqueous phase; and d) a step for mineralization by reaction with a compound of an element M, resulting in a stable compound in which the atomic ratio C/M is about 2/1.
摘要:
The invention concerns a method for manufacturing steel wire comprising the following steps: manufacturing a reinforcing wire of sizeable length by rolling or hot wire drawing from steel containing the following elements: 0.18% to 0.45 % C, 0.4% to 1.8% Mn, 1% to 4% Cr, 0.1% to 0.6% Si, 0% to 1.5% Mo, 0% to 1.5% Ni, at most 0.01% S and 0.02% P, the reinforcing wire having, after being rolled or hot drawn, a temperature at least higher than the AC3 temperature, preferably by 50 to 200° C. and in particular by 100 to 150° C.; winding the wire in reels before air cooling the raw manufacturing wire to obtain a HRC hardness not less than 40 and preferably higher than 45. In a variant, the method consists in quenching and tempering so that the wire has a hardness between 20 HRC and 35 HRC. The invention also concerns a reinforcing wire and a flexible tube for carrying effluents.
摘要:
An austenitic stainless steel with a composition comprising: at most 0.15% of C; 2% to 10% of Mn; at most 2% of Ni; at most 4% of Cu; 0.1% to 0.4% of N; 10% to 20% of Cr; at most 1% of Si; at most 3% of Mo; and at most 0.7% of Ti; is used to manufacture equipment, for example furnaces, reactors or ducts, or elements of this equipment, or to coat the internal walls of this equipment, said equipment being used to implement petrochemical processes conducted at temperatures of 350° C. to 1100° C. and in which coke can be formed.
摘要:
A process for the reversible storage of hydrogen, comprising bringing an alloy of alkaline metal and silicon into contact with gaseous hydrogen leading to the formation of the hydride or corresponding hydrides, comprises the use of at least one balanced system that corresponds to the formula: MXMSi MXMSiHn where M is selected from among Li, Na, or K and in which atomic ratios XM take on the following values: XLi=1 1≦XNa≦3 1≦XK≦2 n is the number of hydrogen atoms corresponding to the stoichiometry of the hydride or formed hydrides. or to the formula MSiXSi MSiXSiH2XSi+1 where M is selected from among Li, Na, or K and in which the atomic ratio XSi=Si/M takes on a value of 1 to 4.
摘要:
A process for the reversible storage of hydrogen, comprising bringing into contact a material that consists of magnesium elements and nitrogen elements with gaseous hydrogen leading to the formation of an amide or corresponding hydrides, comprises the use of a balanced system corresponding to the formula: Mg3N2Mg(NH2)2+2MgHn where n is the number of hydrogen atoms corresponding to the stoichiometry of the hydride or hydrides formed. The material can also comprise, in a minor proportion, at least one transition metal of groups 3 to 12 of the periodic table that is selected from among Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn and Pd.
摘要翻译:一种用于氢的可逆储存的方法,包括使由镁元素和氮元素组成的材料与导致形成酰胺或相应的氢化物的气态氢接触的材料包括使用对应于下式的平衡系统:Mg 3 N 2 “img id =”CUSTOM-CHARACTER-00001“he =”2.46mm“wi =”2.46mm“file =”US07608239-20091027-P00001.TIF“alt =”custom character“img-content =”character“img-format =“tif”/> Mg(NH 2)2 + 2MgHn其中n是与形成的氢化物或氢化物的化学计量相对应的氢原子数。 所述材料还可以以少量的比例包含选自Sc,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn中的至少一种元素周期表第3至12族的过渡金属和 钯
摘要:
A process for the reversible storage of hydrogen, comprising bringing into contact an alloy of magnesium and palladium with the gaseous hydrogen leading to the formation of hydride or corresponding hydrides, comprises the use of a balanced system corresponding to the formula: MgxPdMgxPdHn in which atomic ratio x takes on a value of 3 to 6, and n is the number of hydrogen atoms corresponding to the stoichiometry of the hydride or hydrides formed or to the formula: MgxPdMg2PdH4+Mgx-2Hn in which the atomic ratio x takes on a value of 7 to 9, and n is the number of hydrogen atoms corresponding to the stoichiometry of the hydride or hydrides formed.
摘要:
In order to produce elements for furnaces, reactors or conduits on the walls of which coke can appear, steels are used with a composition which is adapted to resist coking comprising, by weight, at most 0.25% of C, 1.5% to 5% of Si, 4% to 10% of Cr, 0.5% to 2% of Mo, 0.3% to 1% of Mn, at most 0.030% of S and at to most 0.03% of P, the complement to 100% being essentially iron. Novel steel compositions for use in these applications are those which comprise, by weight, at most 0.25% of C, more than 2.5% and up to 5% of Si, 4% to 10% of Cr, 0.5% to 2% of Mo, 0.3% to 1% of Mn, at most 0.03% of S and at most 0.03% of P, the complement to 100% being essentially iron.