400 results about "Hydrogen yield" patented technology

The present invention provides a method and system for efficiently producing hydrogen that can be supplied to a fuel cell. The method and system of the present invention produces hydrogen in a reforming reactor using a hydrocarbon stream and water vapor stream as reactants. The hydrogen produced is purified in a hydrogen separating membrane to form a retentate stream and purified hydrogen stream. The purified hydrogen can then be fed to a fuel cell where electrical energy is produced and a fuel cell exhaust stream containing water vapor and oxygen depleted air is emitted. In one embodiment of the present invention, a means and method is provided for recycling a portion of the retentate stream to the reforming reactor for increased hydrogen yields. In another embodiment, a combustor is provided for combusting a second portion of the retentate stream to provide heat to the reforming reaction or other reactants. In a preferred embodiment, the combustion is carried out in the presence of at least a portion of the oxygen depleted air stream from the fuel cell. Thus, the system and method of the present invention advantageously uses products generated from the system to enhance the overall efficiency of the system.

The invention discloses a method by adopting biomass fast pyrolysis oil which carries out two sections of fixed bed reactors and water vapor catalytic reforming for producing hydrogen; the two sections of fixed bed reactors are connected in series, the natural dolomite which is relatively cheap and easily available is taken as catalyst in water vapor reforming reaction at the first section of fixed bed reactor, while the second fixed bed reactor adopts Ni/Mgo as catalyst to further improve the purity and yield of the target product gas. Comparatively high temperature and comparatively high S/C (more than 12) are extremely important for the effective transformation of the biomass pyrolysis oil in the first fixed bed reactor. However, for any temperature point, low mass space velocity can facilitate the increasing of the yield of any gas product and the total gas phase transformation ratio of the biomass oil is increased accordingly. The Ni/MgO catalyst is extremely effective in the purification stage, when S/CH4 is not less than 2 and the temperature is not lower than 800 DEG C, the transformation ratio of methane can reach 100 %. Low mass space velocity can facilitate effective transformation of methane; when mass space velocity is not higher than 3600h<-1>, the potential hydrogen yield can reach 81.1%.

The invention discloses a method of hydrogen production of biological cascade utilization on organic wastewater and relates to a method of producing hydrogen. The invention solves the existing problem of low conversion on biological hydrogen production with organic wastewater fermentation by using anaerobic activated sludge. The hydrogen production method of the invention is carried out as follows: firstly an anode chamber is in the anaerobic condition during startup procedure, anaerobic activated sludge is put into the anode chamber, the nutrient solution with pH value of 6.8 to 7.0 is introduced into the anode chamber, phosphate buffer is added into a cathode chamber, aeration is carried out in the cathode chamber in the previous 28 to 35 days of the startup procedure, startup is successful till the output voltage is continuously and steadily over 400 mV; secondly the organic wastewater is filled into the anode chamber from an inlet of the anode chamber and the organic wastewater is processed in the anode chamber, consequently hydrogen is obtained in the cathode chamber. The coulombic efficiency of the organic substrate conversion of the method reaches as high as over 80 percent, the electron transfer efficiency of transferring the cathode electron into hydrogen approaches to 100 percent, the purity of the hydrogen obtained in the cathode chamber in the entire process reaches 99.5 percent, the energy conversion efficiency of the entire process reaches over 80 percent, and the hydrogen yield calculated based on the input voltage is 288 percent.

The invention discloses a method for recycling and reusing all components of an LED-MOCVD (Light Emitting Diode-Metal Organic Chemical Vapor Deposition) preparation process tail gas through pressure swing adsorption in a whole temperature process. The method comprises procedures of pretreatment, medium-temperature pressure swing adsorption concentration, variable-temperature adsorption purification, pressure swing adsorption (PSA) hydrogen refining, hydrogen purification, condensation, freezing or ammonia gas distillation, liquid ammonia gasification, pressure swing adsorption ammonia extraction and ammonia gas purification, and hydrogen or ammonia-containing waste gases of the LED-MOCVD preparation process are purified till standards of electron-scale hydrogen (of which the purity is greater than or equal to 99.99999%v/v) and an electron-scale ammonia gas (of which the purity is greater than or equal to 99.99999%v/v) used in the LED-MOCVD preparation process, then recycling and reuseof waste gases are achieved, the hydrogen yield is greater than or equal to 75-86%, and the ammonia gas yield is greater than or equal to 70-85%. By adopting the method, the technical difficulty thata normal-pressure or low-pressure waste gas in the LED-MOCVD preparation process cannot be recycled or reused in the LED-MOCVD preparation process can be solved, and blanks of green and circular economic development of the LED industry can be made up.

The invention discloses a nickel-based catalyst for hydrogen production by ethanol steam reforming and a preparation method thereof. The catalyst is made by taking nanoporous silicon dioxide aerogel as a catalyst carrier, a metal elementary substance nickel nanowire as an active component, and nano-particles of MgO or CaO or ZrO2 or TiO2 or CeO2 or compound nano-particles thereof as an adjuvant. The preparation method comprises the following steps: preparing a sol from silanolate, an alcohol solvent, nickel nitrate or magnesium nitrate or calcium nitrate or zirconium nitrate or cerous nitrate or complex nitrate thereof and an acidic catalyst at certain proportions; forming a wet gel complex, and then performing supercritical fluid drying. The catalyst has strong catalytic activity and selectivity for the hydrogen production by the ethanol steam reforming, has higher hydrogen yield and stronger CO2 selectivity at a lower temperature, and limits the selectivity of byproducts CH4 and CO at a lower level. Meanwhile, the preparation method has simple process, low cost and certain mechanical strength.

The invention discloses a TiO2/BiVO4 photo-anode material which comprises a substrate, a TiO2 nano-rod array perpendicularly grown on the surface of the substrate, and a BiVO4 nano-particle layer deposited on the surface of the TiO2 nano-rod array. Through adoption of the TiO2/BiVO4 photo-anode material, the water photoelectrolysis property is improved; compared with other water photoelectrolysis materials, the TiO2/BiVO4 photo-anode material effectively overcomes the lattice defect of an interface layer, reduces the composition of photo-generated electrons and hole pairs, improves the own stability, expands the absorption spectrum range of visible light, promotes the effective separation of the photo-generated electrons and the hole pairs, realizes the synchronous reaction of hydrogen production and oxygen production, ensures that the ratio of the hydrogen yield to the oxygen yield is close to 2: 1, and is a relatively ideal water photoelectrolysis material. Moreover, the invention further discloses a preparation method of the TiO2/BiVO4 photo-anode material. The preparation method has the characteristics that the nano-structure control is easy to realize technically, the prepared binary nano-rod array is excellent in crystallization property, and the interface quality is relatively high.

The invention discloses a reaction device for making hydrogen with sodium borohydride and a method thereof. The device comprises a reaction device and a control device. A micro-processing unit of the control device is electrically connected with an analog-digital converting circuit, a keyboard, an LCD display screen, a radiator and an isolation drive circuit respectively; the analog-digital converting circuit is electrically connected with a hydrogen sensor, a pressure sensor and a thermistor respectively; the isolation drive circuit is electrically connected with a low-power hydraulic pump and a high-speed solenoid valve respectively; one pressure sensor, one thermistor and the hydrogen sensor are positioned on a reaction chamber. With regard to the method for making the hydrogen with the sodium borohydride, the low-power hydraulic pump is adopted to control the reaction speed and the hydrogen yield by automatically regulating the flow of the sodium borohydride solution which is added to the reaction chamber and according to reaction conditions. The device for making the hydrogen with the sodium borohydride has the advantages of high reaction efficiency in making the hydrogen, high automation degree, being easy to control the reaction speed, being safe and reliable in use, convenient and simple operation, and the like; and is especially suitable for supplying hydrogen source in a movable manner.

The invention discloses a preparation method of TiO2 nanotubes, which comprises the following steps: an appropriate amount of sodium titanate nanotubes obtained by a hydrothermal synthesis method is dispensed to be fully dipped in mixed solution of ammonium fluorotitanate and boric acid with the filtered molar concentration ratio of 1:1-1:5 for deposition with the deposition time of 10-120mins; the mixed solution is reacted to obtain the sodium titanate nanotubes with TiO2 films formed which are then dried in an oven and next treated with heat treatment in a muffle furnace and cooled naturally so as to obtain the anatase type TiO2 nanotubes. The TiO2 nanotubes prepared by the method has anatase crystal form and relatively high catalytic activity, so the hydrogen yield of photocatalysis hydrogen production can be increased and the photoelectric transformation efficiency of dye-sensitized solar cells can be improved.

The invention discloses a low-energy-consumption high-yield method for preparing hydrogen from raw gas. The method comprises the following procedures: pre-cleaning; naphthalene removal; transformationand desulfurization; sulfur recovery; refined debenzolization; pressure swing adsorption for hydrogen production; recovery of tail gas; nitrogen production; etc. After pretreatment and naphthalene removal, raw gas is allowed to enter the procedure of transformation and desulfurization so as to obtain more hydrogen and increase the yield of hydrogen, and then desulfurization is carried out in a desulfurization tower; then pure hydrogen is prepared through the procedure of refined debenzolization and the procedure of pressure swing adsorption for hydrogen production; through the procedures of tail gas recovery and nitrogen production, effective hydrogen in desorbed gas is recovered, and hydrogen yield is further increased; and pure nitrogen with a purity of 99% or more is further prepared through a nitrogen production unit. The method provided by the invention substantially reduces the energy consumption of an apparatus for hydrogen production from raw gas, increases hydrogen yield, recovers almost all the effective hydrogen component in the desorbed gas, realizes recovery and graded utilization of each component in the raw gas while guaranteeing low energy consumption and high yield, and by-produces sulfur, pure nitrogen and the other products while preparing pure hydrogen.

The invention belongs to a rare earth micro nano composite hydrogen manufacturing material, in particular to an aluminum-rare earth micro nano composite hydrogen manufacturing material. The existing material for manufacturing hydrogen by hydrolysis has the defects that after reacting with water, the surface of Al is formed with a compact oxide film, the hydrogen manufacturing reaction is not complete, the reaction rate is slow, the synthesizing process is complicated and the production cost is high. The aluminum-rare earth micro nano composite hydrogen manufacturing material of the invention is prepared from aluminum and rare-earth metal. The preparation method of the hydrogen manufacturing material has the following steps: adding aluminum powder, metal powder and salt into a stainless steel ball milling pot; adding absolute ethyl alcohol, adding the rare-earth metal powder under the protection of argon gas to seal the opening of the pot; placing the stainless steel pot on a planetary ball mill for ball milling for 1-2 hours, wherein the ratio of grinding media to material is 1:10-100, and the rotate speed is 300-600 revolutions per minute; and preparing the aluminum-rare earth micro nano composite hydrogen manufacturing material. The invention has the advantages that the preparation process is simple, no environmental pollution exists in the process of preparation; the hydrogen manufacturing material has small grain diameter, large specific surface area and high chemical activity; the hydrogen yield is high; and the raw materials has rich resources, low price and easy obtainment.

The invention discloses a method for producing hydrogen from biogas biomass. The method comprises the following four major procedures: pre-purification, concentration, hydrogen production and hydrogenextraction. After biogas has undergone pre-purification and desulfurization, the biogas is pressurized and enters the pressure-swing adsorption and concentration unit, and methane is concentrated; after pressurization and preheating, further desulfurization is performed in virtue of a fine desulfurization tower; intermediate gas obtained after fine desulfurization and process steam are further preheated and then enter a reformer, and methane reacts with water vapor to produce CO, CO2, and H2; waste heat produced by reforming can by-produce steam which is output; CO is converted into CO2 through multiple-stage heat recovery and medium-temperature conversion so as to obtain more hydrogen and increase hydrogen yield; converted gas enters the pressure-swing adsorption hydrogen extraction procedure after multiple-stage heat recovery and cooling so as to obtain pure hydrogen and produce by-products such as steam and sulfur. In concentration of methane in the concentration procedure, the once-through yield of methane can reach 95% or more; remaining effective components provide equipment with heat energy through the recycling of tail gas; so the total utilization rate of methane is almost 100%, and full recovery of methane is realized.

The invention provides an application of a three-dimensional ordered macro-porous perovskite type oxide which is used as an oxygen carrier for preparing hydrogen through a carbonic fuel chemical chain. The three-dimensional ordered macro-porous perovskite type oxide has the characteristics of the perovskite type oxide and has a three-dimensional ordered macro-porous structure of an inverse opal structure. The three-dimensional ordered macro-porous perovskite type oxide is used as an oxygen carrier for preparing the hydrogen through the carbonic fuel chemical chain and has a general formula of ABO3, wherein A is rare-earth metal and B is transition metal. The three-dimensional ordered macro-porous structured perovskite structure has stable properties and longer service life; pore channels and specific surface area are bigger; during a contact process of the oxygen carrier and a carbonic fuel, much more lattice oxygen for participating in reaction can be supplied; the contact of the oxygen carrier and the carbonic fuel can be boosted; the specific surface area of the oxygen carrier can be increased by abundant pore channels; catalytic conversion between small particles and gas molecules is boosted; the three-dimensional ordered macro-porous perovskite type oxide has higher reaction activity in chemical chain combustion and steam pyrolytic decomposition; and compared with the conventional metal oxygen carrier, the three-dimensional ordered macro-porous perovskite type oxide has higher reaction activity and hydrogen yield.

The invention discloses a cobalt-based MOFs material. The cobalt-based MOFs material is formed by cobalt-nitrate hexahydrate which is reacted with terephthalic acid through a hydrothermal method, andthen is washed and dried through N, N-dimethyl formamide and an absolute ethyl alcohol solvent. A preparation method comprises the following steps: firstly, adding cobalt-nitrate hexahydrate in absolute ethyl alcohol, and performing magnetic stirring, so as to obtain a clear cobalt nitrate solution, adding terephthalic acid in N, N-dimethyl formamide, and performing magnetic stirring, so as to obtain clear a terephthalic acid solution, and performing mixed ultrasonic treatment on the two solutions; secondly, loading the solution subjected to mixed ultrasonic treatment into a reaction kettle, and arranging the reaction kettle into an oven, ensuring that the solution is reacted under a certain condition, and filtering, washing and drying a reaction product in certain condition after the reaction, so as to obtain the cobalt-based MOFs material. When the material is applied to the catalysis of hydrolysis of sodium borohydride, the hydrolysis speed reaches 1700 to 2400 mL min-1g-1, and thecatalytic performance keeps 47 to 50 percent of the original hydrogen yield after circulation. The material has excellent catalytic performance, and has a wide application prospect in the field of thepreparation of new energy resources.

The invention discloses a CdS/MoO3 composite photocatalyst and a preparation method thereof, which relate to a catalyst material and a preparation method thereof. The catalyst solves the problems that the conventional hydrogen production by utilizing the light to decompose H2O is low in catalyst activity and hydrogen yield under visible light and cannot degrade organic pollutants. The CdS/MoO3 composite photocatalyst is prepared from Cd(Ac)2.2H2O, (NH4)6Mo7O24.4H2O and thioacetamide. The preparation method comprises the steps of: adding the Cd(Ac)2.2H2O, the (NH4)6Mo7O24.4H2O and the thioacetamide into solution of acetone or ethanol, sealing the obtained solution, then placing the obtained solution into an ultrasonic reactor to react, then cooling a product to room temperature, and then washing and drying to obtain the CdS/MoO3 composite photocatalyst. The composite photocatalyst is of nanosphere shapes, the particle size of the nanospheres is between 300 and 350nm, the composite photocatalyst is obtained by the self-assembling of each small particle with the particle size of between 5 and 20nm, and additionally, CdS nanocrystals are uniformly embedded in the nanospheres; and the catalyst is high in catalytic activity, and the hydrogen production rate can reach 2 to 5.25mmol/h.

The parallel flow catalyst reforming process with multiple movable bed reactors includes: making material oil flow from the first movable bed reactor to the last one successively for the material oil to contact with the reforming catalyst in different reactors, separating the reformed oil in subsequent separator, regenerating catalyst out of the second movable bed reactor through the last one, separating the regenerated catalyst into several parts, and feeding the first part to the first reactor and the last reactor successively while feeding the other parts to the second reactor through the last reactor but one separately. The said process has raised liquid product yield and hydrogen yield.

The invention discloses a carbon nano tube supported nickel catalyst as well as a preparation method and application thereof. The carbon nano tube supported nickel catalyst consists of 10-35% mass percentage content of nickel and 65-90% mass percentage content of carbon nano tube. The catalyst of the invention vastly reduces the energy consumption during bio-oil hydrogen production, and improves the bio-oil conversion rate, hydrogen yield and the catalyst service life by the synergy of the active constituent, being favorable for realizing biomass fast pyrolysis bio-oil preparing technology and reforming bio-oil hydrogen production technology integration.

The invention provides an integral catalyst for biological oil steam reforming hydrogen production, which has high reaction activity, strong carbon deposition resistance and good stability, and further provides a preparation method and application thereof. The catalyst consists of a carrier and an active component and comprises the following components by weight percentage: 5-20wt percent of active component nickel oxide, 0-5wt percent of alkali metal auxiliary agent, 0-5wt percent of metal auxiliary agent and the balance of integral ceramic carrier with the surface coated with 1-5 percent of Gamma-Al2O3. The integral catalyst is applied to biological oil reforming hydrogen production and has the characteristics of simple preparation method, easy control of conditions and good catalyst repeatability. Compared with the common granular type catalyst, the integral catalyst has the characteristics of more even heating, less mass transfer resistance, has higher activity to reaction, strong carbon deposition resistance and good stability, and greatly improves the biological oil conversion rate, hydrogen yield and catalyst service life.

The invention relates to nano-iron-loaded biochar, a preparation method of the nano-iron-loaded biochar, and an application of the nano-iron-loaded biochar in a dark fermentation hydrogen production process. Ferrite and soluble starch are taken as raw materials which are subjected to reaction under proper conditions and are dried and charred to obtain the nano-iron-loaded biochar, wherein the maincomponent of the nano-iron-loaded biochar is Fe2O3/C, and the particle diameter range of the nano-iron-loaded biochar is 2-150nm. The biochar is of an amorphous structure, and Fe2O3 is of a mesoporous structure. By adding the iron-loaded biochar to an anaerobic fermentation system, a synergistic strengthening effect of iron and biochar in the dark fermentation hydrogen production process is realized, so that the hydrogen yield and the process stability are improved. Fe2O3 can not only release iron ions to enhance the activity of fermentative hydrogen producing bacterium hydrogenase but also increase the transfer rate of electrons; and furthermore, the biochar in nano-particles can enrich microorganisms, improve the concentration of hydrogen producing bacteria, buffer acid accumulation andrelieve ammonia inhibition.

The invention relates to a method for preparing hydrogen from cellulose. In the method, a reaction is performed under the hydrothermal conditions of a lower temperature of between 180 and 320 DEG C and lower pressure of between 1 and 20MPa, wherein the process mainly comprises cellulose hydrolysis and hydrothermal reforming of a hydrolysis product; the cellulose hydrolysis is catalyzed by H+ produced through reversible ionization of extra water soluble Bronsted acid, water soluble Lewis acid, solid acid or water; a metal catalyst consists of an active ingredient and a carrier; the active ingredient of the metal catalyst is one or more of Pt, Pd, Ni, Co, Ir, Ru and Rh and accounts for 2 to 10 weight percent of the total amount of the catalyst; and the catalyst is prepared by a chemical reducing method or an immersion method. The method has the advantages of simple equipment, single reactor, no need of special equipment, relatively mild reaction conditions and high product hydrogen yield (20.3mmol/g cellulose) and selectivity and is easy to operate.

The invention relates to a supported nanometer nickel catalyst, which adopts isopyknic impregnation method and loads active metal components on the carrier, with the active metal content from 0.1 percent to 5 percent. And then the active metal induces the metal nickel in nickel and phosphorus bath to deposit to yield high activity supported nanometer nickel catalyst with 15 percent content of active component nickel. The catalyst used to prepare 2, 5-dichloroaniline from chloronitrophen added with hydrogen yields high hydrogen activity. Especially when UCZHJ is used a reaction promoter, the reaction yield reaches 100 percent, and the catalyst can be used repeatedly.

A method for the non-oxidative conversion of methane into hydrogen, in addition to C₂ and higher hydrocarbons is disclosed. Pure methane is irradiated in a reaction zone which involves the multi-photon dissociation of methane under the influence of ultra-violet laser radiation at about 193 to about 400 nm, at room temperature and at a pressure ranging from 0.5 to 4 atmospheres. The products generated as a result of methane conversion are hydrogen and higher hydrocarbons which include ethane, ethylene, propane, propylene and isobutene. A conversion of 7-10% was achieved. The hydrogen yield achieved in one hour exposure of methane at ambient temperature and one atmosphere of pressure was 6.6 mole %.