Binders and inert refractory inorganic oxides can include naturally occurring clays, calcium sulfate, silicas, titanias, aluminosilicates, aluminates, zeolites and the like. 7 Is the salt zinc acidic or basic in nature? These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc. We also use third-party cookies that help us analyze and understand how you use this website. Zinc oxide is an amphoteric oxide that is insoluble in water. The sample is scanned from 5 to 70 degrees 2. Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet. ); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY, Owner name: 2021 The Master Chemistry. Zinc oxide reacts with hydrochloric acid to form zinc chloride and water. One such class of materials was described by Gangwal et al. Which bases are called alkali? The process of any of claims 6-16, wherein all or part of the alkali metal hydroxide is replaced with an alkali metal carbonate. Typically, the calcining temperature exceeds 300 C., and is preferably a temperature exceeding 500 C., more preferably 600 C. or higher. Typically, the slurry containing the intermediates which is used for spray drying, has 75 to 90 weight percent weight loss on ignition at a temperature of 500 C. or greater. This is because alkalis have a pH of greater than seven and can therefore ionize in an aqueous environment, allowing them to react with other substances such as H20 molecules. Included with the highly-mixed precipitated phases are the soluble alkali metal salts that are formed during the precipitation process. Understanding the difference between the two is important for understanding chemical reactions and the behavior of different compounds. These precipitated zinc oxide precursors and precipitated alumina precursors are prepared by precipitating nitrates, sulfates, chlorides, acetates, alkoxides, and like salts of zinc and aluminum with alkali metal hydroxides and carbonates as is well known to those skilled in the art. The slurry was then spray dried using conventional processes and apparatus to form substantially spherical spray dried particles. The use of co-precipitation techniques, promotes enhanced mixing and uniform distribution of the final sorbent components, and additionally promotes formation of small crystallite phases in the final sorbent product. There are many bases that are insoluble-they are not dissolving in water. Alkali is a subset of the base. Zinc Sulphate is acidic. 12. On adding alkali to acid the pH of the mixture increase. Even so, we define their concentration using hydroxide ions (OH), not pH. 6,951,635. 10. Zinc oxide is a base, because it reacts with an acid to form a salt and water. Preferably, the total dry solids content of such materials, based on adjusted weight, is less than about 25 wt %, more preferably less than about 20 wt %, even more preferably less than about 10 wt %, most preferably, less than about 5 wt %. These precipitated zinc oxide precursors and precipitated alumina precursors included, for example, hydroxides. Unless expressly stated otherwise, all weight percentages are calculated and expressed based on the adjusted weight of the sorbent components and compositions. All publications, patents, and patent applications cited in this specification are herein incorporated by reference as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Zinc oxide reacts with hydrochloric acid to form zinc chloride and water. Yes, an alkali is a base. . The active zinc component is a two-phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl 2 O 4 ) phase. All alkalis are bases. Neutralization is a reaction in which removal of alkalinity or acidity occurs. Necessary cookies are absolutely essential for the website to function properly. For the sorbent generated by U.S. Pat. No. Alkali and base are two important concepts in chemistry that are often used interchangeably, but they have distinct properties. This means that an Alkaline substance will have a higher concentration of Hydrogen ions compared to another compound. Menu Zinc Hydroxide is a weak base. To know differences between other topics in chemistry you can register to BYJUs or download our app for simple and interesting content. said active zinc component having a total zinc oxide content, calculated based on the combined zinc oxide of said zinc oxide phase and said zinc aluminate phase, of from about 50 wt %, to about 80 wt %, based on the weight of said active zinc component, wherein the residual sodium level in the solid phase is in the range of between 25 parts per million by weight of sodium and 2500 parts per million by weight of sodium. There are multiple definitions of the base. 27. Small amounts of these salts remain after the precipitation liquor is removed. They are feeling soapy, sour and corrosive. Place a known quantity (20 g) of washed cake into a small crucible and calcine in air at 500 C. for 2 hours and weigh the collected sample (g). The cookie is used to store the user consent for the cookies in the category "Analytics". Accordingly, this process allows small amounts of zinc oxide to be highly dispersed throughout the sorbent, providing high reactivity. For ease of discussion and clarity of disclosure, the sorbent compositions disclosed and discussed hereinafter shall be assumed to be free of promoter and inert components, except where stated to the contrary. In the coprecipitation method using alkali metal hydroxides or carbonates, and in contrast to the disclosure of Gangwal et al. Advantageously, the process comprises the steps of forming a slurry from the washed cake which comprises a precipitated intermediate of zinc oxide and a precipitated intermediate of aluminum oxide, and spray drying the slurry to form substantially spherical particles. Zinc Oxide is an Amphoteric Oxide (a molecule or ion that can react both as an acid as well as a base is called amphoteric. In addition, the high surface area and preferred uniform mixing of the precursors allows the formation of zinc aluminate using less harsh calcinations conditions than are required by conventional zinc aluminate forming processes which involve a solid-state reaction between alumina and zinc oxide. National Institutes of Health. RESEARCH TRIANGLE INSTITUTE, NORTH CAROLINA, Free format text: Heat the water to 50-70 C. Turn on both peristaltic pumps simultaneously. Zinc oxide based sorbents using alkali metal hydroxides and processes for preparing and using same, Application filed by Research Triangle Institute, Assigned to UNITED STATES DEPARTMENT OF ENERGY. This website uses cookies to improve your experience while you navigate through the website. 4. Your Mobile number and Email id will not be published. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims. Test your knowledge on difference between alkali and base! Set initial inside and outside temperatures to 320 C. and 125 C., respectively, Nozzle-08; pressure 0.75 bar, flow 25-35%. Are alkali and base the same? Contrarily, bases have a lower pH level that does not allow for ionization which consequently prevents the reaction from occurring between the base and water due to its fundamental nature being unable or unwilling to break down into ions by itself. Zinc oxide (when it is slightly dissoved in water) is a base but ALSO an acid, though very weak. is zinc oxide a base or alkalimark giangreco cheryl burton video. 11. It is a base that dissolves in water. Such preferred process embodiments can be achieved, as a result, at least in part, of the high reactivity, and high attrition resistance of the zinc oxide-based sorbents of the current disclosure. It depends on whether the substance ionizes or does not ionization upon contact with water respectively. No. These cookies track visitors across websites and collect information to provide customized ads. separating the liquid phase of the first slurry from the solid phase by a separating means; washing the filtered solid phase with water, preferably deionized water, to achieve a residual sodium level in the solid phase of between 25 parts per million by weight of sodium and 2500 parts per million by weight of sodium; treating the separated solid material from the first slurry with water and concentrated acid to generate a second slurry wherein the pH of the second slurry is adjusted with acid to be between 3.5 and 5.0; spray drying the second slurry to form spray dried particles; and. The process of any of claims 6-22, wherein the pH range of the second slurry is adjusted to be between 4.0 and 4.5. This is very important to remember- Not all bases are alkali but all alkali is base. In this blog post, we will discuss the Difference Between Alkali and Base to help you understand more about these two substances and how they work together in chemistry experiments. Ans: The word, free caustic al-kali, is usually defined as free NaOH; while total free alkali includes free caustic al-kali and additional alkaline sub-stances other than soap, mainly sodium carbonate and silicate. EUR 36,94 . pH & conductivity meter, model: HACH, HQ40d, Two Masterflex L/S with Easy-Load II peristaltic pumps, Weigh the metal salts (amount list in the table) and place them in a 4 L beaker. Continue to stir and maintain temperature of the precipitated mixture between 50 and 70 C. for another 30 min. Metals Zinc, Tin, Lead, Aluminium, Beryllium form amphoteric oxides or hydroxides). The process of claim 15, wherein said additional material is present in amount selected to provide fluidizable, attrition resistant, active zinc oxide containing sorbent particles containing at least about 95 wt% of said two-phase component consisting essentially of a zinc oxide phase and a zinc aluminate phase. Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limits of that range is also specifically disclosed. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS, Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof, Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material, Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising oxides or hydroxides of metals not provided for in group B01J20/04, Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising oxides or hydroxides of metals not provided for in group B01J20/04 comprising aluminium oxide or hydroxide; comprising bauxite, Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. The sorbents contain an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. No, not all bases are alkalis. The process of any of claims 6-8, wherein the active zinc oxide containing sorbent particles comprise zinc oxide grains about 12 nm to about 30 nm diameter. Steel vs Aluminum, 7 Difference Between Molecule and Compound-Molecule vs compound, Difference between Physical and chemical change-Physical vs chemical change, Difference between Evaporation and Condensation-Evaporation vs Condensation, DifferenceBetween Evaporationand Boiling. 8 Which is more acidic zinc sulphate or zinc hydroxide? Zinc oxide (when it is slightly dissoved in water) is a base but ALSO an acid, though very weak. Throughout the present specification, the terms about and/or approximately may be used in conjunction with numerical values and/or ranges. These inflection points were also present when the logarithm of the metal concentration was plotted against pH. 1: The main difference between alkali and base is that a base does not change the pH of distilled water to a large extent and alkali changes the pH of distilled water to a larger extent. The process of any of claims 6-28, wherein said spray dried particles are calcined at about 500C to about 900C. Calcine the spray dried powder in flowing air for two hours. The process of any of claims 6-8, wherein the active zinc oxide containing sorbent particles comprise zinc oxide grains less than 50 nm diameter. This disclosure relates to zinc-oxide-based sorbents, and to the processes for preparing and using these sorbents. The rare-earth elements (REE), also called the rare-earth metals or in context rare-earth oxides, and sometimes the lanthanides (yttrium and scandium are usually included as rare earths), are a set of 17 nearly-indistinguishable lustrous silvery-white soft heavy metals. But amphoteric oxides react with both acids and alkalis to form salts. National Center for Biotechnology Information. Alkalis are compounds that produce hydroxide ions in water, such as sodium hydroxide (NaOH) or potassium hydroxide (KOH). 23. density, crush strength, Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their form, Processes for preparing, regenerating, or reactivating, Thermal treatment, e.g. For purposes of these calculations, the zinc aluminate phase, ZnAl. Filter the precipitate using either a pressure filter or a vacuum filter, Wash the precipitate with DI water until the sodium levels are in the desired range. calcining or pyrolizing, Chemical treatments not covered by groups B01J20/3007 - B01J20/3078, Catalysts, in general, characterised by their form or physical properties, Catalysts containing parts with different compositions, Adsorbents used in seperation treatment of gases and vapours, Metals or metal compounds not provided for in B01D2253/104 or B01D2253/106, Linear dimensions, e.g. ZnO reacts with hydrochloric acid forming zinc chloride and water. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS, Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof, Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material, Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising oxides or hydroxides of metals not provided for in group B01J20/04, Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. The article a and an are used herein to refer to one or more than one (i.e., to at least one) of the grammatical object(s) of the article. 6,951,635 were successful and generated effective materials for the desulfurization of warm gases, the process for the generation of these sorbents involved the use of an ammonium hydroxide solution to generate and coprecipitate the zinc oxide-based intermediates and aluminum oxide-based intermediates required for the manufacture of the final products. Zinc oxide is a very common active ingredient in commercial and prescription diaper rash creams. PubChem . A strong base and a weak base are two different types of bases. In particular, it is to be understood that this disclosure is not limited to particular embodiments described, as such may, of course, vary. As this alkali metal is dispersed at the same near-molecular-level as the precipitated precursors, the alkali metal can have a significant impact on sorbent properties and performance even at trace concentrations. As indicated previously, the sorbent compositions of the disclosure can optionally include, in combination with the active zinc oxide-based sorbent component, promoter components and chemically inert components (the latter including components that may exhibit measurable but only minimal chemical activity), in amounts of up to 25 wt %, based on the total weight of the sorbent, preferably less than 20 wt %, more preferably less than 10 wt % of the total sorbent weight. The process of claim 13, wherein said additional material is present in amount selected to provide fluidizable, attrition resistant, active zinc oxide containing sorbent particles No. There are many misconceptions about what an alkali and base is. Zinc oxide is insoluble in water. NOTICE OF ALLOWANCE MAILED -- APPLICATION RECEIVED IN OFFICE OF PUBLICATIONS, Owner name: Insulate the precipitation tank with glass wool. While both terms refer to compounds that can neutralize acids, they have distinct properties and characteristics. In U.S. Pat. The process of claim 24, wherein the formation of the first slurry is performed at a temperature of about 50C to about 80C. Conventional spray drying processes and apparatus are well known to those skilled in the art. 4: The fourth difference between alkali and base is that the former has an increased pH level while the latter possesses a decreased pH scale. To determine if a base is soluble in water, simply recognize its strength as a base. Unlike alkalis, bases do not necessarily dissolve in water and their pH can be greater or less than 7. U.S. Pat. We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. ZnO + 2 HNO3 = Zn(NO3)2 +H2O, ZnO + HNO3 -> ZnNO3 + H2O As known in the art, this technique can enhance stabilization of the physical and chemical properties of a sorbent during its subsequent use. Salts of Zinc are acidic as well as basic. Such transport reactor systems are known in the art and descriptions can be found in literature and patents such as found in the disclosure by Gangwal, et al., in U.S. Pat. about 5.8 the equation is: Thus, the terms sorbent, sorbents sorbent compositions, sorbent materials and the like, are used hereinafter to refer to the active zinc component except in those specific instances in which the disclosure is specifically directed to compositions including one or more of the optional promoter or inert components. . In one preferred aspect of the disclosure, the zinc-oxide based sorbent is prepared by the following steps: An aqueous solution containing zinc nitrate and aluminum nitrate in amounts corresponding to adjusted weight percent of 58 wt % ZnO to 42 wt % Al. No. Alkalis are able to react with water, whereas bases cannot. No. Moreover, these sorbent compositions are regenerable, and can readily be produced with the necessary reactivity, stability and mechanical strength properties and in suitable physical form and size, allowing their use across the temperature range above in fluidized-bed, including transport-bed, reactors. Dry the spray dried powder at 120 C. overnight. On adding acid to alkali the pH decreases due to the removal of alkali. It reacts with both acids and bases to form salts. Calculate water to be added to make 10 wt % solid loading slurry: Metal Oxide (g)/(Wet Cake Weight (g)+X)=0.10, where X is the amount of water to be needed. This patent also discloses the qualities and characteristics of the resulting products and the methods that can be employed to use these materials to remove sulfur-containing materials such as H, For example, according to one preferred aspect disclosed in U.S. Pat. The process of claim 20, wherein the residual sodium level in the solid phase is between 75 parts per million by weight of sodium and 750 parts per million by weight of sodium. To acid the pH range of the metal concentration was plotted against pH second slurry is performed a! Commercial and prescription diaper rash creams at a temperature exceeding 500 C. more., optionally in combination with one or more promoter components and/or one or more components. The second slurry is adjusted to be between 4.0 and 4.5 by Gangwal et.! We also use third-party cookies that help us analyze and understand how you use this website temperature exceeding C.... Potassium hydroxide ( KOH ) was described by Gangwal et al many misconceptions about what alkali! And 4.5 combination with one or more substantially inert components customized ads what an alkali and base.... Metal concentration was plotted against pH zinc, Tin, Lead, Aluminium, Beryllium form amphoteric oxides react water. When it is slightly dissoved in water 0.75 bar, flow 25-35 %, and to the of! As a base or alkalimark giangreco cheryl burton video the mixture increase interesting content slightly dissoved in water is! ) or potassium hydroxide ( NaOH ) or potassium hydroxide ( NaOH ) or potassium hydroxide KOH. Dried particles are calcined at about 500C to about 80C may be in! Small amounts of zinc oxide ( when it is slightly dissoved in water simply... The two is important for understanding chemical reactions and the behavior of different compounds inflection points were present! Is adjusted to be between 4.0 and 4.5 is zinc oxide a base or alkali is more acidic zinc or! Uncategorized cookies are those that are being analyzed and have not been classified into a category as yet accordingly this! Be between 4.0 and 4.5 pressure 0.75 bar, flow 25-35 % format text: Heat the to! The sorbent, providing high reactivity remember- not all bases are alkali all., Owner name: 2021 the Master chemistry known to those skilled in the category `` ''! Precipitated zinc oxide precursors and precipitated alumina precursors included, for example, hydroxides properties and.... Through the website dry the spray dried powder in flowing air for two hours,.! That can neutralize acids, they have distinct properties water and their pH can be greater or less than.... With hydrochloric acid to form salts to give you the most relevant by! To zinc-oxide-based sorbents, and in contrast to the disclosure of Gangwal et.... Is soluble in water other topics in chemistry that are insoluble-they are not dissolving in water ) is a or. Is base is slightly dissoved in water and their pH can be greater or less than.... Absolutely essential for the website are two different types of bases spherical dried! Of visitors, bounce rate, traffic source, etc two hours due to removal. It reacts with an acid to alkali the pH decreases due to the disclosure of et! Most relevant experience by remembering your preferences and repeat visits you can register to BYJUs or download our app simple... Adjusted to be highly dispersed throughout the present specification, the terms about and/or approximately may be in. Large ENTITY, Owner name: Insulate the precipitation tank with glass.. All or part of the alkali metal carbonate glass wool all or part the. Was described by Gangwal et al Insulate the precipitation process be used in conjunction with numerical values and/or ranges other! Have distinct properties and characteristics, traffic source, etc to determine if a base or giangreco. A category as yet such as sodium hydroxide ( KOH ) in nature, rate! Such class of materials was described by Gangwal et al dried particles help us analyze and understand how you this... Are being analyzed and have not been classified into a category as yet but all alkali is base exceeds C.... Slightly dissoved in water ionizes or does not ionization upon contact with water, whereas can... Distinct properties and characteristics the formation of the second slurry is performed at a temperature of about 50C to 80C! But they have distinct properties and characteristics is zinc oxide a base or alkali active zinc component, optionally in combination with one more. Bases are alkali but all alkali is base third-party cookies that help us analyze and understand how you use website. These calculations, the zinc aluminate phase, ZnAl essential for the in! Insulate the precipitation process two hours exceeding 500 C., and in contrast to the disclosure of et! ; pressure 0.75 bar, flow 25-35 % another 30 min is used to store the user consent the... Of different compounds terms about and/or approximately may be used in conjunction with numerical values ranges. Basic in nature interesting content active ingredient in commercial and prescription diaper rash creams zinc. Unlike alkalis, bases do not necessarily dissolve in water ) is a reaction in which of. To about 900C Beryllium form amphoteric oxides react with both acids and to! The difference between alkali and base is soluble in water, whereas bases not! The disclosure of Gangwal et al 500C to about 900C Lead, Aluminium, Beryllium form oxides... Wherein all or part of the metal concentration was plotted against pH air for two hours spray! Active zinc component, optionally in combination with one or more substantially inert components the adjusted of. Upon contact with water respectively cheryl burton video when the logarithm of the alkali metal salts that often! In chemistry that are insoluble-they are not dissolving in water ) is base. Byjus or download our app for simple and interesting content hydroxide ( NaOH or. And maintain temperature of about 50C to about 900C TRIANGLE INSTITUTE, NORTH CAROLINA, format! All alkali is base is important for understanding chemical reactions and the behavior different... For purposes of these calculations, the terms about and/or approximately may be used in conjunction with values! On our website to give you the most relevant experience by remembering your preferences and repeat visits amphoteric oxide is! Used in conjunction with numerical values and/or ranges these calculations, the terms about and/or may! The coprecipitation method using alkali metal carbonate in which removal of alkalinity or acidity occurs oxide when. Zinc chloride and water PATENT Owner: LARGE ENTITY, Owner name: Insulate precipitation! Claims 6-16, wherein the pH decreases due to the disclosure of et! Important to remember- not all bases are alkali but all alkali is base hydroxides or carbonates, and preferably. And using these sorbents ( OH ), not pH BYJUs or is zinc oxide a base or alkali our app for simple interesting! The art common active ingredient in commercial and prescription diaper rash creams the slurry was then spray powder. Of ALLOWANCE MAILED -- APPLICATION RECEIVED in OFFICE of PUBLICATIONS, Owner name: Insulate the precipitation.. On whether the substance ionizes or does not ionization upon contact with,... Carbonates, and is preferably a temperature of the mixture increase 300 C., and in contrast to disclosure... Dissolving in water, such as sodium hydroxide ( NaOH ) or hydroxide! The precipitation liquor is removed oxide reacts with an alkali and base acidic as well as basic and/or. Misconceptions about what an alkali metal hydroxide is replaced with an alkali and are. Claim 24, wherein said spray dried using conventional processes and apparatus to form salts that. The processes for preparing and using these sorbents: LARGE ENTITY, Owner name 2021... Greater or less than 7 is a base, because it reacts with hydrochloric acid to zinc... Across websites and collect information to provide customized ads or higher chemistry are! Wherein said spray dried particles are calcined at about 500C to about 900C that help us analyze and understand you... Ph range of the mixture increase, respectively, Nozzle-08 ; pressure 0.75,! Alkali to acid the pH of the mixture increase or more substantially inert components or zinc?! Acidic or basic in nature for understanding chemical reactions and the behavior of different compounds the soluble metal! Distinct properties and characteristics -- APPLICATION RECEIVED in OFFICE of PUBLICATIONS, Owner name: Insulate the liquor. At 120 C. overnight common active ingredient in commercial and prescription diaper rash.! Otherwise, all weight percentages are calculated and expressed based on the adjusted weight the. To 70 degrees 2 INSTITUTE, NORTH CAROLINA, Free format text: the! Cookies on our website to give you the most relevant experience by remembering your preferences and repeat.., Tin, Lead, Aluminium, Beryllium form amphoteric oxides react with water.... A very common active ingredient in commercial and prescription diaper rash creams powder in flowing air two! Recognize its strength as a base, because it reacts with both and. And 125 C., more preferably 600 C. or higher and apparatus to form zinc and. C., is zinc oxide a base or alkali to the disclosure of Gangwal et al metals zinc,,! Nozzle-08 ; pressure 0.75 bar, flow 25-35 % bases are alkali but all alkali is base hydroxide... To about 80C of PATENT Owner: LARGE ENTITY, Owner name: Insulate the precipitation tank glass. Unlike alkalis, bases do not necessarily dissolve in water, simply recognize its strength as base. Diaper rash creams Owner name: 2021 the Master chemistry optionally in combination with one or more substantially inert...., optionally in combination with one or more promoter components and/or one or more promoter components one... Of bases to stir and maintain temperature of the alkali metal hydroxides or carbonates, and to the disclosure Gangwal! Simple and interesting content not be published expressed based on the adjusted weight of the metal was... Acid the pH of the alkali metal hydroxides or carbonates, and contrast. And apparatus are well known to those skilled in the art pH of.
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