PERP Program New Report Alert

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1 PERP Program New Report Alert May 2005 Nexant s ChemSystems Process Evaluation/Research Planning program has published a new report, Hydrogen Peroxide (03/04-5). Technology Overview Although at one time most hydrogen peroxide was produced by electrolysis of ammonium bisulfate, virtually all production is now based on a process featuring catalytic hydrogenation followed by auto-oxidation of a suitable organic carrier molecule, predominantly an alkylated anthraquinone. Solvay has announced the development of its so-called high-yield process, based on an optimized distribution of anthraquinone and related species. The process will be implemented at Finnish Peroxides, a joint venture between Solvay and UPM-Kymmene of Finland. A novel electrochemical process for the production of alkaline hydrogen peroxide has been developed by Dow. The process employs a monopolar cell to achieve an electrolytic reduction of oxygen in a dilute sodium hydroxide solution. The 4 percent alkaline solution of hydrogen peroxide is too dilute to ship, but is well suited for onsite pulp bleaching. A Shell Chemical process based on the oxidation of isopropyl alcohol, practiced commercially from 1957 to 1980, and a Lyondell (ARCO) Chemical process developed in the early 1970s but not commercialized are discussed in the report. There have been many patents issued in recent years covering the direct catalytic reduction of oxygen by hydrogen. DuPont piloted this technology and claimed at one point to have a process ready for commercial scale application. The status of this technology is uncertain in view of DuPont s exit from the hydrogen peroxide business. Mitsubishi Gas Chemical (MGC) in Japan and Interox in Europe have also been prominent in this area. Princeton Advanced Technology is developing a direct combination process based on an acidic aqueous reaction medium without halides. Degussa and Headwaters Inc. announced September 28, 2004 that they are planning a 50:50 joint venture to develop and commercialize a direct synthesis process for hydrogen peroxide by Business Situation Incentive for technology development and commercialization has been diminished by industry overcapacity and resulting weakness in product pricing. In response to overly optimistic growth expectations, worldwide hydrogen peroxide capacity was expanded significantly in the period. Demand has not kept up with this expanded capacity, leading to oversupply and weak pricing. In the United States, capacity increased about 50 percent in the period, whereas

2 - 2 - in the latter part of this period U.S. H 2 O 2 demand growth slowed dramatically due to weakness in the paper industry, which accounts for about 59 percent of North American hydrogen peroxide demand. Choices for pulp bleaching that meet U.S. regulations by avoiding elemental chlorine include elemental chlorine free (ECF) and totally chlorine free (TCF) technologies. ECF technology typically uses sodium chlorate or chlorine dioxide as bleaching agent. TCF technology utilizes hydrogen peroxide, oxygen, or ozone (or a combination of these) as bleaching agent and can use up to 44 pounds of H 2 O 2 per ton of pulp. However, the conversion from ECF to TCF has been slowed by cost considerations. Environmental applications such as wastewater treating are expected to grow at rates in excess of GDP growth. High purity hydrogen peroxide is finding good growth as a replacement for halocarbon solvents in cleaning of semiconductors and printed circuit boards. Growth of hydrogen peroxide use in manufacture of other chemicals is modest to date, but several consortia are planning large-scale hydrogen peroxide plants to feed a propylene oxide route that is nearing commercialization. BASF and Dow announced in August 2002 their intentions to jointly develop and commercialize a hydrogen peroxide-based propylene oxide (PO) process. BASF and Dow are planning to build a 300,000 metric tons per year plant by 2007 based on hydrogen peroxide technology. The BASF link-up with Dow is said to not affect its 50:50 joint venture formed with Solvay in May The venture is to build a 250,000 metric ton per year hydrogen peroxide-based PO plant for start-up in 2007 at an undisclosed location. Degussa announced in April 2001 that it is developing a hydrogen peroxide-based propylene oxide process in association with Krupp-Uhde. The Degussa-Uhde process was to have been commercialized in a 60,000 metric ton per year plant for Sasol in South Africa, but it was announced in April 2004 that the project was being shelved. Several producers have closed older facilities after starting new capacity at the same sites. DuPont has withdrawn from the market and sold its plants to competitors. Anthraquinone Autoxidation The first commercial anthraquinone (AQ) process was operated by I.G. Farbenindustrie in Germany during World War II. In this process, also known as the Riedl-Pfleiderer process, a 2- alkylanthraquinone, for example 2-ethylanthraquinone, dissolved in a suitable solvent or solvent mixture, is reduced catalytically to the corresponding anthroquinol or anthrahydroquinone (AHQ). The anthraquinone is commonly called the working compound, whereas the anthraquinone/solvent mixture is called the working solution. The AHQ undergoes further hydrogenation to yield the 5,6,7,8-tetrahydroanthrahydroquinone (THAHQ). Both the AHQ and the THAHQ are active compounds. They are oxidized in a separate step that regenerates the corresponding quinone

3 - 3 - compounds, AQ and tetrahydroanthraquinone (THAQ), and simultaneously produces hydrogen peroxide. One of the limiting factors in productivity is the amount of quinone that can be retained in solution through the cyclic oxidation/reduction process. Two means of solving this problem are changing the substituent group on the anthraquinone to increase its solubility, and changing the solvent or solvent mixture. The hydrogenation step in the cyclic process to produce hydrogen peroxide involves hydrogenating the working solution in the presence of a catalyst such as supported palladium or Raney nickel at temperatures of C under a hydrogen partial pressure up to 4 atmospheres. Hydrogen is usually completely consumed in a reaction time of 1 to 5 minutes. The working solution is cooled to remove the heat of hydrogenation, which it carries as sensible heat. The hydroquinone is oxidized by an oxygen-containing gas, usually air, to produce hydrogen peroxide and regenerate the quinone. Economics and safety considerations favor air over pure oxygen. The oxidation is carried out noncatalytically by bubbling air through the solution at C at near atmospheric pressure. The oxidation step is typically designed to utilize percent of the oxygen in the incoming air. Oxygen partial pressure and working solution residence time are the principal variables that influence the operation. Residence time usually ranges from 10 to 40 minutes. Various methods have been proposed for separating crude hydrogen peroxide from the working solution, but the method most generally used involves extraction with water. Hydrogen peroxide concentration in the working fluid is 0.8 to 1.9 weight percent. Efficient extractors recover more than 95 percent of the hydrogen peroxide. This crude product, at concentrations of 25 to 45 percent hydrogen peroxide, must be upgraded to meet commercial requirements for purity and concentration. The peroxide-synthesizing capacity of the working solution decreases with continued cyclic operation because of degradation of the anthraquinone working intermediate. The loss of anthraquinone is compensated for by the introduction of fresh quinone compound into the working solution. However, the resulting gradual increase in the overall concentration of solids interferes with the reaction and increases the density and viscosity of the solution, leading to fouling of the hydrogenation catalyst and process equipment. Countermeasures include retarding the formation of decomposition products or limiting the buildup of by-products via removal and/or regeneration as they are formed. The effective capacity of plants using the AQ process is typically 85 to 90 percent of nameplate capacity; that is, the on stream factor is only percent of nameplate, primarily as a consequence of the decline in the efficiency of the working solution over time. Process yields are high. Hydrogen consumption corresponds to better than 95 mole percent yield to hydrogen peroxide. Working compound makeup is about pounds per pound of product (for 2- ethylanthraquinone).

4 - 4 - Developing Direct Synthesis Processes A process for the direct reaction of hydrogen and oxygen represents a considerable challenge in catalysis and process design. The reaction is accomplished with oxygen rather than air and platinum group catalysts in an acidic aqueous solution, usually containing halide. Halide ions give improved hydrogen selectivity and peroxide concentration, but decrease the activity of the platinum group metal. This is an extremely corrosive medium, although it is typically mitigated by the low reaction temperatures (0 C-25 C) employed. Still, there are limited, expensive material choices for the reactor. Elution of the platinum catalyst component is proportional to the halide ion concentration and results in decreased catalytic activity/lifetime and deterioration of hydrogen peroxide quality. The platinum concentration in the product is too low to easily recover. However, for most uses, the peroxide product must be post-treated to remove halide ions. In order to be out of the explosive region, mixtures of hydrogen and oxygen must contain less than about 4 percent hydrogen. A typical reaction scheme involves feeding oxygen and hydrogen individually to the liquid phase reaction and maintaining the concentration of hydrogen in the recycle gas loop below 4 percent. Oxygen represents a significant cost item in such systems. The concentration of hydrogen peroxide produced is generally low at practical selectivities. The production of relatively dilute peroxide incurs a penalty for concentration, both in capital and utilities. The presence of potentially volatile halide could necessitate exotic materials for columns as well as the reactor. A novel reactor configuration has been patented by Princeton Advanced Technology and later by Advanced Peroxide Technology. The reactor design centers on dispersing tiny bubbles of oxygen and hydrogen in a controlled manner while surrounded by enough liquid to suppress any runaway reaction within the bubbles themselves. The liquid medium comprises an acidic aqueous solution and a Group VIII metal catalyst. Hydrogen is sparged into the flowing medium where it dissolves. Oxygen bubbles are reacted with the dissolved hydrogen to produce hydrogen peroxide. The liquid medium is circulated at a high rate, preferably a velocity of at least ten feet per second for providing a bubbly flow regime in the reactor. The reactor takes the form of a series of heavy wall thickness pipes connected together. Typical operating conditions are 2,000-5,000 psi and 0-60 C. This scheme uses no organic chemicals, leading to safety and product purity advantages, and is capable of producing 3-15 percent aqueous peroxide product without further concentration. Degussa and Headwaters Inc. announced September 28, 2004 that they are planning a 50:50 joint venture to develop and commercialize a direct synthesis process for hydrogen peroxide by The process gives hydrogen peroxide dissolved in low concentrations of methanol, particularly well suited for direct use in production of chemical intermediates such as propylene oxide and possibly caprolactam, phenol, and epichlorohydrin. Other companies activities in direct H 2 O 2 synthesis are also discussed in the report.

5 - 5 - Economics A comparison of the economics of the established generic anthraquinone based process, and the developing Princeton Advanced Technology direct synthesis process is presented in detail in the report. While the Princeton process has somewhat higher raw material and utility costs than the anthraquinone process, the remaining cost elements are related to investment and labor requirements, which in turn are a function of process complexity. Fewer equipment pieces and smaller sizes benefit the Princeton process relative to the anthraquinone process. Reflecting these fixed cost elements, the cost plus investment return for the Princeton process is about 20 percent less than the anthraquinone process. Investment for the Princeton process will likely increase with further development, narrowing the indicated advantage, due to the usual tendency for additional equipment to be found necessary as process development progresses towards commercialization. Sensitivity to changes in investment requirements and plant capacity are presented in the report for both the anthraquinone and direct-synthesis processes. Commercial Applications/Grades Hydrogen peroxide is a strong, nonpolluting oxidizing agent, and most of its uses and those of its derivatives depend on this property. The applications for hydrogen peroxide fall into the following broad categories: Pulp/paper bleaching Water/waste and effluent treatment Chemical synthesis (PO) Textile bleaching Mining/metallurgy Electronics (semiconductors) Propulsion Desulfurization Food Miscellaneous Hydrogen peroxide is available in three common product strengths (e.g. as 35, 50, and 70 weight percent aqueous solutions). While transportation costs per pound of contained hydrogen peroxide decrease with increasing concentration, handling hazards, such as severity of tissue burns and ease of ignition of combustibles, increase with increasing concentration.

6 - 6 - Various product grades exist, tailored to the needs of specific end use industries. Technical grade hydrogen peroxide is suitable for use in the pulp and paper, textile, waste treatment, and metal extraction and finishing industries. Technical grade hydrogen peroxide is stabilized with low levels of tin based stabilizers and phosphates. Still lower amounts of these stabilizers are used in food grade hydrogen peroxide products, which must meet stringent residue requirements (e.g. 6 ppm tin). Organic based stabilizers are used in hydrogen peroxide grades destined for use in organic synthesis reactions due to possible interference of inorganic stabilizers with the intended reactions, and in some types of metal treatment, where inorganic stabilizers may cause staining of treated substrates. High value-added electronic grade products are left unstabilized, since stabilizers would interfere with the intended end uses. Electronic grades are shipped in teflon lined containers and require stringent handling procedures to maintain product purity and safe operations. Propulsion grades (70-98 percent assay) meet the most stringent specifications for monopropellant, bipropellant, and hybrid propulsion applications and are shipped in high-purity aluminum drums and tank trucks. Electronic/semiconductor grades are available with total cationic impurity levels of < 10 parts per billion (ppb), <1 ppb, < 0.1 ppb, and <0.01 ppb to meet the needs of various electronic applications. Separate, lower impurity specifications apply to individual cations depending on the degree of difficulty they cause in chip fabrication, etc. Food grade hydrogen peroxide is used for pre-fill sterilization of asceptic packaging (e.g. juice drinks, dairy products, tomato products, etc.), as well as food bleaching, spoilage control, and sulfur removal. Cosmetic grade hydrogen peroxide is used in pharmaceutical as well as cosmetic applications for germ fighting antiseptics that are non-staining, contact lens cleaning solutions, etc. This grade is specially stabilized to avoid breakdown when diluted to low concentrations (3-9 percent). Pulp/Paper Bleaching Hydrogen peroxide is considered an environmentally safe oxidizing agent in the pulp bleaching process, which does not generate chlorine derivatives in the pulp suspension and therefore is displacing chlorine, chlorine dioxide, and other reagents in a number of pulp bleaching operations. Incremental bleaching using hydrogen peroxide alone can be added as an intermediate or final step in Kraft pulp bleaching. It is also commonly used in bleaching acidic sulfite pulps, which are easier to bleach than Kraft pulps. Hydrogen peroxide is essential in producing higher brightness mechanical pulps and has largely superseded the use of sodium hydrosulfite in many regions. The use of hydrogen peroxide, in combination with caustic soda, is a well established method for bleaching mechanical pulps and deinking of recycled waste paper. Bleaching with hydrogen peroxide achieves high, stable brightness and helps to improve strength as well as optical properties, while maintaining high process yield.

7 - 7 - Waste Treatment In municipal waste water treatment, H 2 O 2 is used primarily to cope with extraordinary situations such as control of hydrogen sulfide (H 2 S) produced during transportation of waste water in sewer pipes. Another application is to control filamentous bulking in biological treatment plants. The most significant environmental markets for hydrogen peroxide are in the treatment of a wide variety of industrial wastes and waste waters. Hydrogen peroxide provides a versatile treatment chemical that can solve many waste treatment problems, such as the removal of cyanide, thiocyanate, and nitrite; chlorine or hypochlorite; or organic compounds. Hydrogen peroxide is also used as a source of hydroxyl radicals in more complex Advanced Oxidation Processes. Hydroxyl radicals are the second most powerful oxidant available, behind only fluorine. In situ biorestoration of contaminated soil with hydrogen peroxide offers the advantage that soil can be treated in place, saving removal/replacement costs and minimizing worker exposure. Chemical Synthesis Hydrogen peroxide has numerous applications in the chemical process industry. High purity ferric sulfate, hydrazine, perborates and percarbonates are typical targets of inorganic synthesis with hydrogen peroxide. Applications in organic synthesis include epoxidation (preparation of propylene oxide) and hydroxylation (manufacture of plasticizers and stabilizers in the polymer industry), oxohalogenation (flame retardants), and initiation of emulsion polymerization (MEK peroxide, benzoyl peroxide, lauryl peroxide). Textile Bleaching Hydrogen peroxide is the major bleaching agent used for textiles. It has advantages over alternatives (e.g. sodium hypochlorite and sodium hydrosulfite) in that it is suitable to continuous processing, has no severe toxicity and effluent problems, and is noncorrosive. Metals Processing Hydrogen peroxide is used in a number of applications in mining and in the processing of metal, including: extraction and purification of uranium, gold extraction, extraction and separation of chromium, copper, cobalt, tungsten, molybdenum, and other metals, and metal treatments (e.g. etching, stainless steel pickling, nonferrous metal finishing).

8 - 8 - Electronics There are two uses of high purity hydrogen peroxide specific to the electronics industry, namely germanium and silicon semiconductor wafer cleaning and printed circuit board (PCB) etching. Hydrogen peroxide is also widely used throughout the industry as a metal cleaner or etchant. A further related use is the regeneration of cupric chloride etching baths. Miscellaneous Treating Chemical purification provides diverse applications for hydrogen peroxide in the removal of color, odor, minor chemical contaminants, or any combination of these. Hydrogen peroxide can be applied at mild conditions over a broad ph range and in the presence of solvents, catalysts, and other purification agents. Sulfur dioxide can be removed from offgases occurring in metal smelting, chemical and pharmaceutical synthesis, production of graphite, titanium dioxide, and sulfuric acid, as well as combustion of sulfur-containing fuels. Mercaptans and hydrogen sulfide can also be treated with hydrogen peroxide, as can nitrogen oxides. Supply and Demand Historical and projected ( ) hydrogen peroxide supply and demand are provided in the report for the United States, Western Europe, and Japan. = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Copyright by Nexant, Inc All Rights Reserved. Nexant, Inc. ( is a leading management consultancy to the global energy, chemical, and related industries. For over 38 years, Nexant/ChemSystems has helped clients increase business value through assistance in all aspects of business strategy, including business intelligence, project feasibility and implementation, operational improvement, portfolio planning, and growth through M&A activities. Nexant s chemicals and petroleum group has its main offices in White Plains (New York) and London (UK), and satellite offices worldwide. These reports are for the exclusive use of the purchasing company or its subsidiaries, from Nexant, Inc., 44 South Broadway, 5 th Floor, White Plains, New York U.S.A. For further information about these reports contact Dr. Jeffrey S. Plotkin, Vice President and Global Director, PERP Program, phone: ; fax: ; jplotkin@nexant.com; or Heidi Junker Coleman, phone: , address: hcoleman@nexant.com, Website: