LINEAR ALKYLATE SULFONATES

Transcription

1 February A Surface-Active Page 1 CEH Marketing Research Report LINEAR ALKYLATE SULFONATES By Robert F. Modler with Rene Willhalm and Yuka Yoshida CEH Marketing Research Reports provide comprehensive analysis, historical data and forecasts pertaining to the international competitive market environment for chemical products. Detailed supply and demand data are developed for the United States, Western Europe and Japan with the cooperation of chemical producers and consumers worldwide. Updated information may be available from the following CEH Program services: CEH Online The full text retrieval and update database. Updated monthly. CEH CD-ROM The entire contents of the CEH on one CD-ROM and including CEH Online updates. Issued quarterly. Manual of Current Indicators (MCI) Updates of statistical data derived from published sources. Issued quarterly. The Economic Environment of the Chemical Industry (EECI) Economic indicators that impact the chemical industry; issued quarterly with the MCI. CEH Inquiry Service SRI Consulting researchers are available to answer your questions. U.S.A. Telephone: 650/ Fax: 650/ Zurich Telephone: 411/ Fax: 411/ Tokyo Telephone: 813/ Fax: 813/

2 B Page 2 TABLE OF CONTENTS Summary... 2 Manufacturing Processes... 5 Environmental Issues... 7 Supply and Demand by Region... 7 United States... 7 Producing Companies... 7 Salient Statistics Consumption Household Products Heavy-duty laundry detergents (powders and liquids) Historical LAS consumption patterns Light-duty liquid detergents Miscellaneous household cleaners Industrial, Institutional and Commercial Applications Price Trade Canada Mexico Western Europe Producing Companies Salient Statistics Consumption Household Products Heavy-duty laundry powders Heavy-duty laundry liquids Light-duty dishwashing liquids Other household cleaners Industrial, Institutional and Commercial Applications Price Trade Eastern Europe Producing Companies Consumption Japan Producing Companies Salient Statistics Consumption Price Trade Bibliography... 41

3 C Page 3 SUMMARY Linear alkylbenzene sulfonate (LAS) is the world s largest-volume synthetic surfactant and is widely used in household detergents as well as in numerous industrial applications. It was developed as a biodegradable replacement for nonlinear (i.e., branched) alkylbenzene sulfonate (BAS) and has largely replaced BAS in household detergents throughout the developed countries. The products referred to as LAS or linear alkylate sulfonates include the various salts of sulfonated alkylbenzenes as well as the free acid. LAS is generally produced in equipment that is also used to produce other sulfonated/sulfated products; therefore, capacities far exceed demand for LAS alone. The following table shows the 1994 supply/demand balance for LAS in the three major world areas: Supply/Demand for LAS by Major Region 1994 (millions of pounds) United States a Western Europe Japan Total Capacity b 2,288 >2, >5,518 Production ,911 Imports 5 neg 9 14 Exports Consumption ,852 (thousands of metric tons) United States a Western Europe Japan Total Capacity b 1,038 >1, >2,503 Production Imports 2 neg 4 6 Exports Consumption a. Production and consumption in Canada amounted to about 73 million pounds (33 thousand metric tons), and production and consumption in Mexico amounted to about 452 million pounds (205 thousand metric tons). b. Capacity data for the United States and Western Europe refer to total sulfonation capacity and include capacity to produce other sulfonated or sulfated products; Japanese capacity data are for dedicated LAS production. CEH estimates. About 85% of LAS is used in household detergents, including laundry powders, laundry liquids, dishwashing liquids and other household cleaners. Industrial, institutional and commercial detergents account for most of the other applications of LAS, but it is also used as an emulsifier (e.g., for agricultural herbicides and in emulsion polymerization) and wetting agent. The following table shows a breakdown in the use of LAS in the various end-use categories, as well as projections for future market changes over the period.

4 D Page 4 Consumption of LAS by Major Region 1994 (millions of pounds) United States Western Europe Japan Total Laundry Powders Laundry Liquids Dishwashing Liquids Other Household Cleaners Nonhousehold Uses Total ,852 6 (thousands of metric tons) United States Western Europe Japan Total Laundry Powders Laundry Liquids Dishwashing Liquids Other Household Cleaners Nonhousehold Uses Total Average Annual Growth Rate (percent) % 2% 1.5% CEH estimates. LAS competes with several other major surfactants for use in household detergents. Some of the competitive surfactants have greater hard-water tolerance and better compatibility with enzymes, and are milder than LAS. Because of its low cost and other favorable properties, however, LAS will remain a major surfactant for many years. Although the consumption of LAS in the United States, Western Europe and Japan will probably remain unchanged or decline slightly, its consumption in the developing world is likely to grow rapidly. Most of the LAS production is accounted for by detergent manufacturers that captively consume it. The largest of these detergent manufacturers are the Procter & Gamble, Unilever, Colgate-Palmolive, Henkel, Lion and Kao groups. The latter two operate principally in Japan and other East Asian countries. The balance of LAS production is accounted for by chemical producers that also sell to detergent manufacturers, either directly or through toll sulfonation arrangements. The large chemical producers of LAS also supply it to smaller detergent manufacturers that have no LAS production capability and to industrial and institutional cleaning companies. The merchant suppliers may also sell LAS in the form of formulated products. Examples of large merchant suppliers are Stepan Company in the United States, the Huels Group in Western Europe and Tayca Corporation in Japan.

5 E Page 5 MANUFACTURING PROCESSES Linear alkylbenzene sulfonic acid is prepared commercially by sulfonating linear alkylbenzene (LAB) with either oleum (10-25% sulfur trioxide [SO 3 ] in sulfuric acid) or an SO 3 -air mixture. In both processes, sulfur trioxide is the sulfonating agent and the major product is p-alkylbenzene sulfonic acid. Both batch and continuous processes are used. One advantage of the SO 3 -air route is that it is easier to produce lighter-colored sulfonic acid using this process than with oleum. In addition, the oleum route leads to a product that contains a significant level of by-product sodium sulfate. Although the oleum-derived product is readily formulated into powders, it is less desirable for use in formulating liquid products, where the excess sodium sulfate can create solubility problems. Thus, the SO 3 -air process is the preferred route for LAS used in liquid formulations. Since merchant producers of LAS prefer a product that can be sold for either use, all have converted to the SO 3 -air process. Also, merchant producers are able to use the same process and equipment to produce other sulfonates (e.g., alpha-olefin sulfonates and methyl ester sulfonates) and sulfates (e.g., alcohol sulfates and alcohol ether sulfates). Some detergent manufacturers that captively consume most of their product in powders and liquids continue to use both routes, but they rely on the older oleum route for most of their powder formulations and use the newer SO 3 -air route for most of the LAS used in liquid formulations. As of late 1995, only five oleum plants were operated by detergent manufacturers still producing LAS in the United States. In a typical batch oleum sulfonation process, oleum is added to the LAB reaction mixture at the suction side of a pump that is recycling the contents of the reactor. Under normal commercial conditions, pounds of oleum are required per pound of linear alkylbenzene. The reaction temperature is carefully controlled while the acid is added, and the reaction goes to completion during a 30- to 45-minute digestion period. Excessive time or high temperature produces undesirable dark-colored products. In a typical continuous oleum sulfonation process, oleum and LAB are proportioned to a reactor mixing head and the reaction temperature is closely controlled using recycling of the reaction mixture through a heat exchanger. The reaction is generally completed in eight to fifteen minutes. Whether batch or continuous, the reaction is carried out until sulfonation is 98-99% complete. Sulfonation with oleum produces linear alkylbenzene sulfonic acid containing considerable excess sulfuric acid. If this material is neutralized with aqueous sodium hydroxide, the resulting low-active detergent slurry contains about four parts of sodium sulfate for every six parts of the active LAS. These low-active detergent slurries are somewhat restricted in their areas of application because of the high sodium sulfate content. This shortcoming of the oleum-derived products may be partially overcome by adding enough water to the final sulfonation reaction mixture to dilute the sulfuric acid present from about 98% to 71-72%. At this concentration, the sulfuric acid is insoluble in the linear alkylbenzene sulfonic acid and separates as a second layer. Decanting of this sulfuric acid layer leaves an upper phase containing 87-90% linear alkylate sulfonic acid and only 7-9% sulfuric acid. When this product is neutralized with caustic soda, a high-active detergent slurry results. In a typical batch SO 3 -air process, liquid sulfur trioxide is vaporized in a stream of dry air, and the resulting 5-15% SO 3 stream is then reacted with the linear alkylbenzene.* As in oleum processes, good mixing and heat removal are necessary to avoid oxidation and charring, which result in dark-colored products. The reaction mixture is digested to complete the reaction. Air and the small remaining excess * One variation of the batch process uses a liquid sulfur trioxide sulfur dioxide mixture in which the sulfur dioxide acts as a diluent for the sulfur trioxide, as a solvent for the reaction and as a refrigerant so that the reaction can be run at very low temperatures ( 7 to 9 C).

6 F Page 6 of sulfur trioxide (only a 3-5% molar excess is used) are removed. The reaction mixture is then hydrated with a small amount of water to hydrolyze any alkylbenzene sulfonic acid anhydrides present in the reaction mixture. In continuous SO 3 -air processes, the color of the sulfonic acid products is improved by careful control and maintenance of reaction temperatures. Variations in the method of temperature control include recycling the reaction mixture through heat exchangers and the use of two or more reactors connected in series. When the mixture is neutralized with sodium hydroxide, a 96-97% sulfonate product is obtained. The free acid in a liquid form (97% active) is the product most commonly sold in the merchant market, since it can be transported at the lowest cost. Shipping a 40% solution of the sodium salt is more expensive since it adds the cost of transporting large volumes of water. Most of the free acid is ultimately converted to the sodium salt by detergent manufacturers and other end users. The sodium salt is preferred, because it combines low cost with physical and performance properties suitable for a wide range of applications. For certain applications, however, other inorganic salts (e.g., ammonium, calcium, potassium) and organic amine salts (e.g., isopropylamine, triethanolamine) are also prepared. It is estimated that an average of pound of LAB is required per pound of sodium alkylbenzene sulfonate produced. Production of linear alkylbenzene sulfonic acid and neutralization to the corresponding sodium salt may be illustrated as follows: R R + H 2 SO 4 /SO 3 oleum or SO 3 /air + H 2 SO 4 mol wt: linear alkylbenzene 246 (average C 12 chain) SO 3 H linear alkylbenzenesulfonic acid 326 (average C 12 chain) R R + NaOH + H 2 O mol wt: SO 3 H linear alkylbenzenesulfonic acid 326 (average C 12 chain) SO 3 Na sodium alkylbenzene- 348 (average C 12 chain)

7 G Page 7 ENVIRONMENTAL ISSUES LAS has been safely consumed in large volumes throughout the developed world for over 25 years.* Although its use was once questioned in Western Europe because of its lack of biodegradability under anaerobic conditions, LAS is disposed of under aerobic conditions (i.e., sewage treatment plants), where it does fully biodegrade. In any case, no legislation adversely affecting the use of LAS is expected in Western Europe or elsewhere, and it is expected to remain the world s largest surfactant used in detergents for many years. According to a recent comprehensive risk assessment study carried out by the Netherlands government, the usage of LAS in laundry detergent powders does not involve any significant environmental risk. LAS, as well as other large-volume surfactants, are efficiently (over 99%) removed in the sewage treatment systems. Similar conclusions were included in the end-of-year report of Britain s Department of the Environment. This report states that LAS is readily biodegradable and its use in consumer products poses no hazard to human health or the environment. The EU s regulatory committee on ecolabeling recently approved detergents based on LAS, and they will now qualify for the EU ecolabel. UNITED STATES PRODUCING COMPANIES SUPPLY AND DEMAND BY REGION The companies listed in the following table produce linear alkylbenzene sulfonic acid by sulfonation of alkylbenzene. Most of these sulfonators also neutralize at least a portion of their output to produce salts. Only one of the domestic sulfonators Vista Chemical Company has captive supplies of linear alkylbenzene. In addition to the companies listed in the table, other companies produce salts from purchased acids. According to industry sources, there are many such companies, and most use these salts captively. A definitive identification of U.S. capacity dedicated to the sulfonation of linear alkylbenzene cannot be made since chemicals other than linear alkylbenzene (e.g., alpha-olefins) can also be sulfonated in some of the same equipment. Also, facilities using SO 3 -air processes are often used for the sulfation of alcohols and alcohol ethoxylates. Therefore, the annual capacity figures given below represent only potential production capacity for LAS, provided that capacity was devoted solely to this task. * Further information documenting biodegradation of LAS may be found in A. M. Nielsen et al., LAS Biodegradation: Ultimate Fate of Alkyl and Ring Carbon, paper presented at the 1980 Annual Meeting of the Soap and Detergent Association, January 31-February 3, 1980, Boca Raton, Florida.

8 H Page 8 >>U.S. Producers of LAS<< Company and Plant Location Annual Capacity as of September 1995 a (millions of pounds) Sulfonation Process Products Albright & Wilson Americas Blue Island, IL b 90 SO 3 -air BIT Manufacturing, Inc. Copperhill, TN na na Sodium salt Colgate-Palmolive Company Cambridge, OH 90 SO 3 -air Sodium salt Jeffersonville, OH 80 The Dial Corp. St. Louis, MO 90 SO 3 -air Acid and sodium salt Huish Chemical Company Riverton, WY 18 Oleum Acid and sodium salt Lever Brothers Company Baltimore, MD 75 SO 3 -air Acid and sodium salt Hammond, IN 30 SO 3 -air Acid and sodium salt Pilot Chemical Company Avenel, NJ 25 SO 3 -SO 2 Sodium salt Lockland, OH Middletown, OH Middletown, OH SO 3 -SO 2 SO 3 -SO 2 SO 3 -air Acid; dimethylamine, isopropylamine, triethanolamine and sodium salts The Procter & Gamble Company c Procter & Gamble Chemicals Alexandria, LA Augusta, GA St. Bernard, OH Stepan Company Anaheim, CA Fieldsboro, NJ Millsdale, IL Winder, GA 380 Oleum Sodium salt 1,300 SO3-air Acid; isopropylamine, triethanolamine, sodium, calcium and potassium salts Winn-Dixie Stores, Inc. Astor Products Blue Arrow Division Jacksonville, FL 10 Oleum Acid and sodium salt Witco Corporation c Oleochemicals Group Houston, TX 75 SO 3 -air Acid; calcium, triethanolamine, diethanolamine, sodium and ammonium salts Total 2,288 a. Theoretical capacity, if production were solely devoted to 100% active linear alkylbenzene sulfonic acid. b. Acquired from Witco Corp. in late c. The sulfonation plants and capacities listed for The Procter & Gamble Co. and Witco Corp. do not include these companies chlorosulfonic acid sulfonation units, since these units are not used to make LAS. Also excluded are Procter &

9 I Page 9 Gamble s SO3-air plants at Baltimore, Maryland and Kansas City, Kansas, which do not produce LAS. CEH estimates. Since 1993, three producers have terminated production of LAS and other significant changes have occurred. These are listed below. BIT Manufacturing, Inc. began producing LAS at its plant, which previously produced only branched alkylbenzene sulfonates (BAS). Its production of LAS is believed to be very small. Colgate-Palmolive shut down its Kansas City, Kansas and Jeffersonville, Indiana oleum and SO 3 - air units. However, the company added a new SO 3 -air unit at Cambridge, Ohio. The Dial Corp. shut down its oleum unit at Bristol, Pennsylvania, but increased its SO 3 -air capacity at St. Louis, Missouri. Kleenbrite Laboratories Inc. shut down its oleum sulfonation unit at Brockport, New York. Pilot Chemical Company added a new million pound-per-year SO 3 -air unit at Middletown, Ohio in The Procter & Gamble Company closed its Quincy, Massachusetts and St. Bernard, Ohio oleum sulfonation units and consolidated production at the other three sites. Its SO 3 units at Ivorydale, Ohio and Kansas City, Kansas continue to operate but have not produced LAS for many years. Instead, the plants produce alcohol ether sulfates; consequently, these plant sites have been dropped from the list. Stepan Company increased its capacity for producing LAS from 900 million to 1,300 million pounds per year. Theochem Laboratories, Inc. shut down its oleum sulfonation unit at Atlanta, Georgia. Safeway Stores, Incorporated closed its Oakland, California oleum unit. Lever Brothers Company shut down its last oleum sulfonation unit at Los Angeles, California. Of the eleven producers listed in the table, six are household detergent manufacturers that internally consume most or all of their LAS production for detergents. The other five sell nearly all of their LAS in the merchant market, either as such or in surfactant blends. Four merchant producers that account for at least 95% of the merchant market (including LAS-containing blends of surfactants sold to detergent manufacturers) are Pilot Chemical Company, Stepan Company, Vista Chemical Company and Witco Corporation. Of these four, Stepan is by far the largest, as shown in the following figure:

10 J Page 10 U.S. Production of LAS by Manufacturer 1994 Vista (8%) Witco (4%) Pilot (4%) Stepan (26%) Detergent Manufacturers for Captive Use (58%) SALIENT STATISTICS The following graph and table provide estimates of the U.S. supply/demand balance for LAS in recent years. >>U.S. Supply/Demand for LAS<< (millions of pounds) Production Imports Exports a Consumption Apparent b neg neg neg neg c 802 neg 6 794

11 K Page 11 a. Exports are only for LAS as such; any LAS exported in detergent formulations is not included. b. About 90% of the LAS imports in 1985 were probably accounted for by LAScontaining laundry detergent products imported from Canada. Imports in subsequent years were of LAS itself. c. Data includes United States and Canada. CEH estimates. The value of the 1994 U.S. production of LAS is estimated at $ million. Since 1966, the U.S. International Trade Commission (USITC) has reported data on the production and sales of alkylbenzene sulfonates. Data include linear alkylbenzene sulfonic acids and salts and branched alkylbenzene sulfonic acids and salts (BAS). Production of the latter is estimated at million pounds in recent years. However, an analysis of the data suggests that the total production reported by the USITC is probably well below actual production levels. Some of the known producers are not cited by the USITC as having reported production of LAS during recent years. In addition, the level of production of the LAS precursor, linear alkylbenzene (LAB), and the apparent consumption of LAS in household and industrial detergents suggest that LAS production was considerably greater than reported by the USITC. For example, the 1990 production figure reported by the USITC was only about 662 million pounds for LAS and BAS combined, whereas the CEH estimate for that year is 906 million pounds for LAS alone. The USITC data also provide a breakdown of U.S. production and sales of LAS and BAS by each salt, which may reflect the relative production and sales of these salts. The 1993 data reported by the USITC are listed in the following table: Reported U.S. Production and Sales of Alkylbenzene Sulfonic Acid and Salts 1993 a (millions of pounds, 100% active basis) Production Sales Sodium Dodecylbenzenesulfonate Dodecylbenzenesulfonic Acid Triethanolamine Dodecylbenzenesulfonate Calcium Dodecylbenzenesulfonate a. Data are presented as reported in the source but are believed to be less than actual production and sales levels. Also, dodecylbenzenesulfonic acid is all converted to its salts, mainly sodium, so a great deal of double-counting is present in the data. Synthetic Organic Chemicals, U.S. Production and Sales, U.S. International Trade Commission.

12 L Page 12 1,000 Millions of Pounds U.S. Supply/Demand for LAS Thousands of Metric Tons Production Imports Exports Following the large-scale introduction of LAS in the mid-1960s, its production increased as it replaced the slower-to-biodegrade BAS, and the use of light-duty liquid detergents using LAS grew rapidly. Production was relatively stable through the early 1970s, except for recessionary 1971 and During 1976, production of LAS recovered, and it steadily increased through 1978 in response to the growing market for laundry liquids and nonphosphate laundry powders containing high LAS levels. Production declined sharply in as a result of several major laundry detergent reformulations in which LAS levels were greatly reduced. Production generally increased during following the introduction of several household detergents with high LAS levels and strong growth in the household laundry liquid market. However, the production of LAS declined again in as a result of many detergent reformulations that reduced the LAS content of these products. Indeed, the 1994 LAS production level was the lowest since See the following section for a more detailed analysis of the issues that account for these reformulations and the fluctuating demand for LAS by the detergent industry over the last two decades.

13 M Page 13 CONSUMPTION About 85-90% of the U.S. consumption of LAS is in household detergents, including laundry detergents (both powders and liquids), dishwashing detergents and various general-purpose household cleaners. The balance of the LAS consumption is in industrial, institutional and commercial cleaners, as well as in a number of diverse industrial applications, where its use is not related to its cleaning properties. The following table provides a breakdown of U.S. consumption of LAS by end use: >>U.S. Consumption of LAS by End Use<< (millions of pounds) Household Products Heavy-Duty Laundry Powders Heavy-Duty Laundry Liquids Light-Duty (Dishwashing) Liquids Miscellaneous Household Cleaners Other a Total b a. Includes all nonhousehold uses (i.e., industrial, institutional and commercial uses) and may include producer inventory adjustments. b. Data includes United States and Canada. CEH estimates. The following table presents estimates of the 1994 U.S. consumption of LAS by end use, the projected consumption in 1999, and the average annual rates of change for the major categories of end use:

14 N Page 14 U.S. Consumption of LAS (millions of pounds) Average Annual Growth Rate, (percent) Household Products Heavy-Duty Laundry Powders Heavy-Duty Laundry Liquids Light-Duty Liquids Miscellaneous Household Cleaners Industrial, Institutional and Commercial Applications a Total % a. Category may include some inventory adjustments by LAS producers. CEH estimates. The 1994 LAS consumption was 33% below the peak level in This drop largely reflected reformulations that were unfavorable to LAS. The following sections present an analysis of each end-use area. Household Products About 540 million pounds of LAS were consumed in U.S. household detergents in 1994, compared with 820 million pounds in the peak year of From the late 1960s, when it replaced BAS, until 1993, LAS was the largest-volume surfactant consumed in household detergents. In 1994, however, alcohol ether sulfates (AES) replaced LAS as the largest-volume anionic surfactants used in household detergents. The issues that led to this decline in LAS usage are described in considerable detail in the subsequent sections on the various household detergent types. Nevertheless, LAS remains a major surfactant in household detergents. Most synthetic detergent formulations are fairly complex mixtures, and manufacturers have developed considerable sophistication in varying the contents to achieve the desired performance at the lowest possible cost. The choice of which surfactant to employ is based on the advertising claims the manufacturer wishes to make for a product and on cost/performance considerations that depend upon its performance in the formulated product and the ease of processing of the surfactant in combination with other ingredients in the formulation. The characteristics that have contributed to the widespread use of LAS include the following: excellent surfactant properties, low cost relative to alternative surfactants, ease of processing into nonhydrous powders when spray-dried, favorable solubility characteristics for use in liquid formulations, compatibility with other surface-active agents used in mixed-actives systems, medium to high sudsing characteristics in formulations, and long-accepted biodegradability and favorable performance under toxicological scrutiny. The dominant U.S. producers of household detergents (and consequently the largest U.S. consumers of LAS) are The Procter & Gamble Company (P&G), Lever Brothers Company, Colgate-Palmolive Company, The Dial Corp. (producer of Purex products), Huish Chemical Company, and Church & Dwight Co., Inc. (Arm & Hammer products). Smaller household detergent producers using LAS

15 O Page 15 include DeSoto, Inc.; Amway Corporation; Astor Products; the Consumer Products Division of Dow Chemical U.S.A.; Kleenbrite Laboratories Inc.; and USA Detergents, Incorporated. The major manufacturers of household products produce and captively consume LAS, although some of these manufacturers also purchase additional quantities of LAS from merchant suppliers. The latter transactions usually reflect the capacity limitations of some manufacturers for producing LAS using the SO 3 -air process, which is preferred for making LAS that is subsequently used in liquid products (see the MANUFACTURING PROCESSES section of this report). Many smaller detergent producers purchase all of their LAS from merchant suppliers. The major household product categories consuming large volumes of LAS are heavy-duty laundry powders, heavy-duty laundry liquids and light-duty dishwashing liquids. (See the CEH Surfactants, Household Detergents and Their Raw Materials marketing research report for a discussion of the formulation of these products.) Smaller volumes of LAS are also consumed in a variety of generalpurpose household cleaners. The individual household detergent categories and their consumption of LAS are discussed in the following sections. Heavy-duty laundry detergents (powders and liquids) U.S. consumption of LAS in household laundry detergents amounted to about 438 million pounds in This represents a decline of almost 130 million pounds since 1993, all of which is accounted for by the removal of LAS from the laundry liquids of P&G. This formulation change no doubt reflected a number of considerations, one of which was a recognition of the tendency of high levels of LAS to deactivate enzymes in liquid systems. This and other issues are discussed later in this section. Future growth for LAS depends upon both the growth and the composition (e.g., powders vs. liquids) of the U.S. laundry market and on the competition between LAS and other surfactants. The future design of new energy-efficient washing machines will also have a big impact, but this will likely have no significant effect until the year The U.S. market includes both powder and liquid laundry products, with the liquids accounting for almost 40% on a poundage basis. This contrasts sharply with other world areas, where liquids account for only a very small share. There has been very little growth in the U.S. consumption of laundry powders since 1979; however, the volume of liquid laundry detergents consumed tripled between 1979 and This growth was greatly slowed by the introduction of compact laundry powders in 1991, but this may change as the concentrated liquid laundry detergents, which were widely introduced in 1993, become more popular. Furthermore, the U.S. Environmental Protection Agency (EPA) is considering new, lower energy consumption guidelines for future washing machines that are expected to reach the market in the next century. Since these machines must use less hot water, most industry sources believe they will probably require liquid detergents to effect a rapid and complete solution. The growing sales of laundry liquids were once a welcome development to LAB and LAS producers, since the surfactant levels, including those of LAS, were considerably higher in the liquids than in the powders. Overall surfactant levels continue to be higher in liquids, but since the P&G reformulations previously mentioned, the average level of LAS is now lower in liquids than in powders. Thus, any future growth for liquids at the expense of powders will no longer benefit LAS. Furthermore, the low-energy-consuming machines will also require high agitation, which will require low-foaming surfactants. LAS is a high- to mediumfoaming surfactant, and its use level might be limited in the new machines, although various defoaming ingredients might be used to overcome this problem.

16 P Page 16 The U.S. laundry market is expected to grow at an average annual rate of about 2.3% (washload basis) over the period. During the 1980s, the overall growth in the U.S. market for laundry detergents (powders and liquids) was much larger and greater than the estimates of many industry sources. The lower estimates were based largely on annual sales estimates provided by national surveys that were in turn based on sales of detergents in supermarkets. These sales surveys often neglect the increasing sales of laundry and other household products by mass merchandisers or warehouse consumer outlets. Since these outlets generally offer only a few brands at greatly reduced prices, detergent manufacturers must offer the lowest possible prices to secure shelf space at these outlets. This development has caused major restructuring in the detergent industry and intensified manufacturers efforts to reduce formulation costs. Thus, one of the most important considerations in the future consumption of LAS in home laundry products is the relative price for LAS compared with prices for the alcohol-based surfactants. LAS is derived from benzene and n-paraffins, both of which are in turn derived from petroleum. Petroleum prices declined significantly in 1986 and have remained relatively low since then, leading to comparatively low and reasonably stable prices for benzene and n-paraffins. In contrast, the alcoholbased surfactants are produced largely from ethylene, which is derived mainly from natural gas liquids in the United States. Prices for ethylene have been more volatile in recent years. Indeed, ethylene and ethylene oxide prices increased sharply in , reflecting strong demand for ethylene in plastics and other markets, along with a shortage in ethylene capacity. Prices for these products subsequently declined in recessionary , but rose again in 1994 and 1995 as the U.S. economy grew strongly. Prices for ethylene declined somewhat in late 1995, but prices for ethylene oxide, which is used to make the alcohol ethoxylates (AE) and alcohol ether sulfates (AES), are expected to remain strong for some time. Although ethylene prices will continue to cycle in the future, both LAS and the alcohol-based surfactants are expected to remain highly competitive on a cost/performance basis for the foreseeable future. On relative performance, AE has lower hard-water sensitivity than LAS, a consideration that is especially important in liquid laundry detergents, all of which lack an effective builder (i.e., a sequestrant for hard water ions). However, LAS is more readily processed into powders than AE. LAS is generally considered more effective than AE on heavy particulate soils (e.g., clays), whereas AE is more effective on body oil stains. Consequently, most manufacturers prefer to use a combination of both to obtain the optimum performance for average washing conditions. Overall, these performance considerations suggest that LAS will continue to be a cost-effective surfactant, especially in powders where its processing characteristics are an advantage and where it has no adverse impact on enzyme stability. LAS is also higher foaming than AE, which some consumers perceive as providing better cleaning. However, high foaming is a disadvantage in horizontal axis, rotating drum washers, where high foam levels would result in overflow problems. This property could be a major disadvantage for LAS in the new low-energy washing machines, which could use this design or another that will likely require high agitation. Some sources believe that defoamers can control this effect, but it is still likely to be a disadvantage for LAS. The ultimate impact of this future development is uncertain, but it should not have any significant impact until after the year A third consideration in assessing the future growth of LAS is the degree to which enzymes are used in liquid detergents. Certain enzymes assist the action of surfactants by promoting the hydrolysis of protein and starch stains. Others contribute to preserving the appearance of cotton fabrics after repeated washing. Some detergent manufacturers are not convinced that the high costs of enzymes are justified and believe consumers are unaware of any improved performance they might contribute. However, the two largest detergent manufacturers (P&G and Lever Bothers) do use them. Anionic surfactants in solution are

17 Q Page 17 known to inactivate enzymes over time, but the adverse impact of LAS is greater than with other anionics. As the level and complexity of the enzyme systems used has increased, this problem has become more apparent. Although enzyme and LAB manufacturers have sought a solution, none is known at this time. P&G s reformulation partly reflected this problem, but also the economic advantage of using its captive production capability for methyl esters of fatty acids at its plant in Malaysia. These esters are a key raw material for making the N-alkylglucosamide (AGA) and AES surfactants that replaced the LAS content of P&G s liquid laundry detergents. There could be further large reductions in LAS if Lever Brothers also reduced the LAS level in its liquid products. However, Lever Brothers lacks the captive raw material position of P&G and would not have the same economic advantage in reformulating its liquids. Thus, all manufacturers of liquid laundry detergents using LAS and enzymes must carefully balance the benefits of each and determine what their optimum levels are. Although LAS is vulnerable to replacement by other surfactants in laundry liquids incorporating enzymes, a precipitous decline in LAS consumption in these products seems unlikely. A final consideration is the threat to LAS posed by environmental concerns, including concerns about the tetralin content of the raw material, LAB; the nonbiodegradability of LAS under anaerobic conditions; and its derivation from nonnatural (i.e., petroleum) sources, which are not renewable. LAB manufacturers have already reduced the tetralin content of LAB to 1% or less in nearly all of the product sold to the major manufacturers and have provided evidence of the rapid biodegradability of the tetralins that remain. Although LAS is not biodegradable under anaerobic conditions, this is also true of several other surfactants commonly used, as well as many other chemicals. Furthermore, only a small percentage of the LAS in the environment is finally destined for anaerobic conditions; LAS is largely disposed of in sewage treatment plants under aerobic conditions. Most sources agree that the large-scale use of LAS for over 25 years without any observed problem is the best evidence of its apparent safety. The issue of the preferability of natural and renewable raw material sources has been extensively debated. It is widely recognized that even surfactants based on natural (i.e., vegetable) sources require subsequent chemical processing that blurs any distinction between natural and synthetic products. Indeed, one life-cycle analysis study showed that the manufacture of a naturally derived surfactant (an alpha-sulfo methyl coconut fatty acid ester) had a more adverse impact on the environment than the production of LAS. Unless future studies produce different results, this issue has only an emotional appeal, rather than one that is based on strong environmental evidence. The use of LAS in laundry powders should increase with market growth of the product over the period. The consumption of LAS in liquid laundry products will decrease somewhat over the same period as a result of the enzyme compatibility problems previously described. Overall, LAS consumption in laundry detergents will be flat over the period. Historical LAS consumption patterns Historically, the U.S. consumption of LAS in laundry detergents grew rapidly in the late 1960s, as it quickly replaced the less readily biodegradable BAS in these products. By 1969, this substitution was complete, and consumption of LAS grew more slowly, until it increased dramatically in the late 1970s as a result of two major developments. The first was the rapid growth in the use of laundry liquids (which generally use higher surfactant levels than do powders). The second was the major reduction in the phosphate levels of detergents, which initially required higher surfactant levels to maintain acceptable performance. The phosphate reduction reflected both the higher cost of phosphates and government restrictions on their use in certain regions of the country. LAS was the surfactant of choice for most

18 R Page 18 producers in the late 1970s, and the volume of its consumption in laundry detergents reached a level of 519 million pounds in When raw material costs began to rise as a result of the second world oil crisis in 1979, detergent manufacturers began to reduce the cost of their detergent formulations by lowering the level of LAS and using more of the alcohol-based surfactants. The price of ethylene (from which the alcohol-based surfactants are largely derived) had not risen as rapidly as n-paraffins and benzene (from which LAS is derived and which are tied directly to crude oil prices). As a result, the consumption of LAS in laundry products fell to only 365 million pounds in 1983 or 154 million pounds below the prior peak level in Consumption of LAS increased significantly in the mid-1980s as a result of lower crude oil prices and the successful introduction of several new laundry products containing high levels of LAS, including P&G s Liquid Tide and Lever Brothers Surf laundry powder. Consumption continued to increase in the late 1980s as a result of the growth in demand for laundry liquids and the subsequent introduction of compact laundry powders that detergent manufacturers initially found easier to make from LAS than from other surfactants. Thus, both production and consumption of LAS set new record levels in 1988 and again in Consumption declined during the period as previously described. Light-duty liquid detergents Nearly 85 million pounds of LAS were consumed in light-duty liquid detergents in These products are designed primarily for hand-washing of dinnerware and, to a far lesser extent, for hand-laundering of fine fabrics and hosiery. Most light-duty detergents use LAS in combination with lower levels of alcohol ether sulfates (AES) and fatty alkanolamides (FAA). Alternatively, Procter & Gamble has consistently used higher levels of AES, in combination with other surfactants (e.g., alcohol sulfates, fatty amine oxides, amphoterics, and n-alkylglucosamides), and not used any LAS in its dishwashing liquids. This approach may be too expensive for other producers, but Procter & Gamble has an economic advantage, since it has a basic position in fatty amine oxides and also in detergent alcohols, from which AES is derived. The sales of the light-duty liquids have shown very little growth over the last ten years. The main reason has been the increasing use of automatic dishwashers, which use a different type of detergent. Automatic dishwashing detergents are based largely on inorganic builders (e.g., phosphates and silicates) and use only very low levels of specialty organic surfactants. From 1982 through 1992, the consumption of LAS in light-duty detergents had been fairly stable. However, consumption fell sharply in 1993 and 1994, as several large manufacturers increased the use of milder surfactants, such as AES, alkylpolyglucosides (APG), and amphoterics, and lowered their LAS levels. As prices of some of these milder surfactants, especially AES, began to increase in 1994 and 1995, some detergent producers may switch back to LAS. However, Lever Brothers reportedly began using alpha-sulfo methyl esters in its dishwashing liquids, and this reformulation may further lower the levels of LAS. Alcohol ethoxylates and alkylphenol ethoxylates cannot be employed in these products at significant levels because of the high level of skin irritation that would result from their use. Thus, detergent producers had fewer formulation options in hand-dishwashing liquids than in laundry detergents. Until 1993, therefore, the consumption of LAS in this market tended to reflect the growth in the overall use of dishwashing liquids and the market share of the light-duty detergents that use the LAS/AES/FAA formulation. This distribution had been more affected by the success of the advertising promotions of the major producers than by any raw material cost considerations.

19 S Page 19 The greater emphasis on mildness that began in the 1990s led to the use of amphoterics and other mild cosurfactants, and this approach may become more common in the future as manufacturers seek to promote greater mildness as a product attribute. This trend will probably further reduce future LAS consumption in this market. However, LAS still has a significant cost advantage over most alternative surfactants. Thus, the consumption of LAS in dishwashing liquids is likely to decline only slightly, at an average annual rate of 1% over the period. This projection reflects the expectation of little growth in the sales of the light-duty liquids and some product reformulations that are disadvantageous to LAS. The reformulations are likely to involve the greater use of milder surfactants in place of LAS. Miscellaneous household cleaners LAS is frequently present at low levels in numerous household cleaners. Inorganic salts and solvents are usually the major ingredients, and other surfactants are often used instead of LAS. Examples of the product categories and brand names that may contain LAS include floor cleaning powders (e.g., Spic and Span ) and heavy-duty hard-surface cleansers (e.g., Mr. Clean ). Small amounts of LAS may be used in several other household cleaning products. According to industry sources, specialty products such as some floor cleaners and laundry presoaks and prespotters annually consume small amounts of LAS. An estimated 18.5 million pounds of LAS were consumed in these products in There will probably be a 1.5% average annual growth rate for these products and a 1.0% average annual growth in the LAS consumed in them for the period. Industrial, Institutional and Commercial Applications In 1994, almost 70 million pounds of LAS were consumed in nonhousehold markets, mainly industrial, institutional and commercial products and processes. This estimate reflects the difference between estimates of the total volume of LAS consumption and the volume consumed in household uses. As such, it can include some changes in customer inventories of LAS (both household and nonhousehold) and may be subject to a much larger error than the other categories described. Thus, the reader should exercise some caution in interpreting the significance of changes in the consumption estimates for this category over time. Since nonhousehold markets for LAS are numerous and widely dispersed through industrial, institutional and commercial establishments, they are difficult to quantify. This category includes nonhousehold markets in which LAS is used in formulated cleaning products. Examples include commercial laundries, commercial and institutional restaurants using formulated hand-dishwashing liquids, janitorial cleaners used for offices and institutions, and transportation vehicle washing establishments. This category also includes applications where the performance properties of LAS other than its basic detergency are important (e.g., emulsification of agricultural herbicides or of monomers in polymer processing). Although some developmental research on the use of LAS in tertiary oil recovery operations was conducted (especially in 1981, when 3-5 million pounds were consumed in this use), it is unlikely that any significant quantities of LAS have recently been or will be consumed in this application because of its higher cost compared with that of petroleum sulfonates and the outlook for continued low crude oil prices.

20 T Page 20 Other small or potential applications of LAS include sludge dispersion and its use in construction wallboard. Growth in the consumption of LAS in all nonhousehold applications is expected to increase at an average annual rate of 1% over the period. PRICE Market prices for LAS have declined significantly during the period. Average prices for large-volume purchases are well below list prices, and are probably in the $ per-pound (100% active basis) range. The following table presents typical list price histories for linear alkylbenzene sulfonic acids and salts: >>U.S. List Prices for Linear Alkylbenzene Sulfonic Acid and Salts a << (cents per pound) Acid b Sodium Salt c Salt d Triethanolamine r

21 U Page e a. Prices shown through 1971 and for are list prices on or about July 1 of the year indicated; data for represent list prices as of December. The 1976 list prices became effective October 1, b % active basis. c. 100% active basis. d. 60% active basis. e. 60% active basis. CEH estimates. Since 1966, the U.S. International Trade Commission has reported unit sales value data (i.e., average sales value) for sodium, calcium and triethanolamine dodecylbenzene sulfonates. These values include both the branched (BAS) and linear (LAS) products. Since 1971, linear alkylbenzene sulfonic acid and salts are estimated to have accounted for over 90% of the total volume of sulfonates used to calculate these unit sales value data. The reported value of the sulfonic acid appears to be far below realistic averages in recent years, and the reported value of the sodium salt appears to be much higher than likely for These data are listed in the following table: U.S. Unit Sales Values for Alkylbenzene Sulfonates a (cents per pound) Dodecylbenzenesulfonates Total Alkylbenzene Acid Sodium Calcium Triethanolamine Sulfonates b