“Green” Is the Development Trend for Anionic Surfactants

By Luo Yi and Luo Xiquan from China Research Institute of Daily Chemical Industry, and Fang Yinjun from Zhejiang Zanyu Technology Co., Ltd

Constant growth of output

Table 1 lists the supply and consumption of surfactants in China during 2007 - 2011, based on the China Cleaning Industry Association's statistics (counting on 100% active ingredient) and the General Administration of Customs' import and export data, and amended and supplemented according to market research data from the same time. The data cited here does not include the bulk commodities like petroleum sulfonate, lignin sulfonate, tea saponin, etc.

Table 1 Supply and Consumption of Surfactants in China during 2007 to 2011    (thousand tons)
Year    Total output    Net import volume    Apparent consumption    YoY growth of apparent consumption (%)    Proportion of a-SAA in the total output (%)
2007    1 270    193    1 470    14.8    71.9
2008    1 250    158    1 410    -0.4    75.9
2009    1 490    196    1 690    20.0    68.7
2010    1 600    86    1 690    0    62.4
2011    1 700    6    1 710    1.2    59.2

Source: China Cleaning Industry Association and the General Administration of Customs

   During 2008-2011, in addition to meeting domestic demand, China’s anionic surfactants (a-SAA) also had surplus output for exports at the same time. Both the output and apparent consumption of anionic surfactants were around 1.0 million tons. Table 2 lists the supply and consumption of anionic surfactants in China during 2008 to 2011.
Table 2 Supply and Consumption of Anionic Surfactants in China during 2008 to 2011    (thousand tons)
Year    Import volume    Export volume    Net import volume    Output        Apparent consumption    YoY growth of apparent consumption (%)
2008    43.1    65.5    -22.5    949    926    0.5
2009    50.3    63.1    -12.8    1 023    1 010    9.1
2010    54.8    78.8    -24.0    998    974    -3.5
2011    54.2    99.3    -45.1    1 006    961    -1.3
Source: China Cleaning Industry Association and the General Administration of Customs


Production and market situation of major anionic surfactants

1. LAS

Linear alkylbenzene sulfonate (LAS), which is the anionic surfactant with the largest output, is the main surfactant used in household and industrial cleaning agents. The production and consumption of LAS have expanded constantly, and the product quality has been upgraded continually. Due to the large number of LAS enterprises, it is difficult to make complete statistics. Whereas the consumption of linear alkyl benzene (LAB) is easy to count, so the LAS output estimated by using the apparent consumption of LAB (1 ton of LAB can produce 1.34 tons of LAS) is closer to the actual output.
   China’s apparent consumption of LAB is 450 thousand - 500 thousand tons and the LAS output is 600 thousand - 660 thousand tons. Not only are the quantity and quality of China’s LAB fully able to meet the domestic demand, but the volume of LAB exported from China has also increased year-on-year. However, the consumption proportion of LAS in China will reduce due to the constant rise of petroleum prices, increasing ecological concerns and the emergence of products with more advantages and competitiveness such as alcohol-type surfactants, fatty acid methyl ester sulfonate (MES) and sodium alpha-olefin sulfonate (AOS). At present, 500 000 t/a of LAB capacity can meet the domestic demand, however, the 150 000 t/a newly expanded LAB capacity has recently been completed, the excess LAB supply will appear in the domestic market and the resulting oversupply will be solved only by expanding the international market or developing new uses.
   
2. Alcohol-type anionic surfactants

Alcohol-type anionic surfactants refers to sodium salts (such as AS and AES) and ammonium salts (such as LSA and AESA) of fatty alcohols (ethers) produced by sulfating fatty alcohols or fatty alcohol ethers with SO3 and then neutralizing the resultants with NaOH or NH4OH. China's output of major alcohol-type anionic surfactants in recent years is listed in Table 3.
Table 3 Outputs of major alcohol-type anionic surfactants in China from 2007 to 2011 (thousand tons)
Year    AES    AS    AESA    LSA    Total
2007    198.6    20.8    15.2    10.8    245.4
2008    232.7    17.8    12.6    9.3    272.4
2009    282.3    23.8    17.7    11.0    334.8
2010    233.9    24.8    11.3    8.0    278.0
2011    241.9    20.5    8.4    7.9    278.8
Source: China Cleaning Industry Association

   At present, in anionic surfactants, sodium fatty alcohol polyoxyethylene ether sulfate (AES) is the second largest sulfonated or sulfated product. It is also a variety of alcohol-type anionic surfactants with the largest output. In China’s enterprises that have around 120 sets of running SO3 sulfonated/sulfated units, less than 20 enterprises can produce AES and more than a dozen enterprises have an annual output of over 10 thousand tons. Output of China’s major AES producers in recent years is listed in Table 4.
Table 4 Output of China’s major AES producers in recent years (thousand tons)
Year    2007    2008    2009    2010    2011
Zhejiang Zanyu Technology Co., Ltd    36.8    34.6    58.5    79.9    82.3
Sinolight Chemicals Co., Ltd    18.6    23.0    33.9    29.0    23.4
Hunan Resun-Auway Industrial Co., Ltd    22.4    21.4    30.2    36.4    44.1
Tianjin Angel Chemicals Group Co., Ltd    13.6    20.3    20.9    20.3    22.8
Total    199.0    225.0    271.0    236.0    242.0
Source: China Cleaning Industry Association

   Zhejiang Zanyu Technology Co., Ltd, which is the largest AES producer in China, has developed rapidly in recent years, and its output continued to maintain the first place during 2007-2011.
   Two 5 t/h sulfonated production lines with AES as main product recently constructed by Liaoning Huaxing Group will soon be put into operation, so competition will be fiercer in the AES market.

3. AOS

AOS is a variety of anionic surfactants produced through sulfonating alpha olefin with S03, neutralization and hydrolysis reactions. Due to its good foaming property, water softening property, biological degradability and detergency, AOS is an ideal raw material for the production of washing powder, composite soap, dishwashing detergent, shampoo, bath lotion, etc. At present, China has 5 major AOS producers, and the output of China’s major AOS producers in recent years is listed in Table 5.
Table 5 Output of China’s major AOS producers during 2008-2011 (tons)
Producer    2008    2009    2010    2011
Sinolight Materials Corporation     23 559    29 207    24 401    27 105
Zhejiang Zanyu Technology Co., Ltd    9 191    10 749    12 433    20 514
Hunan Resun-Auway Industrial Co., Ltd    6 635    6 329    5 769    7 955
Nafine Chemical Industry Group Co., Ltd    8 936    5 695    5 431    4 111
Shandong Jujin Chemical Industry Co., Ltd    -    -    -    3 000
Total    48 321    51 980    48 034    62 685

Source: China Cleaning Industry Association

   In recent years, because of its good performance and a low-price marketing strategy, the performance/price ratio and competitiveness of AOS have been greatly enhanced, and
   AOS has good applications and rapid development in the domestic market. However, due to the tight supply and rising prices of alpha- C12-18 olefins, key raw materials for AOS production, caused by limited alpha- C12-18 olefins resources, AOS does not have the possibility of further rapid growth, and maintains only a relatively stable market share governed by the raw material supply.

4. MES

MES is a new natural surfactant product based on oil and fat that the sector is working to develop, and it has broad application prospects. It has excellent detergency, emulsification and solubilization, as well as easy biological degradation, good water softening property and is easy to rinse away. Compared with AES, AEO9 and CAB, MES has a significant price advantage. The price of MES is basically the same as that of LAS, AOS and 6501, and the performance/price ratio of MES is superior to that of LAS. Note that the raw materials are renewable resources. With the depletion and rising prices of petroleum resources, MES is expected to partially replace petroleum-based surfactants in line with the green environmental protection requirements and the overall development trends.
   The difficulty for realizing the mass production and commercial promotion of MES in China is subject to the production technology, machinery and formula application of MES, that is, controlling and improving the quality of products, in particular the product color, the content of disodium salt as well as the active substance drying process and equipment. In the formula application, MES has poor thermal stability under the alkaline conditions and it is difficult to adapt to the traditional washing powder production process. Therefore, powdery MES is added in post-mixture to produce washing powder. As a detergent surfactant, MES has advantages such as good compatibility with enzymes, excellent low temperature detergency and lime soap-dispersing power, and is suitable for preparation of low temperature detergents, enzyme concentrated powders, non-phosphorus detergents and soap products. At present, major MES producers in China are listed in Table 6.
Table 6 Major MES producers in China (thousand t/a)
Producer    Production capacity    Remarks
Zhejiang Zanyu Technology Co., Ltd    30    The first phase has been put into operation and developed by the company itself. The second phase 30 thousand t/a project is under construction and has  a sulfonated capacity of 3.8 t/h.
Shandong Jinlun Chemical Co., Ltd    5    It has a sulfonated capacity of 0.5 t/h, and cooperates with Jiangnan University to conduct R&D.
Guangzhou Qining Chemical Co., Ltd    36    The unit with a sulfonated capacity of 5 t/h imports technology from Chemithon of the United States and has been put into operation.
Zouping Fuhai Technology Development Co., Ltd    20    It has a sulfonated capacity of 2 t/h, produces 30% MES, and cooperates with Jiangnan University to conduct R&D.

Source: China Cleaning Industry Association

5. AEC

Fatty alcohol ether carboxylates (AEC) has rich, delicate and more durable foam, offers better skin compatibility, easily compounds with anionic and cationic surfactants. Especially used in personal care products (such as cleansing cream and shampoo), AEC can improve the compatibility of the formula and reduce the reactive inhibition between anionic surfactants and cationic surfactants. In addition, AEC has excellent water softening property and electrolyte resistance ability, can resist high temperature, cannot be decomposed under the temperature of 240 degrees centigrade and is suitable for use as a high temperature oil displacement agent.
   China's AEC is still in the initial development stage, and AEC is a hot variety in the recent development of the sector. China needs to continually conduct research and development for AEC, increase output and varieties, and expand the application fields. In the late 1980s, China Research Institute of Daily Chemical Industry began to conduct the development of a series of AEC products, and the bulk products were supplied to the market in the late 1990s. At present, a 1 000 t/a AEC unit has been completed and put into operation.

China’s surfactant sector will present new characteristics in the next few years

1. Constant growth of the output and demand

With the rapid development of the national economy, growth of the population and the improving standard of living, the detergents and cosmetics closely related to people's daily life will develop rapidly, and this will certainly promote the rapid development of surfactants – the main active components of detergent and cosmetics. In addition, the expansion of surfactants in various industrial application fields will greatly increase market demand for surfactants and stimulate the innovation and development of surfactants. With the output growth of surfactants in China and the acceleration of global economic integration, China’s export volume of surfactants will also increase rapidly.

2. Excess capacity and fierce competition

Although the overall consumption of surfactants in China will continue to climb steadily, the growth of enterprises’ capacity will be faster. It is expected that the production capacity of LAB units, fatty alcohol units and sulfonation units will be in surplus after two or three years. Therefore, competition in the surfactants market will be fiercer and industrial restructuring will be inevitable.

3. Specialization and large scale

In the past China’s surfactant production was small in scale and geographically scattered. Producers have gradually developed toward specialization and large-scale. At present, some enterprises are already large-scale or specialized, such as Synthetic Detergent Factory of PetroChina Fushun Petrochemical Co., Ltd, Sinopec Jinling Petrochemical Co., Ltd, Zhejiang Zanyu Technology Co., Ltd, Sinolight Chemicals Co., Ltd, Hunan Resun-Auway Industrial Co., Ltd and Liaoning Huaxing Group, and production will be further concentrated.

4. Expanding application fields

The surfactant application in China is no longer confined to the home uses, but has increasingly expanded to industrial sectors. In the future, China should continue to develop the applications of surfactants in the all sectors, especially high-tech, energy-saving, environmental protection, tertiary oil recovery, biological medicine, etc., and play the “industrial monosodium glutamate” role of surfactants.

5. Green is the development trend

Using natural oil and fat, starch, protein and sugar as raw materials to replace petrochemical raw materials to produce new-type green surfactants has become an inevitable trend and development direction.
The development for the green production technology and clean production process of surfactants will continue to stably develop toward using non-toxic and harmless raw materials, using atomic economic reaction in the manufacturing process, realizing zero discharge in the manufacturing process, reducing the reaction steps, shortening the process flow, saving energy, ensuring product safety, etc.

Laws and regulations attract more and more attention

The biological degradability, compatibility with environment, toxicity, mildness to human body, irritation and the content of harmful substances of surfactants have attracted extensive attention from all walks of life. For example, mild surfactants like APG, MES, AEC and polyglycerol esters of fatty acids have been developed. The relevant requirements and test method standards have been established for the content of dioxane in AES and the content of sodium chloroacetate in CAB. However, the restrictive requirements and corresponding test method standard for the content of sultone in AOS have not yet been established. The “No.648/2004/EC regulation of the European Parliament and the European Commission on detergents,” implemented by European Union (EU) in 2005, has also made strict provisions for the biological degradability of surfactants. The requirements have extended from the primary biological degradability to the ultimate biological degradability, and the primary biological degradation extent and ultimate biological degradation extent are required to be more than 80% and 60%, respectively. Products that do not pass the primary degradation test are not approved for sale in the market, and the products that do not pass the ultimate degradation test will be included in offbeat products. Therefore, the sector should pay great attention to the related laws and regulations of surfactants.