On December 4, 2017, China Rubber Industry Association (hereinafter referred to as CRIA) proposed the feedback opinions to the Ministry of Environmental Protection as for the problem of rubber mainstream accelerator and antioxidant products included in Entry 728~734 of Comprehensive Directory of Environmental Protection (Version 2017) (Exposure Draft) (hereinafter referred to as the Directory), and suggested to adjust the Directory according to the current overall production situation of rubber chemicals industry and use conditions of rubber industry: firstly withdraw the antioxidants 6PPD, TMQ and IPPD from the Directory; secondly, indicate that the accelerator MBT, CBS and DCBS products using cleaner production process do not belong to “GHW/GHF” products in the Directory.
According to information, on November 23, 2017, the website of the Ministry of Environmental Protection published Comprehensive Directory of Environmental Protection (Version 2017) (Exposure Draft), which covered 887 products included in high pollution or high environmental risk as well as various key equipment in environmental protection, with the period for exposure up to December 6. Major accelerator and antioxidant products in Chinese rubber chemicals industry at present were listed in the Directory, in which, Entry 728~730 included the accelerators MBT, CBS and DCBS as the products with high pollution and high environmental risk, and Entry 732~734 included the antioxidants 6PPD, TMQ and IPPD as the products with high environmental risk.
For this, CRIA called 8 major manufacturing enterprises of rubber accelerators and antioxidants to hold an emergency meeting on December 1, 2017 to analyze the safety and environmental protection conditions and use conditions in Chinese rubber industry of these two products and proposed the suggestions of the industry to the Ministry of Environmental Protection.
The “Listed” Products have Large Consumption and Have no Substitutes
Chinese chemicals industry began to vigorously promote cleaner production process from the start of this century and has proactively and gradually eliminated polluting products such as accelerator NOBS and antioxidant D, thus, at present, the processes of rubber chemical products advance in the poisonless and harmless direction in links from production process to waste treatment.
Gao Bo, general secretary of CRIA Chemical Specialized Committee, said, the output of the accelerator and antioxidant accounted for 63% of the total output of rubber chemicals. Among the accelerators, the output of sulfenamide accelerator reached 164,000 tons, accounting for 49.5% of the total accelerator output. Among the antioxidants, keto-amine and P-amine antioxidants were major anti-aging system products of tire stock, the output of amine antioxidant accounted for 90% of the total antioxidant output, in which the output of the antioxidant 6PPD, IPPD and TMQ products accounted for 83.2%. And these 6 rubber chemicals listed this time had no substitutes at present, so production limitation of these products would severely affect the market supply.
It is learned that since the nation reinforced the environmental protection in 2017, not only the price of the raw materials for chemicals sharply rises, but also the supply is intense, which causes intense supply and rising price of rubber chemicals, in addition, a batch of small enterprises not environmentally friendly stops production, short supply of rubber chemicals has severely affected normal production of Chinese rubber products such as tires. In addition, since the output of Chinese rubber chemicals accounts for about 75% of the total global output, the current tense supply trend even caused “panic” atmosphere worldwide.
Products Adopting Environmental Protection Process shall be Excluded
Liu Jingfu, general manager of Shandong Sunsine Chemical Co., Ltd., mentioned that through realization of cleaner production process, the overall technical level of domestic rubber chemicals industry was largely improved, and no safety and pollution accidents occurred in the industry at present.
The accelerator MBT is an irreplaceable raw materials for production of sulfenamide accelerator, and for healthy and sustainable development of rubber industry, its stable supply must be guaranteed; as the largest variety among the accelerator products, CBS not only is cheap and fine, but also is a primary amine accelerator not generating nitrosamine, and has been listed in the raw material directory of green tire of the Ministry of Industry and Information Technology.
Therefore, Liu Jingfu suggested deleting the accelerator MBT and CBS products using cleaner production process from the Directory, such as MBT produced with solvent method and pipeline continuous method; and CBS produced with hydrogen peroxide oxidation process and oxygen oxidation process.
Wang Shuhua, chairman of Kemai Chemical Co., Ltd., thought that the obvious development of cleaner process in domestic chemicals industry at present and the achievement that the total output of Chinese rubber chemicals accounted for over 75% of the global output were strong evidences of our insistence on development of green production for 30 years.
He mentioned that the rubber accelerator DCBS was the accelerator variety with the longest retarded vulcanization effect, although it was a secondary amine accelerator, it had high thermal stability and might generate little N-Nitrodicyclohexylamine during the rubber processing, however, German “Technical Rules of Hazardous Substances” TRGS 552 Regulations defined that this substance did not have carcinogenesis and its use process was safe. Meanwhile, in Regulation (EU) No. 1272/2008 (Classification, Labelling and Packaging of Substances and Mixtures), this product was included as general chemical instead of hazardous chemical; in 2017, the EU GLP Lab certified that this product had no pollution to the water environment, and canceled its label of grade 3 aquatic chronic pollution.
Wang Shuhua suggested that before the substitute of DCBS appeared, inclusion of this product in the Directory could be postponed, and excluding the products adopting cleaner production process such as hydrogen peroxide oxidation process and oxygen oxidation process.
As for the oxidant TMQ, Wang Shuhua explained that this product was a keto-amine antioxidant, was effective for protection of thermo-oxidative ageing and had extremely strong suppression effect on catalytic oxidation of the metal, it had low toxicity and had no substitute at present, thus he suggested deleting it from the Directory.
Xia Haiyang, manager of Science and Technology Management Department of Jiangsu Sinorgchem Co., Ltd., proposed that the cleaner production popularity of chemicals industry was constantly increased and the automatic and intelligent level was constantly improved, which had made the harm of the product on the environment constantly lowered.
He pointed out that 6PPD was a p-phenylenediamine antioxidant and an antiozonant and antioxidant for natural rubber and synthetic rubber, which had good protective effect for ozone cracking and flexural fatigue. 6PPD was a major antioxidant for tires, whose production process had realized “zero emission” of theoretical chemistry at present and obtained the second prize of National Scientific and Technological Progress Award. 6PPD was a top antioxidant at present, with zero emission and small environmental risk, thus he suggested deleting it from the Directory.
Meanwhile, Xia Haiyang mentioned that the antioxidant IPPD was the major product before 6PPD was put into use and had resigned from the leading post now, its output in 2016 was less than 10,000 tons; however, according to the analysis of its physical and chemical properties, it should not be listed in the products with “high environmental risk”.
Wang Zhiqiang, general manager of Willing New Materials Technology Co., Ltd., supplemented that Chinese rubber chemicals industry always firmly took the path of cleaner production process, even the EU leading in pollution control did not limit Chinese products, therefore, limit conditions should be added to the definition of high pollution and high environmental risk.
Zhu Hong, director of CRIA Technical and Economic Committee, also expressed the same opinion, technical progress in Chinese chemicals industry was widely recognized nationwide and multiple technical tests of domestic and foreign third party organizations had been passed. Meanwhile, the concentration of Chinese chemicals industry was largely improved and high-pollution enterprises not conforming to cleaner production process were eliminated to realize transformation and upgrading of the industry, thus we believed that the leading enterprises would lead the chemicals products to constantly progress in the direction of being green by virtue of self hard power.
Du Mengcheng, deputy general manager of Shandong Yanggu Huatai Chemical Co., Ltd., proposed that the industry should combine to start from the products of self enterprise, insist on green production and constantly carry out technical tackling of new process of cleaner production.
The representatives of the enterprises such as Shandong Stair Chemical & Technology Co., Ltd., SINOPEC Nanjing Chemical Industries Co., Ltd and Henan Kailun Chemical Co., Ltd. also expressed that they would get rid of the stale and bring forth the fresh to help the rubber chemicals products break away from the risk of “GHW/ GHF” as early as possible.
