Background and structural properties of adsorption resin
Adsorption resin is a resin adsorbent
, which is developed on the basis of ion exchange resin. In the 1970s, with the development of macroporous ion exchange resins, macroporous adsorption resins came into being. Adsorption resin is a kind of highly crosslinked body-type polymer beads without ion exchange groups. It has many molecular-level pores inside, which provide diffusion channels and adsorption sites. In particular, the advent of new resins has made them extremely valuable applications in pesticides, medicines, chemicals and wastewater treatment.
Compared with the previous adsorbents (activated carbon, molecular sieve, alumina, etc.), the performance of the adsorption resin is very outstanding, mainly due to the large amount of adsorption, easy to elute, a certain selectivity, good strength, and can be reused. In particular, the structure of the resin can be designed for different applications, so that the adsorption resin has become a multi-variety series, which shows excellent adsorption separation performance in many important fields.
The excellent performance of adsorption resin
makes it an irreplaceable separation material in the treatment of organic sewage. Phenol wastewater, pesticide wastewater, and dye wastewater are several types of organic wastewater that are difficult to treat. Adsorption of these pollutants in wastewater by resin method can not only eliminate pollution, but also realize resource recycling through elution. http://euhowblog.com
Application of adsorption resin in industrial wastewater treatment
Resin adsorption method for treatment of sulfazone production wastewater
Sulfadiazine production wastewater is generally black-red, with pH ≥11, COD above 13000mg / L, sulfonamide content of 17-22g / L, NaNO3 content of 230g / L, Na2CO3 of 60g / L, and NaOH and unknown reaction products. Small amount of organics.
Xu Yueqing and others took sulfazone production wastewater from a chemical plant in Jiangxi as an example. Aiming at the production characteristics of this wastewater, they studied the process of treating sulfazone production wastewater with macroporous adsorption resin and its optimal process conditions, and the economic benefits of wastewater treatment. It was evaluated.
The results of several tests showed that the optimal treatment capacity of the wastewater by the resin was 13 times the volume of the resin. The working adsorption capacity of the resin was 191 g / L. The cumulative adsorption rate of the sulfonamide was 88122%. The desorption was performed with a 5% NaOH solution. It takes about 3 times the resin volume of the desorbent to achieve complete desorption, with a desorption rate of 97156% and a sulfonamide recovery rate of about 86%.
Using the macroporous resin adsorption method to treat sulfazone production wastewater can effectively recover sulfa and sodium nitrate, and bring objective economic benefits. According to the survey of the plant, every metric ton of sulfazone production produces 315m3 of wastewater, which is calculated as 1m3 of wastewater as follows: This study The recovery rate of sulfonamide is 86%. It is expected that the recovery rate of sulfonamide will not be lower than 90% in large-scale production. The following analysis is based on the sulfonamide recovery rate of 80% and NaNO3 recovery rate of 95%. Recovering 1,318 kg of sulfonamide (SN) and NaNO 321,815 kg, and can greatly reduce the environmental pollution of the substances contained in the wastewater. The wastewater treated by the above process is monitored by the Environmental Monitoring Center of Shijiazhuang City, according to the "Integrated Wastewater Discharge Standard" (GB897821996), The COD removal rate in the wastewater reaches 86%, the total salt content is reduced by 95%, and the environmental benefits are significant.
The treatment process technology is feasible, simple operation, low operating cost, significant environmental and economic benefits, stable treatment effect, and is suitable for promotion.http :
Treatment of methyl salicylate production wastewater by resin adsorption method
Methyl salicylate, also known as holly oil, exists widely in nature and is the main component of calla and xiaodang oil. It is also found in essential oils of tuberose, lime tree, ylang ylang, clove tea, etc. It is a versatile perfume, solvent and fine chemical intermediate. It is mainly obtained from salicylic acid and methanol as raw materials under the catalysis of concentrated sulfuric acid. At present, most manufacturers in China use batch reaction processes, which need to be carried out under conditions of high alkyd ratio and high sulfuric acid dosage. In addition to the target product methyl salicylate, a small amount of by-product 5-sulfosalicylic acid is also produced and produced. A large amount of high-concentration organic wastewater, which has not been effectively treated so far, has caused serious environmental pollution. The resin adsorption method has been successfully used to treat a variety of high-concentration chemical wastewater. Therefore, Cheng Xiumei, Chen Jinlong, etc. used resin adsorption to treat methyl salicylate production wastewater from a plant. After the wastewater was pretreated to remove methanol, a large amount of 5-sulfosalicylic acid and salicylic acid were removed by resin adsorption. Among them, 5-sulfosalicylic acid is an important pharmaceutical intermediate, which can be used in the manufacture of surfactants, dyes, organic catalysts, and indicators that can be used as a variety of metals, and has great recycling value. The experiment was screened to select the NDA-99 resin to treat the wastewater.
The experimental results show that the NDA-99 resin has stable adsorption-desorption performance and can remove most organic pollutants. The CODcr removal rate of the upper column liquid is close to 60%, and the desorption rate is close to 100%. In addition, the resin has no breakage during use and has good mechanical strength. After the wastewater sample was treated with resin adsorption, the effluent was colorless and transparent, and the CODcr decreased from 57000 to 59000 to about 6300 (mg / L).
Resin adsorption method for treatment of waste water from tartaric acid production
Tobias2acid (2-naphthylamine-1-sulfonic acid) is an important precursor for the synthesis of a variety of naphthalene derivatives such as azo dyes, naphthol, J acid, and γ acid. Β-naphthol is usually used as a raw material. It is prepared by sulfonylation, alkali neutralization and amination under low temperature conditions, and finally by acid hydrolysis reaction. Deep red acidic toxic waste water containing toluic acid and its precursors is produced during the production process, causing serious and long-term water environmental pollution
Xiao Fang et al. Used XDX-1 macroporous adsorption resin for dynamic adsorption treatment of waste water from Tobias acid production, and studied various factors affecting adsorption. The results show that the resin has a good adsorption capacity for tartaric acid and its precursors with a concentration of 14000 mg / L in wastewater. After tandem secondary adsorption, the concentration of tartaric acid and its precursors is reduced by 98% and the COD is reduced by 86%. %; Desorption with alkaline methanol solvent, the desorption efficiency reaches 98%, the tossic acid and its precursor recovered by the rectification desorption liquid can be returned to the production workshop, and the treated wastewater can reach the discharge standard after biochemical treatment.