International leader in ionic liquid separation and recovery of ammonia-containing gas technology

On May 10, the China Petroleum and Chemical Industry Federation organized and held the scientific and technological achievement appraisal meeting on the "Green New Technology of Ammonia Absorption and Recycling for Industrial Use by Ionic Liquid Method" in an online + offline manner
.
The appraisal committee headed by He Mingyuan, an academician of the Chinese Academy of Sciences, believes that the technology is highly innovative, advanced, mature and reliable, with independent intellectual property rights, and is at an international leading level; it has outstanding economic and environmental benefits, and is in line with the national energy conservation and environmental protection industry policy.
The industrial ammonia-containing gas treatment and recycling in the industry has broad application prospects
.

The achievement was jointly completed by the Institute of Process Engineering of the Chinese Academy of Sciences, the Chemical Branch of Jinduicheng Molybdenum Industry Co.
, Ltd.
and other units
.
Academician Zhang Suojiang, director of the Institute of Process Research, Chinese Academy of Sciences, told reporters that ionic liquids, as a new type of medium composed of anions and cations, have the characteristics of designable structure, hydrogen bond-electrostatic coupling, and adjustable acidity and alkalinity, which make them more effective for ammonia molecules.
High solubility and absorption selectivity
.
The ionic liquid itself also has extremely high cohesive energy, extremely low vapor pressure, and is non-volatile.
It will not cause secondary pollution due to its volatilization like organic solvents during desorption and regeneration
.
Therefore, ionic liquids have inherent advantages in the absorption and separation of gases
.

"Based on this, we innovatively proposed a new green technology for the purification and recovery of ammonia-containing gas in non-aqueous ionic liquid systems, and invented a functional composite ionic liquid absorbent with high ammonia absorption and good cycle stability, breaking through the absorption of ionic liquid due to its high viscosity.
Low speed and high cost restrict large-scale industrial applications,
" Zhang Suojiang said
.
Based on the characteristics of ionic liquids, a packed tower with enhanced absorption of internal components and an efficient and rapid desorption equipment for ionic liquid membranes were designed and developed; a new process of ionic liquid absorption, purification and regeneration was developed to realize continuous online purification without stopping, forming an industrial ionic liquid method.
A complete set of new technologies for separation and recycling of ammonia-containing gas
.
Compared with the water washing process of the imported device, the new technology has the advantages of low energy consumption, direct recovery of ammonia, discharge of exhaust gas up to the standard, and production of ammonia-free wastewater
.

After joint research, the technology has been successfully applied in Jinmo Chemical Branch in Weinan, Shaanxi Province, and the world's first industrial demonstration plant for the recovery of ammonia from molybdenum chemical exhaust gas with a processing capacity of 130 million Nm³/year has been built
.
The device has been running continuously and stably for 40 months since January 2019, and the comprehensive cost has been reduced by more than 36% compared with the existing water washing method, and the recycling of ammonia resources has been realized
.
Through online monitoring by the environmental protection department, the emission of ammonia-containing tail gas reaches the standard, which solves the environmental protection problems faced by the enterprise in the production process, and provides a model for the large-scale application of ionic liquids in the field of industrial gas separation
.

It is reported that ammonia, as one of the important basic chemical products, is widely used in chemical, metallurgy, pharmaceutical, electronics and other industries.
For example, in the production process of synthetic ammonia, urea, ammonium molybdate, molybdenum oxide, melamine, etc.
gas
.
At the same time, ammonia is an alkaline gaseous pollutant, and the secondary particles of PM2.
5 such as ammonium sulfate and ammonium nitrate generated by the reaction with SOX and NOX in the atmosphere are one of the important reasons for the formation of smog
.
The national "Thirteenth Five-Year Plan" for Ecological Environmental Protection has specifically increased the restriction on the total emission of ammonia nitrogen pollutants, and the ammonia emission standard has become more and more stringent
.

Although the existing water washing method, sulfuric acid or phosphoric acid aqueous solution absorption method can realize the purification and discharge of ammonia-containing tail gas, but the obtained dilute ammonia water, sulfuric acid or ammonium phosphate has low utilization value and is easy to cause secondary pollution, which has always plagued the green development of the industry.
major problem
.
It is urgent to develop transformative technologies for efficient and low-energy consumption purification and separation and recovery of ammonia-containing exhaust gas, and it is also an urgent expectation for the green upgrade of the industry
.

At present, the total amount of ammonia-containing exhaust gas in China's industry is relatively large, about 3 million tons per year, involving many industries, and the potential for recycling is huge
.
Efficient separation and recovery of ammonia in industrial ammonia-containing gas is the main way to effectively control ammonia pollution and reduce the formation of secondary particulate matter in haze
.
At the same time, the comprehensive recovery and utilization of ammonia resources not only has significant economic benefits, but also reduces the demand for synthetic ammonia, thereby indirectly reducing carbon emissions
.
This technology provides an advanced and reliable solution for the purification and recycling of industrial ammonia-containing gas, which will greatly promote the industrialization of ionic liquids and enhance China's influence in the world of ionic liquids and green chemistry
.