Process for treatment of PTA refining wastewater through high-selectivity adsorbent

Abstract

The invention discloses a process for treatment of PTA refining wastewater through a high-selectivity adsorbent. The process comprises the following steps: extracting, selectively adsorbing p-xylene through the high-selectivity adsorbent, carrying out ultrafiltration and reverse osmosis and carrying out metal adsorption. The high-selectivity adsorbent is prepared through the following specific steps: uniformly mixing a silicon source, an aluminium source, a template agent and water according to a ratio, stirring for dissolving, transferring the mixture to a stainless steel crystallization kettle with a polytetrafluoroethylene liner, heating for crystallization, filtering, washing, drying and roasting so as to obtain an initial molecular sieve with good degree of crystallinity; deeply processing the initial molecular sieve, and forming to prepare into a strip-shaped high-selectivity molecular sieve. According to the process provided by the invention, the high-selectivity adsorbent is adopted to adsorb p-xylene in wastewater, the adsorption selectivity coefficient of p-xylene to cobalt ions can reach 7890 maximally, the adsorption selectivity coefficient of p-xylene to manganese ions can reach 9578 maximally and the adsorption capacity of p-xylene can reach 40 mg/g or above, so that erosion of p-xylene to a reverse osmosis membrance can be effectively avoided.

Description

technical field [0001] The invention relates to the field of water treatment, in particular to a process for treating PTA refined wastewater with a highly selective adsorbent. Background technique [0002] Molecular sieves are made of (Si, Al)O 4 The skeleton structure composed of tetrahedrons is full of cavities and channels in its space grid structure, which has a large openness and a huge internal surface area (400-800m 2 / g), and the balance cations on the zeolite framework are not tightly combined with the framework, and it is very easy to exchange with the cations in the aqueous solution, so it has good adsorption and exchange performance. When the main pore diameter is larger than or substantially the same as that of p-xylene, and the silicon-alumina ratio is so high that it contains less metal ions or contains H with stronger adsorption capacity + Or metal ions, when the exchange effect with the metal ions in the solution is weak, this makes it possible to sele...

AI Technical Summary

Problems solved by technology

PTA refined wastewater contains organic pollutants and heavy metal ions at the same time. In the traditional "extraction-ultrafiltration reverse osmosis-adsorption" process, after the organic matter is recovered in the extraction process, the extractant PX will remain in the wastewater and erode the ultrafiltration reverse osmosis membrane. effect, causing the process to fail to operate stably and effectively for a long time

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