用于水中色氨酸去除的活性炭材料优选实验研究

Experimental study on optimization of activated carbon materials for removal of tryptophan in water

为了对净水厂消毒副产物进行减量化处理,选取碘值不同的椰壳活性炭、柱状活性炭等5种材料去除前驱物色氨酸。研究了不同条件下5种活性炭材料对色氨酸去除效果的影响。结果表明,当改变p H时,去除效果较好的是柱状碘值800的活性炭,且大多数活性炭在pH 4左右去除效果最好;活性炭的使用寿命和运行周期影响去除效果,柱状类活性炭和椰壳碘值800活性炭在16 h内性能出现下降趋势,而其他椰壳活性炭没有明显下降;柱状类和椰壳碘值800活性炭在7 h左右去除效果稍好。随着色氨酸浓度增加,柱状类活性炭去除效果最好,柱状碘值1000活性炭对低浓度色氨酸(1~2 mg/L)去除效果更好,柱状碘值800活性炭对稍高浓度色氨酸(2~5 mg/L)去除效果更好。总体而言,柱状碘值800活性炭对色氨酸等微量有机物去除效果较好,为色氨酸等消毒副产物前驱物去除的研究提供了参考依据。

In order to reduce disinfection by-products in water purification plants,five kinds of activated carbon materials with different iodine values,including coconut shell-derived and columnar materials,are selected to treat with the precursor tryptophan.Effects of different activated carbon materials on the removal of tryptophan under different conditions are studied.Results show that columnar activated carbon with an iodine value of 800 exhibits the best removal effect when p H value changes.Most activated carbon materials show their best removal effect at p H=4.The service life and operation cycle of activated carbon can affect the removal effect.Coconut shell-derived activated carbon with an iodine value of 800 and two kinds of columnar activated carbon show a downward trend during the 16-hour adsorption time,while the other two coconut shell-derived ones do not show a significant decline.Coconut shell-derived activated carbon with an iodine value of 800 and two kinds of columnar activated carbon present better removal effect in about 7 hours.With the increase of tryptophan concentration,columnar activated carbon materials give better removal effect.Columnar activated carbon with an iodine value of 1,000 exhibits a better removal effect to low concentration tryptophan(1-2 mg·L^(-1))while that with an iodine value of 800 shows better removal effect to slightly higher concentration(2-5 mg·L^(-1)).In a sum,columnar activated carbon with an iodine value of 800 has the best removal effect on trace organic matters such as tryptophan,which provides a certain reference for the application research on the removal of tryptophan and other disinfection by-product precursors.