本文選題：電容去離子 + 高鹽廢水��； 參考：《武漢理工大學(xué)》2014年博士論文

【摘要】：在石煤提釩焙燒過程中通常需要添加一定量的工業(yè)鹽作為焙燒添加劑促進(jìn)釩的提取，因此，提釩過程會(huì)產(chǎn)生大量的高鹽度、高礦化度的廢水，目前處理這種高鹽廢水常用的方法有熱法和膜法，普遍存在能耗大、成本高等問題。為探索性能更為優(yōu)異的高鹽廢水處理方法，本研究采用電容去離子技術(shù)處理高鹽廢水，研究電極材料對(duì)脫鹽的影響，探討不同材料的吸附動(dòng)力學(xué)過程，并對(duì)比電極材料改性前后對(duì)石煤提釩廢水的處理性能。 通過比較不同活性炭電極的電容去離子脫鹽能力，結(jié)合活性炭化學(xué)、物理、電化學(xué)特性分析，得出吸附性能好的電極材料所具備的一般特性，指導(dǎo)電容去離子電極材料的選取。研究表明：在相同條件下進(jìn)行電容去離子脫鹽，礦物質(zhì)活性炭電極的吸附量約為木質(zhì)活性炭電極吸附量的4倍，是椰殼活性炭電極吸附量的7.5倍。導(dǎo)致吸附能力差異的主要原因是礦物質(zhì)活性炭雜質(zhì)含量少，孔隙結(jié)構(gòu)發(fā)達(dá)，含氧官能團(tuán)豐富，且電容量高、電阻較低，因而電容去離子電極材料的選取應(yīng)具有以上特性。 電容去離子操作的最佳工藝參數(shù)是：操作電壓為2.0V，流速為25mL/min，電極板間距為3mm時(shí)，礦物質(zhì)活性炭電極的粘結(jié)劑含量為9%。處理不同濃度NaCl溶液的動(dòng)力學(xué)研究表明，電容去離子吸附過程滿足準(zhǔn)一階動(dòng)力學(xué)吸附方程。 電容去離子過程離子選擇性吸附研究表明：離子濃度是影響電極吸附量的主要因素；當(dāng)離子濃度相同時(shí)，荷電量越高的離子，吸附量越大；相同荷電量的離子，水合半徑越小，吸附量越大。對(duì)不同單一電解質(zhì)溶液的電容去離子過程吸附動(dòng)力學(xué)研究表明：活性炭電極對(duì)不同離子的吸附速率大小順序?yàn)椋篎e3+Al3+ Ca2+ Mg2+ K+ Na+，說明電極對(duì)高價(jià)離子的吸附速度大于低價(jià)離子，相同價(jià)態(tài)的離子，水合半徑越小，吸附速率越快。利用3級(jí)電容去離子串聯(lián)處理石煤提釩高鹽廢水，操作電壓為2.0V，流量為25mL/min，電極板間距為3mm，處理時(shí)間為每級(jí)1h，活性炭電極對(duì)離子總吸附量達(dá)到了87.03mg/g。 為了進(jìn)一步提高電極材料的吸附能力，對(duì)其進(jìn)行表面改性，硝酸改性活性炭的吸附性能最好。動(dòng)力學(xué)研究表明，硝酸改性可以提高活性炭的吸附速率常數(shù)。硝酸改性提高活性炭的含氧官能團(tuán)含量，如羥基和羧基的含量，并產(chǎn)生了x新的官能團(tuán)C-N，降低了活性炭電極的疏水性，提高了電極與溶液的接觸面積，進(jìn)而增加了電極對(duì)離子的吸附量，同時(shí)提高了電極的電容量，降低電極的電阻。 考察硝酸改性對(duì)其他碳基電極材料的處理效果，對(duì)多壁碳納米管進(jìn)行改性，在相同的操作條件下，，改性多壁碳納米管電極的吸附量比未處理的多壁碳納米管高44.9%。說明硝酸改性方法不僅可以提高活性炭電極的性能，也適用于對(duì)多壁碳納米管電極的改性。 電容去離子處理石煤提釩廢水的電耗分析表明：將廢水含鹽量從30388mg/L降至1500mg/L以下，硝酸改性活性炭電極比未處理活性炭電極可以節(jié)約22.4%的電耗。同時(shí)降低了電極材料的用量，縮短了處理時(shí)間。
[Abstract]:In the process of roasting stone coal for vanadium extraction, a certain amount of industrial salt is needed to be used as a roasting additive to promote the extraction of vanadium. Therefore, the process of vanadium extraction will produce a large amount of high salinity and high salinity wastewater. At present, the common methods for treating this high salinity waste water are hot and membrane methods, which have high energy consumption and high cost. The treatment of high salt wastewater is more excellent. This study uses capacitance deionization technology to treat high salt waste water, studies the effect of electrode materials on desalination, discusses the adsorption kinetics of different materials, and compares the treatment performance of the vanadium extraction wastewater before and after the modification of the electrode materials.
By comparing the deionization deionization capacity of different activated carbon electrodes, combining with the chemical, physical, and electrochemical properties of activated carbon, the general characteristics of the electrode materials with good adsorption properties are obtained, and the selection of the capacitance deionized electrode materials is instructed. The adsorption capacity of the electrode is about 4 times that of the wood active carbon electrode and 7.5 times the adsorption capacity of the coconut active carbon electrode. The main reason for the difference of the adsorption capacity is that the content of the mineral activated carbon is less, the pore structure is developed, the oxygen functional group is rich, the capacitance is high, and the resistance is low, so the selection of the capacitance deionized electrode material should be set up. There are above characteristics.
The optimum process parameters for the deionized operation are: the operating voltage is 2.0V, the flow rate is 25mL/min, and the spacing of the electrode plate is 3mm. The kinetic study of the content of the binder content of the mineral activated carbon electrode is 9%. for the treatment of different concentration NaCl solutions. The kinetic study shows that the process of capacitive deionized adsorption meets the first order kinetic adsorption equation.
The study of ion selective adsorption in the process of capacitive deionization shows that the concentration of ion is the main factor affecting the adsorption capacity of the electrode; when the ion concentration is the same, the higher the charged ion, the larger the adsorption capacity; the smaller the hydration radius, the larger the adsorption capacity. The kinetic study shows that the adsorption rate of activated carbon electrodes on different ions is: Fe3+Al3+ Ca2+ Mg2+ K+ Na+, indicating that the adsorption rate of high valence ions is greater than that of low valence ions, the same valence ions, the smaller the hydration radius, the faster the adsorption rate, the 3 stage electric capacitive deionization is used to process the high salt waste water from the stone coal to extract vanadium. The total adsorption capacity of the activated carbon electrode was 87.03mg/g., with a voltage of 2.0V, a flow rate of 25mL/min, an electrode plate spacing of 3mm, and a treatment time of 1H.
In order to further improve the adsorption capacity of electrode materials and surface modification, the adsorption performance of nitric acid modified activated carbon is the best. Kinetic study shows that nitric acid modification can improve the adsorption rate constant of activated carbon. Nitric acid modification improves the content of oxygen containing functional groups, such as hydroxyl and carboxyl groups, and produces a new x function. The group C-N reduces the hydrophobicity of the activated carbon electrode, increases the contact area between the electrode and the solution, and then increases the adsorption amount of the electrode to the ion, at the same time, the capacitance of the electrode is increased and the resistance of the electrode is reduced.
The treatment effect of nitric acid modification on other carbon based electrode materials was investigated. Under the same operating conditions, the adsorption capacity of the modified multi wall carbon nanotube electrode was higher than that of the untreated multi walled carbon nanotubes (44.9%.). The modified method not only improved the performance of the activated carbon electrode, but also applied to the multi wall carbon. Modification of nanotube electrodes.
The electricity consumption analysis of the removal of vanadium wastewater from the stone coal with capacitive deionization shows that the salt content of the wastewater is reduced to less than 1500mg/L from 30388mg/L, and the nitric acid modified activated carbon electrode can save 22.4% of the electricity consumption than that of the untreated activated carbon electrode. At the same time, the amount of electrode material is reduced and the treatment time is shortened.

【學(xué)位授予單位】：武漢理工大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2014
【分類號(hào)】：TQ150.1;X703

【參考文獻(xiàn)】

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