國內外學者在表面活性劑對多(duo)環(huan)芳烴污(wu)染(ran)土壤修復方面(mian)(mian)(mian)已經(jing)進行了不少有(you)意義的(de)研究和探索。但是已有(you)的(de)研究主要(yao)集中在傳統表面(mian)(mian)(mian)活(huo)性(xing)(xing)劑(ji)(ji),而傳統表面(mian)(mian)(mian)活(huo)性(xing)(xing)劑(ji)(ji)往往具有(you)毒性(xing)(xing)、二次污(wu)染(ran)、價(jia)格高等問題,因此尋找經(jing)濟、有(you)效、環(huan)保(bao)的(de)新型(xing)表面(mian)(mian)(mian)活(huo)性(xing)(xing)劑(ji)(ji)將成為(wei)未(wei)來應用(yong)表面(mian)(mian)(mian)活(huo)性(xing)(xing)劑(ji)(ji)修復多(duo)環(huan)芳烴污(wu)染(ran)土壤的(de)研究熱點及重點。
新型雙子(zi)表(biao)(biao)面(mian)活(huo)(huo)性(xing)(xing)劑(ji)與生物表(biao)(biao)面(mian)活(huo)(huo)性(xing)(xing)劑(ji)因其高效性(xing)(xing)、環境友好性(xing)(xing)等特點被廣泛關注,雙子(zi)表(biao)(biao)面(mian)活(huo)(huo)性(xing)(xing)劑(ji)和生物表(biao)(biao)面(mian)活(huo)(huo)性(xing)(xing)劑(ji)對有(you)機(ji)物的(de)增溶效率比傳統表(biao)(biao)面(mian)活(huo)(huo)性(xing)(xing)劑(ji)高。
離子表面活性劑的加入使非離子表面活性劑的濁點升高。在外加表面活性劑濃度一定時,非離子表面活性劑濃度越低,二者形成的混合物的電荷密度越高,膠束間的排斥力越大,從而濁點越高。在相同的非離子表面活性劑濃度下,外加離子表面活性劑濃度升高時,一般濁點也升高。這也是由于膠束表面電荷密度增大的緣故。因此,非離子表面活性劑與離子表面活性劑形成混合膠束的電荷密度的大小決定了濁點的高低。電荷密度越大,濁點越高。
醇(chun)(chun)(chun)、有機酸等助(zhu)表(biao)面活性(xing)(xing)劑(ji)(ji)對濁點(dian)(dian)(dian)(dian)的(de)(de)影響也(ye)是兩(liang)個(ge)因素共同(tong)作(zuo)用(yong)的(de)(de)結果(guo)。醇(chun)(chun)(chun)的(de)(de)親(qin)水(shui)基(ji)(ji)可與水(shui)形成氫(qing)鍵(jian)(jian),限制表(biao)面活性(xing)(xing)劑(ji)(ji)的(de)(de)膠(jiao)團化作(zuo)用(yong),使(shi)(shi)濁點(dian)(dian)(dian)(dian)升高;同(tong)時(shi)醇(chun)(chun)(chun)在膠(jiao)束(shu)(shu)的(de)(de)界(jie)面層和柵(zha)欄(lan)(lan)(lan)層中(zhong)增溶(rong)(rong),與水(shui)形成氫(qing)鍵(jian)(jian),膠(jiao)束(shu)(shu)總(zong)含水(shui)量增加,也(ye)使(shi)(shi)濁點(dian)(dian)(dian)(dian)升高。醇(chun)(chun)(chun)增溶(rong)(rong)在柵(zha)欄(lan)(lan)(lan)層中(zhong),親(qin)水(shui)基(ji)(ji)靠近表(biao)面活性(xing)(xing)劑(ji)(ji)的(de)(de)極(ji)性(xing)(xing)頭,空間(jian)阻礙及與醚形成氫(qing)鍵(jian)(jian)的(de)(de)作(zuo)用(yong)降低了表(biao)面活性(xing)(xing)劑(ji)(ji)的(de)(de)水(shui)合能(neng)力,使(shi)(shi)濁點(dian)(dian)(dian)(dian)下降。甲醇(chun)(chun)(chun)、乙(yi)醇(chun)(chun)(chun)碳(tan)鏈短,親(qin)水(shui)性(xing)(xing)強,在膠(jiao)束(shu)(shu)溶(rong)(rong)液中(zhong)大部分溶(rong)(rong)于水(shui),部分吸附于膠(jiao)束(shu)(shu)界(jie)面及柵(zha)欄(lan)(lan)(lan)層,從而使(shi)(shi)濁點(dian)(dian)(dian)(dian)升高;對碳(tan)數大于4的(de)(de)醇(chun)(chun)(chun),親(qin)水(shui)性(xing)(xing)差,多(duo)數增溶(rong)(rong)在柵(zha)欄(lan)(lan)(lan)層中(zhong),使(shi)(shi)濁點(dian)(dian)(dian)(dian)降低。對于多(duo)元(yuan)醇(chun)(chun)(chun),如乙(yi)二(er)醇(chun)(chun)(chun)、丙三醇(chun)(chun)(chun)、葡萄(tao)糖(tang)等,它們的(de)(de)羥基(ji)(ji)越多(duo),越易與表(biao)面活性(xing)(xing)劑(ji)(ji)醚鍵(jian)(jian)形成氫(qing)鍵(jian)(jian),使(shi)(shi)其水(shui)合作(zuo)用(yong)下降,濁點(dian)(dian)(dian)(dian)下降。