环境科技
環境科技
배경과기
ENVIRONMENTAL SCIENCE AND TECHNOLOGY
2014年
2期
30-35
,共6页
平推流反应器%光催化%二氧化钛%乙酰甲胺磷
平推流反應器%光催化%二氧化鈦%乙酰甲胺燐
평추류반응기%광최화%이양화태%을선갑알린
Plug flow reactor%Photocatalysis%TiO2%Acephate
在平推流光化学反应器中采用纳米TiO2光催化乙酰甲胺磷溶液，考察了多种因素对矿化效果的影响。研究结果表明：随着催化剂浓度的增加，乙酰甲胺磷矿化率逐渐升高，当催化剂质量浓度在0.4 g/L时，其矿化率达到最大值为91.36%，然而当催化剂浓度继续增加时，由于TiO2的屏蔽效应，矿化效率反而降低；由于催化剂表面吸附位点的限制，乙酰甲胺磷矿化率随其初始浓度的增加而降低，乙酰甲胺磷光催化矿化过程符合准一级反应动力学模型以及Langmuir-Hinshelwood模型，其相关参数 k=1.05×10-5 mol/（L·min）和 K=7638 L/mol。随着反应液pH值的增大，乙酰甲胺磷矿化率也随之升高，其原因是在反应液pH值升高，溶液中OH-浓度增加，OH-可以充当光致空穴的俘获剂，加强氧化效果；在较低流速时，光催化矿化率随着流速的增加而升高，然而流速进一步增加时，矿化率反而下降。流速增加既能够增加乙酰甲胺磷与催化剂之间的碰撞，也能增加催化剂微粒的聚集。
在平推流光化學反應器中採用納米TiO2光催化乙酰甲胺燐溶液，攷察瞭多種因素對礦化效果的影響。研究結果錶明：隨著催化劑濃度的增加，乙酰甲胺燐礦化率逐漸升高，噹催化劑質量濃度在0.4 g/L時，其礦化率達到最大值為91.36%，然而噹催化劑濃度繼續增加時，由于TiO2的屏蔽效應，礦化效率反而降低；由于催化劑錶麵吸附位點的限製，乙酰甲胺燐礦化率隨其初始濃度的增加而降低，乙酰甲胺燐光催化礦化過程符閤準一級反應動力學模型以及Langmuir-Hinshelwood模型，其相關參數 k=1.05×10-5 mol/（L·min）和 K=7638 L/mol。隨著反應液pH值的增大，乙酰甲胺燐礦化率也隨之升高，其原因是在反應液pH值升高，溶液中OH-濃度增加，OH-可以充噹光緻空穴的俘穫劑，加彊氧化效果；在較低流速時，光催化礦化率隨著流速的增加而升高，然而流速進一步增加時，礦化率反而下降。流速增加既能夠增加乙酰甲胺燐與催化劑之間的踫撞，也能增加催化劑微粒的聚集。
재평추류광화학반응기중채용납미TiO2광최화을선갑알린용액，고찰료다충인소대광화효과적영향。연구결과표명：수착최화제농도적증가，을선갑알린광화솔축점승고，당최화제질량농도재0.4 g/L시，기광화솔체도최대치위91.36%，연이당최화제농도계속증가시，유우TiO2적병폐효응，광화효솔반이강저；유우최화제표면흡부위점적한제，을선갑알린광화솔수기초시농도적증가이강저，을선갑알린광최화광화과정부합준일급반응동역학모형이급Langmuir-Hinshelwood모형，기상관삼수 k=1.05×10-5 mol/（L·min）화 K=7638 L/mol。수착반응액pH치적증대，을선갑알린광화솔야수지승고，기원인시재반응액pH치승고，용액중OH-농도증가，OH-가이충당광치공혈적부획제，가강양화효과；재교저류속시，광최화광화솔수착류속적증가이승고，연이류속진일보증가시，광화솔반이하강。류속증가기능구증가을선갑알린여최화제지간적팽당，야능증가최화제미립적취집。
The nanosized TiO2 photocatalysis was used to mineralize acephate solution in a plug flow simulation reactor and the influence of the different factors on the mineralization efficiency were investigated. The results showed that the mineralization efficiency of acephate increases with elevated concentration of TiO 2 suspension. When the concentration of TiO2 was up to 0.4 g/L, the mineralization rate reached the maximum (91.36%). When the concentration of TiO 2 was above 0.4 g/L, the efficiency reduced slightly due to the shielding effect; the kinetic rate of acephate mineralization decreased with increasing initial concentration of acephate, which could be described using the first-order model. The Langmuir-Hinshelwood model was used to rationalize the mechanisms of reactions occurring on TiO 2 surfaces and the value of k and K of L-H model constants were: k=1.05 × 10-5 mol/(L·min) and K=7 638 L/mol;the OH-concentration increased with the pH, which was considered as a acceptor to trap, which could inhibit the recombination of photogenerated hole and charges, thereby improving the acephate photocatalytic mineralization efficiency; inorganic ions was considered as a acceptor to trap photogenerated electrons, which could inhibit the recombination of photogenerated hole and electrons, thereby improving the glyphosate photocatalytic mineralization efficiency.
