理起驗(yàn)∥等分PTCA(PART B: CHEM. ANAL.20084442↓工作報(bào)污水色度的測定姚國,王建衛(wèi)(東莞市市區(qū)污水處理廠,東莞523080)摘要:作為對(duì)常規(guī)方法的改進(jìn),提出用分光光度法代替目視比色法作為污水色度的測試方法,并釆用重鉻酸鉀及硫酸鈷配制的稀硫酸溶液(酸度約0.02mol·Lˉ1)作為測定色度的標(biāo)準(zhǔn)溶液以此標(biāo)準(zhǔn)溶液的吸收峰350mm作為測定波長測定標(biāo)準(zhǔn)及水樣的吸光度。制作了色度在10°~100之間的標(biāo)準(zhǔn)曲線,對(duì)試液的溫度、濁度及酸度的影響作了試驗(yàn),此方法的檢出限為色度5°,關(guān)鍵詞:分光光度法;目視比色法;色度;污水中圖分類號(hào):0657.31文獻(xiàn)標(biāo)識(shí)碼:A文章編號(hào):1001-4020(2008)010061402Determination of Colority of Sewage WaterYAO Guo, WaNG Jianwei(Dongguan Muicipal Sewage Treatment Plant, Dongguan 523080, China)Abstract: As a modification for the conventional method determination of colority of sewage water wasimproved by using spectrophotometry instead of the visual colorimetry, and using a dil. H2 SO. solution(ca.0.02 molL-I)of K, Cr O, and CoSO as standard solution for preparation of standard cuve. Measurement ofabsorbance was made at the wavelength of 350 nm, which is the absorption maxima of the standard solution. Alinear standard curve covering colority between 10"to 100 was prepared. Factors influential to the determination(ie temperature, turbidity and acidity of the water sample) were studied Detection limit of this method was foundtobe5°Keywords: Spectrophotometry: Visual colorimetry: Colority: Sewage water色度是城鎮(zhèn)污水處理廠水質(zhì)監(jiān)測的一項(xiàng)基本控用眼睛分辨。標(biāo)準(zhǔn)比色法通過配制一系列色度標(biāo)準(zhǔn)制項(xiàng)目。水中色度的測定方法有兩種,測定較清潔溶液然后與水樣進(jìn)行目視比色,最后確定出水樣的的天然水和飲用水的色度用鉑鉆標(biāo)準(zhǔn)比色法或鉻鈷色度。這兩種方法的共同缺點(diǎn)是受比色管顏色、刻標(biāo)準(zhǔn)比色法,測定工業(yè)污水和受工業(yè)污水污染的度天氣和人為影響因素大。試驗(yàn)結(jié)果發(fā)現(xiàn)鉻鈷標(biāo)地表水及生活污水用稀釋倍數(shù)法。新鮮的生活污水準(zhǔn)溶液在350mm波長附近有最大吸收峰,且在10中含大量的有機(jī)物、無機(jī)鹽、懸浮物和膠態(tài)物質(zhì)使~100°色度范圍內(nèi)吸光度與色度符合朗伯比耳定水體混濁,呈淺灰褐色。生活污水經(jīng)污水處理廠處律本法改用重鉻酸鉀代替氯鉑酸鉀配制色度標(biāo)準(zhǔn)理后或用0.45pm濾膜過濾后水樣較清色度很溶液,用分光光度計(jì)代替人眼進(jìn)行定量測定低微黃色,可以采用上述兩種方法測定。1試驗(yàn)部分稀釋倍數(shù)法需將水樣稀釋成不同的稀釋倍數(shù)然后與光學(xué)純水比較最后確定出水樣的稀釋倍數(shù),1.1儀器與試劑對(duì)未受工業(yè)廢水污染的生活污水及污水處理廠處理Carry50紫外可見分光光度計(jì); Millipore純水后的出水在稀釋5~20倍之間色度差異不大,很難機(jī),濾膜及抽濾裝置500°鉻鉆標(biāo)準(zhǔn)溶液:準(zhǔn)確稱取重鉻酸鉀收稿日期:200606-130.0437g及硫酸鈷(CoSO4·7H2O)1.000g溶于作者簡介:姚國(95-),女,廣州市人,工程師,主要從事化少量水中,加入濃硫酸0.5mL,用水稀釋至學(xué)分析工作500mL此溶液的色度為500°姚國等污水色度的測定1.2標(biāo)準(zhǔn)曲線的繪制收峰掃描圖譜見圖3。分別取500°鉻鉆標(biāo)準(zhǔn)溶液0,1,2,…,10mL于0mL比色管中,用純化水稀至刻度,搖勻,各管的色度分別為10°,20°,40°,60°,80°,100°,于350m波長處,以純水為空白,以1cm石英比色皿測定吸光度繪制標(biāo)準(zhǔn)曲線,相關(guān)系數(shù)為0.999,見圖1。當(dāng)01圖3色度為10°(a),20°(b),40°(c),60°(d),80°(e)及100(D的鉻(Ⅵ)鈷(Ⅱ)標(biāo)準(zhǔn)溶液的吸收光譜Fig. 3 Absorption spectra of Chromium( V)-Cobalt(I)tandard solutions corresponding to colority of 10(a)色度(")20°(b),40°(c),60°(d),80°(e)andl00°(D圖1用鉻(Ⅵ)鈷(Ⅱ)標(biāo)準(zhǔn)溶液(色度范圍10°~100°)制作的色度標(biāo)準(zhǔn)曲線(3)分別取污水處理廠的生活污水的原進(jìn)水和Fg1 Standard curve of colority( in the range of1o-100)處理后的出水,以相同的操作步驟在200~800nmprepared with Cr(Ⅵ)Co(Ⅱ) standard solution波長范圍內(nèi)掃描;在257mm處的紫外區(qū),由于水樣500°鉑鈷標(biāo)準(zhǔn)溶液與鉻鉆標(biāo)準(zhǔn)溶液顏色一致,中含有機(jī)物和硝酸鹽干擾色度的測定選取用靠近均呈黃色。稀釋后同一色度的標(biāo)準(zhǔn)溶液顏色也一可見光區(qū)且無干擾的350mm作為測定波長,并制致可用鉻鈷標(biāo)準(zhǔn)溶液代替鉑鈷標(biāo)準(zhǔn)溶液進(jìn)行測定。作色度在10°~100°之間的標(biāo)準(zhǔn)曲線。掃描圖譜見2結(jié)果與討論圖4。2.1測定波長的選擇(1)分別取10°~100°鉑鈷標(biāo)準(zhǔn)溶液,以純化水為空白進(jìn)行基線效正,用1cm石英比色皿在200~800nm波長范圍內(nèi)掃描,在262nm波長處有最大吸收峰,且吸光度大于1,小于300mm波長處幾乎無吸收,故鉑鈷標(biāo)準(zhǔn)溶液在10°~100°范圍內(nèi)不適合波長λ/mm用于定量測定。掃描圖譜見圖2。圖4進(jìn)水及出水樣的吸收光譜Fig. 4 Absorption spectra of water samples at inlet and outlet2.2溫度、濁度(、酸度(的影響常溫下溫度對(duì)色度的影響很小,可以忽略。濁度對(duì)色度的影響較大可將水樣經(jīng)0.45μm濾膜過濾后除去。在微酸性和中性條件下,酸度對(duì)色度的影響較小,可以忽略。2.3檢出限圖2色度為10°的鉑鉆標(biāo)準(zhǔn)溶液的吸收光譜分光光度法中以扣除空白值后的與0.01吸光Fig. 2 Absorption spectrum of platinum Cobalt standard度相對(duì)應(yīng)的濃度為檢出限。本法檢出限為色度5°2.4水樣的測定含懸浮物、混濁的水樣需經(jīng)045m濾膜過濾(2)分別取10~100鉻鈷標(biāo)準(zhǔn)溶液,以相同的后進(jìn)行測定。分取預(yù)處理過的水樣50mL于比色操作步驟在200~800mm波長范圍內(nèi)掃描,鉻鈷標(biāo)管中(或進(jìn)行適當(dāng)稀釋)按繪制標(biāo)準(zhǔn)曲線的步驟測準(zhǔn)溶液有兩個(gè)最大吸收峰第一個(gè)在257mm附近,定吸光度,根據(jù)標(biāo)準(zhǔn)曲線儀器自動(dòng)算出水樣的色度第二個(gè)在350mm附近,為重鉻酸鉀的兩個(gè)特征吸(下轉(zhuǎn)第65頁)62王永祥等:大別山區(qū)野生黎豆中微量元素的測定與品質(zhì)評(píng)價(jià)表2回收率和精密度試驗(yàn)及與 ICP-AES法他兩種同類作物,有較高的開發(fā)利用價(jià)值。測定結(jié)果的比較(n=8)Tab. 2 Tests for recovery and precision, and analyt.參考文獻(xiàn)ults obtained by this method and by ICP-AES[1]劉萍,吳世德原子吸收光譜法測竹香米和大米中銅測得量加標(biāo)量測得總量ICP-AES法鋅錳鈉鎂含量[].中國公共衛(wèi)生雜志,2002,23(3)元素 Amt Am' t of Total am't測定值of the stds回收率of the Recovery /RSD Results528528element added element[2]李雯,杜秀月原子吸收光譜法及其應(yīng)用[]鹽湖研foundfoundby ICP-AES究雜志,2003,11(4):67-71.e/(mg.L-)p(mg·L-1)[3]燕冰楊軍周靖火焰原子吸收光譜法測定冬葵葉Mg0.180.200.40110.00.170.19中幾種營養(yǎng)元素含量[]哈爾濱師范大學(xué):自然科學(xué)Ca0.350.400.7292.51.140.37學(xué)報(bào),2003,19(4):77-80Zn0.410.400.8097.50.480.38[4]王秀敏原子吸收光譜法測定小麥品種子粒中鉀鈉鈣0.330.300.65106.71.340.29鎂的含量[].河北農(nóng)業(yè)大學(xué)學(xué)報(bào),203,26(4):9093Fe5.255.0010.495.81.865.10[5]王平孫慧張?zhí)m杰黑米黑豆、黑芝麻中幾種微量元Mn0.460.500.959802.170.44素含量的測定[]鞍山師范學(xué)院學(xué)報(bào),200,2(1):9表3黎豆與黃豆、黑豆中6種微量元素含量的比較[6] Umemura T, Kitaguchi R, Haraguchi H. CounterionTab. 3 Comparison of the content of the 6 trace-elements inic Detection by ICP-AES for Determination of inorga-Chineseand black beanic Anions in Water Elution Ion Chromatography Using6種痕量元素的測定值a Zwitterionic Stationary PhaseJ]. Anal Chem, 1998Content of the 6 trace-elements found70(5):936942[7 Doner G, Ege A. Evaluation of digestion proceduresMg Cafor the determination of iron and zinc in biscuits by黎豆2532177767.0920.86112.9041.02flame atomic absorption spectrometry[j]. Anal Chim黃豆2270204770.4615.14117.542437Acta,2004,520(1/2):217222ME 2098 2 124 66.72 18.85 139. 74 25. 80[8] Balasubramanian S, Pugalenthi V. Determination ofter by鎂、鐵等元素,從黎豆與黑豆、黃豆的測定結(jié)果比較coupled plasma atomic emission spectrometry [J].中可以看出,黎豆中鎂、錳、銅的含量均明顯高于其Talanta,1999,50(3):457-467(上接第62頁)分取污水處理廠的生活污水的原進(jìn)水和處理后由表1可知,鉻鉆標(biāo)準(zhǔn)比色法得到的結(jié)果是某的出水,經(jīng)預(yù)處理后,按文獻(xiàn)[1]中的標(biāo)準(zhǔn)比色法和一范圍,本方法得到結(jié)果是一個(gè)確定的值,兩種方法本方法進(jìn)行測定,結(jié)果見表1。得到結(jié)果一致。本方法的優(yōu)點(diǎn):預(yù)先建好標(biāo)準(zhǔn)曲線,表1用目視比色法與分光光度法測得的色度結(jié)果的比較每次測定時(shí)只需將水樣進(jìn)行預(yù)處理然后測定吸光Tah1 Comparison of colority determined by visual colorimetry度,儀器自動(dòng)算出水樣的色度。操作簡單,結(jié)果準(zhǔn)and spectrophotometry確,減少了人為誤差。測得色度值values of colority found degree參考文獻(xiàn)測定方法Method of 2005040320050507[1]國家環(huán)保局《水和廢水監(jiān)測分析方法》編委會(huì)水和廢水監(jiān)測分析方法[M]4版北京:中國環(huán)境出版社2002[2]GB11903-1989水質(zhì)色度的測定[S]目視比色法15°~210左右10°15°5°~10°分光光度法18.9°10.8°8.4°