| 24小時熱門版塊排行榜 |
| 查看: 2273 | 回復: 19 | |||
cc0918zj鐵蟲 (初入文壇)
|
[求助]
求助怎么在化學沉淀反應(yīng)中控制溶液PH恒定在9,謝謝 已有6人參與
|
||
|
具體反應(yīng)是乙酸鈣溶液中滴加磷酸(85%wt),怎么控制整個反應(yīng)過程溶液PH恒定在9?文獻中是加氫氧化鈉溶液。 文獻原文 The starting materials used in this investigation are analytical-grade (CH3COO)2Ca·xH2O (99%, Aldrich Chemical company, Inc., USA) which is used as the Ca source, and H3PO4 (85%, Riedel-deHaen, Seelze, Germany) as the P source. After dissolving 0.015 mole (CH3COO)2Ca·xH2O in different deionized water/anhydrous methanol (Merck) volume ratio, Poly (acrylic acid) (Mw 2000) (PAA, Aldrich Chemical company, Inc., USA) was added to the solution and adjusted the solution to the pH value of 9 using 5 M NaOH solution. Phosphoric acid (0.01 mole) was then dropped into the above solution and at the same time, the sodium hydroxide solution was used to keep the solution at pre-determined pH value throughout the entire synthesis process. 因為滴加的濃磷酸是強酸,反應(yīng)過程中ph降得很快,我直接往反應(yīng)體系中加NaOH固體,但還是不好控制,有ph計,但是讀取也有一個過程。想了很久沒有想到很好的方法,希望得到各位達人相助,很感激! |
|
本專業(yè)老本行啊喲西 一個不講道理缺又最合理的辦法 氫氧化鈉溶液濃度足夠。ɡ碛上炔徽f后面你就明白了) 磷酸濃度足夠稀(理由同上) 蠕動泵轉(zhuǎn)子泵隔膜泵任意一種(通過控制轉(zhuǎn)速和氣體體積來控制流速) 同時向目標溶液中添加觀測PH 高了增大磷酸共給泵的流速 低了減小磷酸泵的流速或者增大氫氧化鈉流速 現(xiàn)在知道為什么濃度要低了嗎? 是為了獲得足夠的精度 以上是白富美版 下面來個土肥圓版 虹吸管添加,通過控制管徑和壓力差,(就是高度差) 來獲得合適的流速 樓主你要還不懂就來我家洗尿布 |

至尊木蟲 (著名寫手)
頭腦+肌肉=真男人!

專家顧問 (職業(yè)作家)
![]() |
專家經(jīng)驗: +264 |
銀蟲 (正式寫手)
鐵蟲 (初入文壇)
鐵蟲 (初入文壇)
鐵蟲 (初入文壇)
鐵蟲 (初入文壇)
| 最具人氣熱帖推薦 [查看全部] | 作者 | 回/看 | 最后發(fā)表 | |
|---|---|---|---|---|
|
[考研] 0703 化學 求調(diào)劑,一志愿山東大學 342 分 +5 | Shern—- 2026-03-28 | 5/250 |
|
|---|---|---|---|---|
|
[考研] 材料與化工272求調(diào)劑 +16 | 阿斯蒂芬2004 2026-03-28 | 16/800 |
|
|
[考研] 299求調(diào)劑 +10 | 15188958825 2026-03-25 | 10/500 |
|
|
[考研] 一志愿南昌大學324求調(diào)劑 +5 | hanamiko 2026-03-29 | 5/250 |
|
|
[考研] 298求調(diào)劑 +3 | 種圣賜 2026-03-29 | 3/150 |
|
|
[考研] 356求調(diào)劑 +4 | gysy?s?a 2026-03-28 | 4/200 |
|
|
[考研] 085602 化工專碩 338分 求調(diào)劑 +12 | 路癡小琪 2026-03-27 | 12/600 |
|
|
[考研] 一志愿中南大學化學0703總分337求調(diào)劑 +5 | niko- 2026-03-27 | 5/250 |
|
|
[考研] 070300求調(diào)劑306分 +4 | 26要上岸 2026-03-27 | 4/200 |
|
|
[考研] 283求調(diào)劑 +7 | A child 2026-03-28 | 7/350 |
|
|
[考研] 086502化學工程342求調(diào)劑 +6 | 阿姨復古不過 2026-03-27 | 6/300 |
|
|
[考研] 085701環(huán)境工程求調(diào)劑 +9 | 多久上課 2026-03-27 | 9/450 |
|
|
[考研] 298調(diào)劑 +3 | jiyingjie123 2026-03-27 | 3/150 |
|
|
[考研] 考研調(diào)劑 +10 | 呼呼?~+123456 2026-03-24 | 10/500 |
|
|
[考研] 調(diào)劑推薦 +5 | 清酒714 2026-03-26 | 6/300 |
|
|
[考研]
|
WWW西西弗斯 2026-03-24 | 8/400 |
|
|
[考研] 化學調(diào)劑一志愿上海交通大學336分-本科上海211 +4 | 小魚愛有機 2026-03-25 | 4/200 |
|
|
[考研] 285求調(diào)劑 +3 | AZMK 2026-03-24 | 3/150 |
|
|
[考研]
|
13659058978 2026-03-24 | 4/200 |
|
|
[考研] 344求調(diào)劑 +3 | desto 2026-03-24 | 3/150 |
|