Difference Between Dehydration by H2SO4 and H3PO4

Thekey differencebetween dehydration by H2SO4 and H3PO4 is thatdehydration by H2SO4 is less safe and facilitates a complex reaction, whereas dehydration by H3PO4 is safer and facilitates a less complex reaction.

Dehydration is basically the removal of H2O. Dehydration ofethanol和其他alcoholscan be done using two different acid catalysts: sulfuric acid (H2SO4) and phosphoric (V) acid (H3PO4). In this process, ethanol is dehydrated to get analkeneproduct.

CONTENTS

1.Overview and Key Difference
2.什么是H2SO4脱水
3.What is Dehydration by H3PO4
4.Side by Side Comparison – Dehydration by H2SO4 vs H3PO4 in Tabular Form
5.概括

H2SO4的脱水是什么？

H2SO4脱水是一种化学过程，可用于使用硫酸作为酸催化剂形成醇的烯烃。Therefore, this reaction includes the formation of an unsaturated compound from a saturated compound. In other words, the reactants of this reaction have only single bonds, whereas the products of this reaction have both single and double bonds.

Sulfuric acid is an acid catalyst for the dehydration of alcohols. In this process, we should use concentrated sulfuric acid. However, using this acid catalyst gives somewhat messy results. It is because sulfuric acid is a very strong oxidizing agent, and it can reduce some of the alcohols to give carbon dioxide gas and reduce itself to produce sulfur dioxide gas. Therefore, both these gases occur as contaminants in the final product and should be removed. In addition, there are some other reactions as well; for example, sulfuric acid reacts with alcohol to give a carbon mass.

In the process of dehydration, the alcohol is heated with sulfuric acid in a concentrated state. Here, an excess amount of sulfuric acid should be used in order to make sure all the alcohols react with the acid. A sodium hydroxide solution can be used to remove the unwanted gases produced in this reaction.

What is Dehydration by H3PO4?

H3PO4脱水是一种化学过程，可用于使用磷（V）酸作为酸催化剂形成醇的烯烃。Therefore, this reaction includes the formation of an unsaturated compound from a saturated compound. In other words, the reactants of this reaction have only single bonds, whereas the products of this reaction have both single and double bonds.

与上述方法相似，该方法还需要酸催化剂的浓度状态。我们还需要使用过量的磷酸（V）酸，以确保所有酒精分子都与酸催化剂反应以给出所需的烯烃。此外，使用磷酸脱水主要用于液态烷烃的产生。该反应比用硫酸脱水的主要优点是，该反应不会给出凌乱的结果，并且相对安全（没有产生有害产物，例如，当使用硫酸作为酸催化剂作为有害产物时，会产生二氧化硫）。

What is the Difference Between Dehydration by H2SO4 and H3PO4?

H2SO4脱水是一种化学过程，可用于使用硫酸作为酸催化剂形成醇的烯烃。H3PO4脱水是一种化学过程，可用于使用磷（V）酸作为酸催化剂形成醇的烯烃。H2SO4和H3PO4脱水之间的关键差异在于，H2SO4脱水不太安全，并且促进了复杂的反应，而H3PO4脱水则更安全，并且促进了较不复杂的反应。

Below infographic tabulates more comparisons to discern the difference between dehydration by H2SO4 and H3PO4.

摘要 - H2SO4与H3PO4的脱水

Dehydration of ethanol and other alcohols can be done using two different acid catalysts; sulfuric acid and phosphoric (V) acid. The key difference between dehydration by H2SO4 and H3PO4 is that dehydration by H2SO4 is less safe and facilitates a complex reaction, whereas dehydration by H3PO4 is safer and facilitates a less complex reaction.

Image Courtesy:

1. “Bogert-Cook Synthesis” By Mephisto spa – Own work (Public Domain) viaCommons Wikimedia
2.“Ethylenetetracarboxylic二酐via acid dehydration” By DMacks (talk) – Own work (Public Domain) viaCommons Wikimedia