How to get sugar from sawdust?

Sugar from sawdust can be obtained by hydrolysis, that is, decomposition with water. This is a very common chemical process. Sawdust and other wood waste contain carbohydrate cellulose. From it in the hydrolysis plants glucose is prepared, which can be used in different ways. Most often it is converted into alcohol, the starting product for many chemical syntheses.

A sugar from sawdust can be obtained by hydrolysis, that is, decomposition with water

So, how to get sugar from sawdust? To do this, let's do the following experiment. In a porcelain cup, fill 2-3 tablespoons of sawdust and moisten them with water. Add some more water and an equal amount of the prepared solution sulfuric acid (1:1), mix the liquid slurry well. Close the lid and put the gas stove in the oven for about an hour, you can slightly less.

Then take out the cup, top up the water and mix. Filter the solution and neutralize the filtrate by adding crushed chalk or lime water to it until the bubbles stop carbon dioxide. The end of neutralization can also be judged by testing the liquid with a litmus test or one of the self-made indicators.

Pour the contents of the cup into a milky bottle, shake the liquid and let stand for several hours. Calcium sulphate, formed when the acid is neutralized, settles on the bottom, and the glucose solution remains on top. Carefully pour it into a clean cup and filter.

The last operation remains - evaporation of water in a water bath. After it, light yellow crystals of glucose remain on the bottom, which are not yet sufficiently clean. This is exactly how glucose is obtained in hydrolysis plants, only, of course, not in porcelain cups...

And we can reproduce another industrial process without any special difficulties: we turn one sugar into two others.

With long storage, homemade jam is often candied. This is because the sugar crystallizes from the syrup. With jam, which is sold in the store, this trouble happens much less often. The fact is that in canning plants, other than sugar beet or cane sugar, C12H22O11, other sugary substances are used, for example invert sugar. What is the inversion of sugar and what it leads to, you will learn from the following experience.

Pour in a tube or a glass 10-20 g of a weak sugar solution and add a few drops of dilute hydrochloric acid. After that, heat the solution in a boiling water bath for ten to fifteen minutes, and then neutralize the acid, preferably magnesium carbonate MgCO3.

When the release of carbon dioxide bubbles ceases, allow the liquid to settle. Just in case, check the indicator to see if the acid is completely neutralized. Drain the stagnant liquid and taste it: it will seem less sweet to you than the original solution.

In the finished solution, almost no sucrose remained, but two new substances appeared, glucose and fructose. This process is called the inversion of sugar, and the resulting mixture is invert sugar.

Inverted sugar is much less than ordinary, prone to crystallization. If you carefully evaporate the water bath its solution, you get a thick syrup that looks a bit like honey. After cooling, it does not crystallize. By the way, beloved honey is three quarters of the same carbohydrates as invert sugar, from glucose and fructose. Artificial honey is also made based on invert sugar.

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