Method for preparing modified biochar

Abstract

The invention provides a method for preparing modified biochar. The method comprises the following steps: step 1, preparation of rice husk charcoal: cleaning and drying rice husks, performing heating and pyrolyzing in an air-isolated manner, performing cooling, and performing grinding and sieving; step 2, pretreatment of the rice husk charcoal: soaking the rice husk charcoal in the step 1 with acid, alkali and ethanol respectively in sequence, then washing the rice husk charcoal to be neutral, and drying the rice husk charcoal; step 3, preparation of silane-modified rice husk charcoal: adding the rice husk carbon prepared in the step 2 into modifiers of aminopropyltriethoxysilane, water and absolute ethyl alcohol in proportion, performing stirring and mixing uniformly, performing sealing, and taking out sealed product after reaction; and step 4, washing the silane-based modified rice husk charcoal prepared in the step 3 to be neutral, carrying out vacuum filtration, washing filter residues, performing grinding and sieving to obtain the silane-based modified rice husk charcoal. The rice husk charcoal is modified by adopting aminopropyltriethoxysilane, so that the adsorption capacity and the adsorption stability of the rice husk charcoal to zinc are enhanced, and help is provided for treatment of heavy metal wastewater and resource utilization of the rice husk charcoal.

Description

technical field [0001] The invention belongs to the technical field of remediation of heavy metal pollution, and in particular relates to a preparation method of silyl-modified rice husk charcoal. Background technique [0002] With the development of society and economy, industries such as chemical industry, food industry, pharmaceutical industry, electroplating, electronics and smelting will all be involved in heavy metal pollution. Heavy metals are difficult to be biodegraded, but they can be enriched by biomagnification in the food chain, and finally enter the human body. Heavy metals react with proteins and enzymes in the human body, making them inactive, and may also accumulate in human organs, causing chronic poisoning. Zinc is internationally recognized as the most potentially harmful heavy metal. Excessive zinc intake can lead to poisoning. For example, excessive zinc intake can cause acute zinc poisoning. Plants absorbing excessive zinc will have toxic effects on t...

AI Technical Summary

Problems solved by technology

At present, studies have used trimercaptopropyltrimethoxysilane to modify natural materials with mercapto groups, which can remove Cd 2+ , Pb 2+ and other heavy metal ions, but this modification reagent is relatively expensive, and the modification conditions are limited

[0004] In summary, in the prior art, the adsorption performance of rice husk carbon modified with mercapto groups will decrease in the state of reduction or water immersion, and it is easy to oxidize during storage, which may generate disulfides, which in turn generate harmful substances and cause secondary pollution. Sexual agent cost is higher

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