Method for improving yield of humic acid salt prepared from weathered coal

Abstract

The invention provides a method for improving the yield of a humic acid salt prepared from weathered coal. The method includes: under normal temperature and pressure, adding the residue of humic acid extracted weathered coal or lignite into a reaction container, adding a catalyst accounting for 0.01%-10% of the mass of the residue and an oxidant water solution that is 1-30 times the mass of the residue; conducting intense stirring to form a suspension, and adding excess lye according to the pH value of the suspension so as to ensure the pH value of the residue suspension in the range from neutral to alkaline; stopping stirring after reaction for 30min-96h; carrying out centrifugal separation or pumping filtration washing to separate a humic acid salt solution and secondary residue. The treatment method of the secondary residue is basically identical to the above method, and due to inclusion of the catalyst in the secondary residue, adding of the catalyst is no longer needed, thus realizing recycling of the catalyst. At the same time, the yield of the humic acid salt can be increased constantly by cyclic operation. And in the reaction process, the nanoscale catalyst shows good catalytic performance, compared with commercial grade catalysts, the humic acid yield is over 20% higher, and compared with no adding of catalyst, the yield of humic acid is over 30% higher.

Description

technical field [0001] The invention belongs to the field of applied chemistry for converting weathered coal or lignite into humic acid by nano catalysts. Low-grade coal, such as weathered coal and lignite, cannot be used as a heat source or thermal power generation because of its low heat energy and low utilization value. However, low-grade coal contains humic acid, which can be extracted after lye extraction, and the remaining residue still contains high organic matter content. How to efficiently extract organic matter has become an urgent problem. In the invention, the nanometer metal oxide catalyst is added to the residue to efficiently convert it into humic acid, which reduces the discharge of residue and improves the yield of humic acid, and finally achieves the purpose of protecting the environment and improving resource utilization. Background technique [0002] my country is rich in low-grade coal resources such as weathered coal, but in recent decades, low-grade c...

AI Technical Summary

Problems solved by technology

At the same time, in view of the low yield of humate reported in the literature, long reaction time and high reaction energy consumption, the present invention provides a low energy consumption, relatively short and efficient extraction of humic acid method, by adding nano-metal oxide catalysts at normal temperature and pressure, the organic matter in the residue is cracked to the greatest extent and turned into smaller molecules, and the organic matter content in the final residue is less, most of which are inorganic matter, and at the same time Contains metal elements that are beneficial to the soil, thus realizing the recycling of resources and minimizing pollution to the environment

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