CN105195088A - Method for preparing adsorbent for adsorbing trivalent chromium by using diatom zeolite through manganese oxide compound modification - Google Patents

Abstract

The invention discloses a method for preparing an adsorbent for adsorbing trivalent chromium by using diatom zeolite through manganese oxide compound modification. The method comprises the following steps: (1), taking and then adding 10 g of purified diatomite and 3 g of zeolite into 30 mL of a NaOH solution with the concentration of 2-2.2 mol/L, oscillating at a temperature of 90-95 DEG C for 90-100 min, then removing the upper solution; further adding 100 mL of a MnCl2 solution with the concentration of 1-1.1 mol/L, regulating the pH value to be 1-2 by using analytically pure HCl, leaving to stand for 90 min, stirring for 40-50 min, further leaving to stand for 24-48 h, and removing the supernatant liquid; (2), adding 20 mL of a MnCl2 solution with the concentration of 1-1.1 mol/L into the solution obtained in the step (1), stirring, and leaving to stand; (3), adding 20 mL of a MnCl2 solution with the concentration of 1-1.1 mol/L into the solution obtained in the step (2), stirring, leaving to stand, removing the supernatant liquid, cleaning with pure water till to neutral, centrifuging to enable solid and liquid to be separated, taking out solids for drying at a temperature of 105 DEG C, crushing, and sieving with a 200-mesh sieve, so as to obtain the adsorbent. According to the method for preparing the adsorbent capable of adsorbing trivalent chromium by using diatom zeolite through manganese oxide compound modification, provided by the invention, trivalent chromium is recycled from rinsing waste water of electrolytic zinc, and the recovery ratio is increased.

Description

With manganese oxide composite modified diatom zeolite preparation absorption Cr 3+the method of adsorbent

Technical field

The present invention relates to one with diatom zeolite for raw material, manganese oxide composite modified preparation absorption Cr ³⁺the method of adsorbent.

Background technology

Containing Cr ³⁺waste water is mainly derived from the percolate of metallurgy, plating, battery and solid waste landfills.The discharge of wastewater of heavy metal ion, in environment, can only change its form or be transferred, dilutes and accumulate, but can not be degraded, very harmful.Cadmium and a lot of systems of compound to human body thereof have side effect.

Diatomite is a kind of biogenic silicastone, primarily of the placer deposits of Diatomeae remains through silication consolidation.But natural diatomaceous earth adsorption capacity is little, often need to carry out modification to diatomite.Zeolite is the mineral with good adsorption.Research adopt there is the diatom of adsorption capacity, zeolite is raw material, manganese oxide composite modifying method prepares adsorbent, research modification diatom, zeolite heavy metal ion Cr ³⁺absorption and recovery.

Cr is reclaimed from electrolytic zinc poaching wastewater ³⁺, improve the rate of recovery, effectively utilize the mineral resources of China, to the recovery of valuable metal, similar design of new processes and the research of exploitation have very major and immediate significance, and technology, science and industrial economy have many benefits.Also meet current national industrial policy simultaneously.

Summary of the invention

The object of this invention is to provide one with diatom zeolite for raw material, manganese oxide composite modified preparation absorption Cr ³⁺the method of adsorbent.

Concrete steps are:

(1) get 10g diatomite essence soil (purify after), to join 30mL concentration be in the NaOH solution of 2-2.2mol/L to 3g zeolite, vibrate 90-100 minute at 90-95 DEG C of temperature, then removes upper solution; Add the MnCl that 100mL concentration is 1-1.1mol/L again ₂solution, adjusts pH to 1-2 with the pure HCl of analysis, leaves standstill 90 minutes, stir 40-50 minute, then leave standstill 24-48 hour, removing supernatant;

(2) in step (1) gained solution, the MnCl that 20mL concentration is 1-1.1mol/L is added ₂solution, stirs, and leaves standstill.

(3) in step (2) gained solution, the MnCl that 20mL concentration is 1-1.1mol/L is added ₂solution, stirs, and leaves standstill, removes supernatant, with pure water to neutral, centrifugally makes Separation of Solid and Liquid, gets solid and dries at 105 DEG C, pulverized 200 mesh sieve, obtain adsorbent.

(4) be that 250mL tool plug conical flask put into by the adsorbent of step (3) gained of 1g/L by 10mL concentration, to add 100mLpH value be 5.4-6.0 containing Cr ³⁺electrolytic zinc poaching wastewater solution, adsorption time 60-65 minute, adsorption temp 25-30 DEG C, after adding a cover in Clothoid type water-bath constant temperature oscillator with the speed oscillation of 150r/min to adsorption equilibrium.

(5) by step (4) gained solution with 0.45 μm of membrane filtration in 10mL centrifuge tube, measure Cr in filtrate with atomic absorption spectrophotometry ³⁺mass concentration; Cr ³⁺the rate of recovery reach 95-98%.

The present invention reclaims Cr from electrolytic zinc poaching wastewater ³⁺, improve the rate of recovery, effectively make use of the mineral resources of China, to the recovery of valuable metal, technology, science and industrial economy have many benefits.Also meet current national industrial policy simultaneously.

Accompanying drawing explanation

Fig. 1 is embodiment of the present invention diatomite essence soil.

Fig. 2 is embodiment of the present invention zeolite.

Fig. 3 is the composite modified diatom of embodiment of the present invention manganese oxide, zeolite.

Detailed description of the invention

embodiment:

(1) get 10g purify after diatomite essence soil, to join 30mL concentration be in the NaOH solution of 2mol/L to 3g zeolite, vibrate 100 minutes at 90 DEG C of temperature, then remove upper solution; Add the MnCl that 100mL concentration is 1mol/L again ₂solution, adjusts pH to 1.5 with the pure HCl of analysis, leaves standstill 90 minutes, stir 40 minutes, then leave standstill 24 hours, removing supernatant.

(2) in step (1) gained solution, the MnCl that 20mL concentration is 1mol/L is added ₂solution, stirs, and leaves standstill.

(3) in step (2) gained solution, the MnCl that 20mL concentration is 1mol/L is added ₂solution, stirs, and leaves standstill, removes supernatant, with pure water to neutral, centrifugally makes Separation of Solid and Liquid, gets solid and dry at 105 DEG C, pulverized 200 mesh sieve, and prepared adsorbent.

(4) be that 250mL tool plug conical flask put into by the adsorbent of step (3) gained of 1g/L by 10mL concentration, add 100mLpH value be 5.5 containing Cr ³⁺electrolytic zinc poaching wastewater solution, adsorption time 60 minutes, adsorption temp 25 DEG C, after adding a cover in Clothoid type water-bath constant temperature oscillator with the speed oscillation of 150r/min to adsorption equilibrium.

(5) by step (4) gained solution with 0.45 μm of membrane filtration in 10mL centrifuge tube, measure Cr in filtrate with atomic absorption spectrophotometry ³⁺mass concentration; Cr ³⁺the rate of recovery reach 98%.

Claims (1)

1. one kind adsorbs Cr with the composite modified diatom zeolite preparation of manganese oxide ³⁺the method of adsorbent, it is characterized in that concrete steps are:

(1) after getting 10g purification, diatomite essence soil and 3g zeolite join 30mL concentration is in the NaOH solution of 2-2.2mol/L, and vibrate 90-100 minute at 90-95 DEG C of temperature, then removes upper solution; Add the MnCl that 100mL concentration is 1-1.1mol/L again ₂solution, adjusts pH to 1-2 with the pure HCl of analysis, leaves standstill 90 minutes, stir 40-50 minute, then leave standstill 24-48 hour, removing supernatant;

(2) in step (1) gained solution, the MnCl that 20mL concentration is 1-1.1mol/L is added ₂solution, stirs, and leaves standstill;

(3) in step (2) gained solution, the MnCl that 20mL concentration is 1-1.1mol/L is added ₂solution, stirs, and leaves standstill, removes supernatant, with pure water to neutral, centrifugally makes Separation of Solid and Liquid, gets solid and dries at 105 DEG C, pulverized 200 mesh sieve, obtain adsorbent.