Sulfuric Acid, waste gas washing, copper smelting

Additional physico-chemical information

Administrative data

Endpoint:

other: representative mineralogy

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP study but other quality assurance

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Materials and methods

Principles of method if other than guideline:

Chemistry /elemental analysis was determined using ICP (inductively Coupled Plasma spectroscopy).

GLP compliance:

no

Remarks:

but equivalent Quality Assurance

Test material

Test material information

Constituent 1

Reference substance name:

Sulphuric acid, waste gas cooling and cleaning, copper smelting

IUPAC Name:

Sulphuric acid, waste gas cooling and cleaning, copper smelting

Details on test material:

Sample collection made according to ECI/REACH Copper Consortium Standards Protocols (see IUCLID section 1.4)
Name: Weak Acid (internal: B13)
Sample description: Weak acid, bleeding from SO2 cleaning & washing operations (representative)
Sample code: AC_B13_625875

Results and discussion

Results:

The purpose of the study was to determine important chemical properties of B13, representative weak acid solution, bleeding from SO2 cleaning & washing operations sample as supplied by Reach Copper Consortium.

Any other information on results incl. tables

 

Intermediate B13 Sulphuric acid, waste gas cooling and cleaning, Copper smelting   "Solution obtained from the treatment (scrubbing and cooling) of the SO2containing gasses from copper production processes. The solution can be used to produce gypsum or as a leaching agent, or can be thermally decomposed. It consists mainly of sulphuric acid and copper sulphate, and may contain other non ferrous metalcompounds. Synonyms are weak acid, dilute acid, or bleed."
EC name (or recognized name)	Substance covered	EC number / EINECS No.	CAS No.
Sulphuric acid, waste gas cooling and cleaning, copper smelting **	Weak acid, dilute acid, bleed	924-668-6	Not available

 

The chemical composition of weak acid solution, provided by Reach Copper Consortium was analyzed. The weak acid solution consists mainly of sulfur (66.6g/l) and arsenic (6640mg/l). The complete analysis is given in Table2. The density of weak acid is 1.14 g/cm³.

Table 2 gives the elemental sample analysis. The analysis method is described in the previous chapters 5. The precipitated material, mainly lead sulphate (Figure1), is excluded from the assays.

Table2: Chemical composition of studied weak acid sample.

Sample		09TT03914
H2SO4	g/l	231
S	g/l	66.6
As	mg/l	6440
Si	mg/l	544
Na	mg/l	373
Zn	mg/l	206
Fe	mg/l	60.8
Bi	mg/l	49.3
K	mg/l	21.0
Ca	mg/l	20.8
Mg	mg/l	19.7
Sn	mg/l	16.0
Cu	mg/l	9.1
Al	mg/l	5.1
Pb	mg/l	4.8
Sb	mg/l	3.7
Hg	mg/l	0.3
Mn	mg/l	0.3
Ni	mg/l	0.3
Cr	mg/l	0.2
Co	mg/l	< 0.2
Ag	mg/l	< 0.2
TOC	g/l	<1

Applicant's summary and conclusion

Conclusions:

Study assessed full chemistry of a representative Sulphuric acid bleed from waste gas washing and cooling. The proposed RWC chemistry (distribution pattern for each key element, i.e. % from Total into the various soluble species present in the UVCB) can be used for classification of the UVCB substance (mixture toxicity rules)

Executive summary:

The UVCB substance, which is a complex mixture of metallic salts and sulphuric acid, that decomposes and partially precipitates spontaneously at ambient temperature. The precipitate was characterized as PbSO4 (less than <0,1% from total sample), it was separated and not listed in the chemical assay. The S content measured by ICP was converted into H2SO4 (g/l), in order to assess the sulphuric acid content of the UVCB.

The major constituents of the UVCB are Sulphuric acid (with ca. 20%) and water (ca. 78%). In the representative sample, the main residual constituents were As (0,57%), Si (0,05%), Na (0,03%), iron (0,01%), and Zn (0,02%). The TOC was <0.01% and, the other minor constituents were <0,01% each)

Sample		09TT03914	g/g solution	% w/w
H2SO4	g/l	231	2.03E-01	20.30
S	g/l	66.6	5.85E-02	5.85
Cu	mg/l	9.12	8.01E-06	0.00
As	mg/l	6440	5.66E-03	0.57
Fe	mg/l	60.8	5.34E-05	0.01
Ni	mg/l	0.28	2.46E-07	0.00
Co	mg/l	< 0.2	<DL	<DL
Zn	mg/l	206	1.81E-04	0.02
Bi	mg/l	49.3	4.33E-05	0.00
Sb	mg/l	3.73	3.28E-06	0.00
Hg	mg/l	0.3	2.64E-07	0.00
Sn	mg/l	16	1.41E-05	0.00
Pb	mg/l	4.8	4.22E-06	0.00
Ag	mg/l	< 0.2	<DL	<DL
Cr	mg/l	0.2	1.76E-07	0.00
Mn	mg/l	0.3	2.64E-07	0.00
Si	mg/l	544	4.78E-04	0.05
Na	mg/l	373	3.28E-04	0.03
Al	mg/l	5.08	4.46E-06	0.00
Mg	mg/l	19.7	1.73E-05	0.00
Ca	mg/l	20.8	1.83E-05	0.00
K	mg/l	21	1.85E-05	0.00
TOC	g/l	<1	1.00E-02	1.00
density	kg/l	1.14		26.834
density	g/l	1138		73.166
density	mg/l	1138000		100.000
TOTAL:		74.37	0.065355369	7.54
		g/L	g/g	%

Based on these results the following RWC Distribution pattern is derived (relevant for classification):

Sulphur present as sulphate and Sulphuric acid (reported as H2SO4 : ca. 20%)

Arsenic present as soluble forms (100% from total As)

Other (minor) metal elements: present to 100% from total element as soluble form, each <0.1% and even <0.01%