Chemical waste disposal - ACS Publications - American Chemical

waste disposal has always been too limited and vague to be of practical value to a teacher suddenly faced with responsibility for disposing of inherit...
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edited bv MIRIAM C. NAGE; Avo" High School Avon. CT06001

Chemical Waste Disposal Mirlam C. Nagel Avon High School Avon. CT 06001 Although waste disposal is increasingly a concern to chemists, the subiect, per se. is rarely incorporated in the formal training of Ehemical educators. InstrucGon in chemical waste disposal has always been too limited and vague to be of practical value to a teacher suddenly faced with responsibility for disposing of inherited old chemicals in the stockroom such picric acid or-even worse--the dubious conas tents of unlabeled bottles. The drive, following Sputnik, for academic achievement in science led to enthusiastic, sometimes misguided, efforts by students to do special projects. A considerable supply of chemicals accumulated during the 60's and early 70's in school laboratories when monev for science education was readily available and, a t times, ;pent foolishly. In the spirit of thk times, teachers probably gave little thought to hazards, particularly subtle problems like shelf-life or incompatibles in the stockroom. Over the years, enthusiasm and creativity in the sciences have waned in many schools. Eager students have gone; many of their teachers have also gone. But the old chemicals are still there. Once the decision is made to clean house, the problem of how to dispose of the unwanted chemicals can be a major undertaking. The widespread publicity given to the conseauences of imoroner waste disoosal has radicallv chaneed our attitudes toward getting rid'of unwanted chemiali Most chemical eductors want to do the rieht - thine.- Findina- out how is not always easy. Faced with the problem of disposing of 300 a of very old cyclohexene, a chemical prone to iorm dangerous peroxides,' the science chairman of a small secondary school called the U.S. Environmental Protection Agency (EPA) for advice. The state office could offer no better suggestion than that school systems should get together to solve such problems. It appeared that exposing problems was more important to the agency than finding solutions. At the time they were busy publicizing a well pollution problem related to a defunct local chemical company's on-site dump. The agency did refer the caller to their regional office which was only able to suggest that someone should "go to a rocky area away from the school and throw the bottleas far a s pos"Safely Tips" is planned to be a source of safely Infwmation and practical suggenions to meet he special needs of h i t sdool drmisby teachers. it is also intended lo be a lwvm for teachars to share their experiences and seek solutions to safety-relatedproblems. Potential papers should be sent to the column Editw. Mldam C. Nagel did her undergeduate work at MIT and Boston University, receiv-

Ing a BS in Chemical Education from lh4 laner in 1962. She received her MS from Simmons, and a CAGS from University of

Hartford. Ms. Nagel began teachlng in Massachusens where she was also a member of the NE Section ACS Chemical SafetyCommittee. Since 1972 in addition to teaching chemioby. Mrrlam has been involved in devslqoing innovative cunicula in Connecticut and has oressnted numerous Daoers at slate. national and international meetings. Ako, she is a member of the ACS-NSTA Examinations Subcomminee.

sible!'If that disposal technique was not feasible, the names of two commercial disoosal facilities. both verv. exoensive. . were suggested. T h e local oolice had been heloful in removine other unwanted chemicals a t an earlier time. Exactly how they were disposed of is not known, but rumor has it that the bottles were used for t a g e t practice. When the local police werecalled about the cyclohexene, the oroblem seemed too biz for them, and they ~"ggestedthe staie police. Cyclohexene was not on their list of explosively hazardous substances, so the state police were rel"rtant tn remove it. The school then called the American Chemical Society in Washingt~~n? and were put in touch with the author of that section oi"Safetv in Academic Laboratories." The state police then were convi-d that their services were required. When school was not in session, officers arrived with a bomb carrier to remove the bottle. It is not known how they disposed of it. The local fire department was helpful in removing unwanted chemicals from another school's chemistrv deoartment. Their problem was large because the high schbol dated back to the 1800's. Actually there were some very valuable antique pieces of equipment among the many old worthless chemicals. Somehow, a small hrown bottle on a top shelf escaped the first major cleanup. It wasahout one-fourth t ' t ~ l lof liquid and the stopper was badly encrusted. Only the word "chloride" was legihle on the tattered lahel. The teacher was reluctant tocall the firedepartment again for iust one bottle and decided it should not he too daneerous to dispose of the unknown chloride. A weed-covered sand pile, next to heavy woods about 70 feet from theschool parking lot, seemed a harmless place to pour the liquid. The weather was dear and dw. but the sand was damo. The bottle was placed on its side on idp of the pile, and the s&pper oried off. When the first sourt of liauid hit the moist sand. dense white fumes formed and immediately solidified into spongy mass which blocked the mouth of the bottle. The remaining liquid could be seen churning into fumes inside the bottle. An exolosion seemed imminent, so a metal bucket which had been used to carry the chemical from the stockroom was inverted over the bottle. The tearher hacked away to study the situation, then decided to dislodge the bucket with a long stick, and to try to break the bottle by throwing rocks a t i t &om a safe distance. Pressure building up inside would probably have burst the bottle anyway, because it literally exploded a t aglancing blow from asmall stone. T h e chloride spewed out a dense choking smoke which instantaneouslv withered nearhv foliaee. It is believed the unknown chlorihe was titanium &trachroride. All unfamiliar or unknown chemicals should be treated as if they are hazardous. Information on the hauvds of chemicals ,~ 13 of National can he found in The Merck I n d e ~Volume Fire Codes (NFPA) Manual 49, "Hazardous Chemicals Data."4 and the NIOSHIOSHA "Pocket Guide to Chemical v

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~aboACS Committee on Chemical Safety. "Safety in ~cademic ratcfies." Jan. 1976, p. 48. American Chemical Society. 1155 Sixteenth St.. N.W.. Washington. DC 20036. 2The phone number of ACS Safety Referral Servlce is (202) 872-

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Merck 8 Co.. Inc.. Rahway, NJ 07065. National Fire Protection Association. 470 Atlantic Ave., Boston. MA 02210. DHEW (NIOSH)Publication NO. 78-210. Superintendentof Dgcrc ments. U.S. Government Printing Ofiice. Washington. DC 20402. Volume 58 Number 10 October 1981

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As a service to their customers some waste disposal procedures are described in the Aldrich Catalog Handbook of Organic and Biochemicals6 and the Flinn Chemical Catalog Reference Manual. Both chemical companies wisely preface the information with disclaimers and warnings to the reader to wear appropriate procectiv~safety glasses or face shield, glows, and a laboratory coat. For some problems a gas mask or self-contained breathing apparatus is required. Anyone planning todisposeofchemicals isadvised to check with the local EPA oifice / i r . ~ t to ascertain whether the proposed method of waste dis~osalis acccvtable. I'roredures sum-svd in the catalog may no longer be allowed by the U S . ~ b i r o n mental Protection Agency. Regulations are being revised under the Resource Conservation and Recovery Act of 1976 (RCRA). onceold chemicals are cleaned out, waste disposal problems can be minimized if chemicals are purchased prudently. Future articles in Safety Tips will deal with inventory control and chemical storage in detail. It is appropriate heretosuggest that an accurate inventory should be maintained and renewed before any order for chemials is written. Many public schools often in sarine. order sundies once a vear. , . .. The vractice mav be good business for things like paper stock but is unwise for chemicals. Several chemical companies will delay delivery on

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Journal ot Chemical Education

chemicals. -orders. Such a convenience is valuable for hieh-risk " particularly if storage conditions are not good. Waste can be reduced if the teacher has a record of use in the inventory. A "year's supply" can be more reasonably estimated then, allowing for enrollment fluctuations and curriculum revisions. Reasonable amounts of the right chemicals can be ordered. A rule-of-thumb for the usual stock items is to maintain only a one-year supply of hazardous chemicals and not more than a two-year supply of low-risk chemicals. Teachers are advised to dispose of any chemical which has not been entirely used up in its appropriate one (or two) year supply period. The problem of chemical waste disposal is frightening to school administrators who are already having second thoughts about laboratory chemistry. With declining enrollments, costs of supplies and equipment soaring, and g i v i n g unrest among a liability and tax conscious public, secondary school principals are being led to question even the academic merits of potentially hazardous high school chemistry laboratories.8 Abich Chemical Cumany, . . lnc.. 940 W. St. Paul Ave.. Milwaukee. WI 53233. 'Flinn ScientificInc., P.O. Box 231,910 W. Wllson St.. Batavia. IL 60510.

8Hal~tead,D. A,, J. CWM.E m . , 56. 19 (1979).